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9,900 | Amitriptyline poisoning in a 2-year old. | We describe a case of a 2-year-old boy who ingested 35 mg.kg(-1) of amitriptyline. He developed central nervous system toxicity, as demonstrated by coma and seizures and cardiac toxicity (cardiac arrest) within 1 h of ingestion. The cardiac toxicity was refractory to standard therapy. His cardiac rhythm alternated between ventricular tachycardia and pulseless ventricular tachycardia/ventricular fibrillation for a period of 17 h. Following prolonged cardiopulmonary resuscitation and aggressive supportive management, the patient recovered both cardiovascularly and neurologically. An echocardiogram and MRI brain were subsequently performed and were normal. The patient was discharged 2 weeks later with normal cognitive, behavioral and motor function. We discuss the benefit of prolonged and effective cardiopulmonary resuscitation in the management of this potentially fatal poisoning. |
9,901 | Clinical course of acute myocardial infarction in the hypertensive patient in Eastern Spain: the PRIMVAC registry. | The study's objective was to analyze the acute complications and prognosis of acute myocardial infarction (AMI) in hypertensive patients in Spain.</AbstractText>Complications and early mortality were recorded among the patients with AMI admitted to the coronary care units of the 17 hospitals in the Valencia Community (Spain) between 1995 and 2000.</AbstractText>A total of 12.071 patients were registered, of whom 46% were hypertensive (5.550 cases). Atrial fibrillation was more frequent in the hypertensive group, whereas ventricular fibrillation was more common among normotensive patients. We found higher mortality rates in the hypertensive group (14.4% vs 12.4%; P<.001). However, after multivariate adjustment, hypertension was not independently associated with mortality (odds ratio: .95; P=.46), and remained independently associated with a lower risk of primary ventricular fibrillation (odds ratio: .83; P<.05).</AbstractText>Hypertensive patients do not present comparatively greater mortality during AMI, although primary ventricular fibrillation is less common in such subjects.</AbstractText> |
9,902 | Monomorphic ventricular tachycardia due to Brugada syndrome successfully treated by hydroquinidine therapy in a 3-year-old child. | Mutations in the SCN5A gene can cause Brugada syndrome, a genetically inherited form of idiopathic ventricular fibrillation. We describe the case of a 3-year-old child with a structurally normal heart presenting with monomorphic ventricular tachycardia. Her electrocardiogram suggested a Brugada syndrome and the diagnosis was confirmed by the identification of a Brugada syndrome in her mother and in two other family members. Genetic study led to the identification of a c.2516T-->C SCN5A mutation. The child was treated with quinidine therapy without recurrence of arrhythmic events for a time period of 16 months. |
9,903 | Myocardial revascularization in patients with low ejection fraction < or =35%: effect of pump technique on early morbidity and mortality. | Left ventricular dysfunction is an important predictor of in-hospital mortality. Surgical risk among these patients remains high. The present study is conducted to evaluate the difference in early morbidity and mortality among patients with compromised left ventricular function (LVF) after myocardial revascularization using either off-pump or on-pump coronary artery bypass graft.</AbstractText>Between April 2000 and April 2004, 150 patients with ejection fraction (EF) < or =35% underwent isolated coronary artery bypass grafting. Eighty-four patients underwent conventional bypass (mean EF 30.1%+/- 4.2) and 66 patients had off-pump coronary artery bypass (mean EF 27.5%+/- 5.5). Different variables (preoperative, intraoperative, and postoperative) were evaluated and compared. Determination of operation risk was done using EuroSCORE. Patients who underwent OPCAB were more risky due to a high percentage of associated comorbidities, mean EuroSCORE was 12.96 +/- 13.21 in comparison to 8.47 +/- 10.22 in CCAB.</AbstractText>The mean operative mortality was 8.7%. Patients who underwent OPCAB had a lower operative mortality than CCAB (6.1% vs. 10.7%) inspite of a higher preoperative predicted risk score. Completeness of revascularization was higher among the CCAB group (85.7% vs. 69.7%; p = 0.01). Subsequently, the mean number of grafts was significantly higher among this group (3.4+/-0.7 vs. 2.0 +/-0.9; p < 0.001). On the other hand, morbidity was significantly higher in CCAB (35.7% vs. 19.7%; p = 0.03). However, the incidence of both myocardial infarction and atrial fibrillation was more among OPCAB.</AbstractText>Patients with left ventricular dysfunction are high-risk group. These patients can benefit from myocardial revascularization using either off-pump or conventional CABG, but both are associated with a higher mortality and morbidity than those with normal ventricle. The use of off-pump CABG resulted in better clinical outcome and mortality, but less number of grafts performed than those with conventional CABG especially in patients with lowest EF.</AbstractText> |
9,904 | Intracellular sodium increase and susceptibility to ischaemia in hearts from type 2 diabetic db/db mice. | <AbstractText Label="AIMS/HYPOTHESIS" NlmCategory="OBJECTIVE">An important determinant of sensitivity to ischaemia is altered ion homeostasis, especially disturbances in intracellular Na(+) (Na(i)(+)) handling. As no study has so far investigated this in type 2 diabetes, we examined susceptibility to ischaemia-reperfusion in isolated hearts from diabetic db/db and control db/+ mice and determined whether and to what extent the amount of (Na(i)(+)) increase during a transient period of ischaemia could contribute to functional alterations upon reperfusion.</AbstractText>Isovolumic hearts were exposed to 30-min global ischaemia and then reperfused. (23)Na nuclear magnetic resonance (NMR) spectroscopy was used to monitor[Formula: see text] and (31)P NMR spectroscopy to monitor intracellular pH (pH(i)).</AbstractText>A higher duration of ventricular tachycardia and the degeneration of ventricular tachycardia into ventricular fibrillation were observed upon reperfusion in db/db hearts. The recovery of left ventricular developed pressure was reduced. The increase in[Formula: see text] induced by ischaemia was higher in db/db hearts than in control hearts, and the rate of pH(i) recovery was increased during reperfusion. The inhibition of Na(+)/H(+) exchange by cariporide significantly reduced (Na(i)(+)) gain at the end of ischaemia. This was associated with a lower incidence of ventricular tachycardia in both heart groups, and with an inhibition of the degeneration of ventricular tachycardia into ventricular fibrillation in db/db hearts.</AbstractText><AbstractText Label="CONCLUSIONS/INTERPRETATION" NlmCategory="CONCLUSIONS">These findings strongly support the hypothesis that increased (Na(i)(+)) plays a causative role in the enhanced sensitivity to ischaemia observed in db/db diabetic hearts.</AbstractText> |
9,905 | Association of nocturnal arrhythmias with sleep-disordered breathing: The Sleep Heart Health Study. | Sleep-disordered breathing recurrent intermittent hypoxia and sympathetic nervous system activity surges provide the milieu for cardiac arrhythmia development.</AbstractText>We postulate that the prevalence of nocturnal cardiac arrhythmias is higher among subjects with than without sleep-disordered breathing.</AbstractText>The prevalence of arrhythmias was compared in two samples of participants from the Sleep Heart Health Study frequency-matched on age, sex, race/ethnicity, and body mass index: (1) 228 subjects with sleep-disordered breathing (respiratory disturbance index>or=30) and (2) 338 subjects without sleep-disordered breathing (respiratory disturbance index<5).</AbstractText>Atrial fibrillation, nonsustained ventricular tachycardia, and complex ventricular ectopy (nonsustained ventricular tachycardia or bigeminy or trigeminy or quadrigeminy) were more common in subjects with sleep-disordered breathing compared with those without sleep-disordered breathing: 4.8 versus 0.9% (p=0.003) for atrial fibrillation; 5.3 versus 1.2% (p=0.004) for nonsustained ventricular tachycardia; 25.0 versus 14.5% (p=0.002) for complex ventricular ectopy. Compared with those without sleep-disordered breathing and adjusting for age, sex, body mass index, and prevalent coronary heart disease, individuals with sleep-disordered breathing had four times the odds of atrial fibrillation (odds ratio [OR], 4.02; 95% confidence interval [CI], 1.03-15.74), three times the odds of nonsustained ventricular tachycardia (OR, 3.40; 95% CI, 1.03-11.20), and almost twice the odds of complex ventricular ectopy (OR, 1.74; 95% CI, 1.11-2.74). A significant relation was also observed between sleep-disordered breathing and ventricular ectopic beats/h (p<0.0003) considered as a continuous outcome.</AbstractText>Individuals with severe sleep-disordered breathing have two- to fourfold higher odds of complex arrhythmias than those without sleep-disordered breathing even after adjustment for potential confounders.</AbstractText> |
9,906 | Hemodynamic significance of mitral stenosis: use of a simple, novel index by 2-dimensional echocardiography. | We sought to assess the hemodynamic significance of mitral stenosis (MS) using a new index.</AbstractText>We studied 88 patients with MS. Maximum separation of mitral leaflet tips in diastole in parasternal long-axis and apical 4-chamber views was measured. These two parameters were averaged to yield the mitral leaflet separation index. The index was compared with mitral valve area by planimetry and pressure half-time.</AbstractText>The mitral leaflet separation index was measurable in 76 (86.4%) patients. There was excellent correlation with mitral valve area by planimetry (r = 0.91, P < .001) and pressure half-time (r = 0.86, P < .001) across a wide range of mitral valve areas. Good correlation was found even in atrial fibrillation (r = 0.86 and r = 0.79, respectively). The index could discriminate between hemodynamically significant and insignificant MS (P < .001). An index of 0.81 cm or less predicted severe MS with 92.3% sensitivity and 100% specificity whereas a value of 1.11 cm or more identified mild MS with 85.7% sensitivity and 100% specificity.</AbstractText>The mitral leaflet separation index is an independent and reliable measure of MS severity that is easy to measure.</AbstractText> |
9,907 | Clinical predictors and prognostic significance of electrical storm in patients with implantable cardioverter defibrillators. | Insufficient data exists regarding predictors of electrical storms (ES) and clinical outcome in patients treated with an implantable cardioverter defibrillator (ICD). The purpose of this study was to delineate a subgroup of patients likely to experience ES and to determine the impact of ES on mortality in ICD recipients.</AbstractText>Baseline characteristics of 307 ICD-treated patients were retrospectively analysed. ES was defined as two or more ventricular tachyarrhythmias within 24 h leading to an immediate electrical therapy (antitachycardia pacing and/or shock), separated by a period of sinus rhythm. Clinical characteristics and survival of 123 patients experiencing a total of 294 episodes of ES (median 2 ES/patient, range 1-9), were compared with those of 184 ES-free patients during a median follow-up of 826 days (inter-quartile 1141 days). Median actuarial duration for the first ES occurrence after ICD implant was 1417 days [95% confidence interval (CI) 1061-2363] with a median follow-up of 816 days (7-4642 days) in ES-free patients. Univariate analysis identified older age, depressed left ventricular ejection fraction (LVEF), ventricular tachycardia (VT) as index arrhythmia, chronic renal failure and absence of lipid-lowering drugs as variables significantly associated with an increased risk of ES. Multivariable Cox analysis confirmed an independent predictive value for chronic renal failure [hazard ratio (HR) 1.54, 95% CI 0.95-2.51, P=0.052], VT (HR 2.20, 95% CI 1.44-3.37, P=0.0003), and LVEF (HR 0.98, 95% CI 0.97-0.99, P=0.027). In contrast, diabetics (HR 0.49, 95% CI 0.27-0.90, P=0.022) were less affected by ES. There was no difference in survival between both groups.</AbstractText>ES is frequent but does not increase mortality in ICD's recipients. Patients with severe systolic dysfunction, chronic renal failure and VT as initial arrhythmia are likely to experience ES. Diabetics are less affected by ES.</AbstractText> |
9,908 | Vasopressin improves outcome in out-of-hospital cardiopulmonary resuscitation of ventricular fibrillation and pulseless ventricular tachycardia: a observational cohort study. | An increasing body of evidence from laboratory and clinical studies suggests that vasopressin may represent a promising alternative vasopressor for use during cardiac arrest and resuscitation. Current guidelines for cardiopulmonary resuscitation recommend the use of adrenaline (epinephrine), with vasopressin considered only as a secondary option because of limited clinical data.</AbstractText>The present study was conducted in a prehospital setting and included patients with ventricular fibrillation or pulseless ventricular tachycardia undergoing one of three treatments: group I patients received only adrenaline 1 mg every 3 minutes; group II patients received one intravenous dose of arginine vasopressin (40 IU) after three doses of 1 mg epinephrine; and patients in group III received vasopressin 40 IU as first-line therapy. The cause of cardiac arrest (myocardial infarction or other cause) was established for each patient in hospital.</AbstractText>A total of 109 patients who suffered nontraumatic cardiac arrest were included in the study. The rates of restoration of spontaneous circulation and subsequent hospital admission were higher in vasopressin-treated groups (23/53 [45%] in group I, 19/31 [61%] in group II and 17/27 [63%] in group III). There were also higher 24-hour survival rates among vasopressin-treated patients (P < 0.05), and more vasopressin-treated patients were discharged from hospital (10/51 [20%] in group I, 8/31 [26%] in group II and 7/27 [26%] group III; P = 0.21). Especially in the subgroup of patients with myocardial infarction as the underlying cause of cardiac arrest, the hospital discharge rate was significantly higher in vasopressin-treated patients (P < 0.05). Among patients who were discharged from hospital, we found no significant differences in neurological status between groups.</AbstractText>The greater 24-hour survival rate in vasopressin-treated patients suggests that consideration of combined vasopressin and adrenaline is warranted for the treatment of refractory ventricular fibrillation or pulseless ventricular tachycardia. This is especially the case for those patients with myocardial infarction, for whom vasopressin treatment is also associated with a higher hospital discharge rate.</AbstractText> |
9,909 | The changing incidence of ventricular fibrillation in Milwaukee, Wisconsin (1992-2002). | To investigate the changes in annual incidence and survival of out-of-hospital cardiac-etiology arrests of different initial rhythms, particularly ventricular fibrillation (VF) and ventricular tachycardia (VT), among adults (> 21 years old) in Milwaukee County between 1992 and 2002 and establish correlations with patient and emergency medical services (EMS) system-dependent factors.</AbstractText>The study was a retrospective, observational study of all adult (> 21-year-old) patients with out-of-hospital cardiac-etiology arrests with identifiable rhythm and resuscitation attempted by the Milwaukee County EMS system from 1992 to 2002. Nine thousand one hundred seventy cases were enrolled. Primary outcome measures were changes in annual incidence of initial cardiac arrest rhythm, with a focus on VF/VT. Secondary outcome measures were changes in survival to hospital admission and hospital discharge for VF and VT. Patient and EMS system factors potentially affecting the outcome measures were identified and modeled using multivariate logistic regression.</AbstractText>The incidence of out-of-hospital VF/VT arrests decreased steadily from 37.1 per 100,000 in 1992 to 19.4 per 100,000 in 2002. While the incidences of pulseless electrical activity and overall cardiac arrest remained unchanged, the incidence of asystole during the study period increased from 27.3/100,000 to 44.9/100,000. Multivariate regression analyses revealed that age < 80 years, male gender, white race, previous cardiac surgery, and cardiac history were patient-dependent factors predictive of VF/VT. Witnessed arrest, public location, and shorter response time were EMS system-dependent factors predictive of VF/VT. Based on observed trends, none of these correlated factors could explain the decrease in the incidence of VF/VT arrests. Rates of patient survival to hospital admission and discharge were not significantly changed over time. EMS system factors predictive of survival to admission and discharge were witnessed arrest, public location, and decreased number of defibrillations. Prior cardiac surgery and absence of chronic problems were the only patient factors predictive of survival to hospital admission but were not significantly related to survival to hospital discharge.</AbstractText>The incidence of out-of-hospital cardiac arrests in adult patients with presenting rhythm of VF/VT declined, while an increase in asystole occurred. This was not explained by any patient or EMS system-dependent factor. Rate of survival for VF/VT arrest did not significantly change over time. Survival was primarily influenced by EMS system factors and unrelated to patient-dependent factors.</AbstractText> |
9,910 | Actions of flecainide on susceptibility to phase-2 ventricular arrhythmias during infarct evolution in rat isolated perfused hearts. | The mechanism of flecainide-induced unexpected death remains uncertain. Phase-2 ventricular arrhythmias occur during infarct evolution. We examined whether flecainide (0.74 and 1.48 microM, representing the peak unbound plasma and total blood concentrations, respectively, at 'therapeutic' dosage) has proarrhythmic activity on phase-2 arrhythmia susceptibility during infarct evolution. To achieve this, we used the Langendorff-perfused rat heart preparation (n=8 per group) in which baseline phase-2 arrhythmia susceptibility is low. Left main coronary occlusion evoked phase-1 (acute ischaemia-induced) ventricular arrhythmias including fibrillation (VF) in all hearts. By 90 min, hearts were relatively arrhythmia-free. Randomized and blinded switch of perfusion to flecainide at 90 min caused no increase over baseline in the incidence of VF, tachycardia (VT) or premature beats (VPB) during the following 150 min of ischaemia, or during reperfusion (begun 240 min after the onset of ischaemia). In separate hearts, catecholamines (313 nM norepinephrine and 75 nM epinephrine) were co-perfused with flecainide from 90 min of ischaemia. Catecholamine perfusion increased heart rate, coronary flow and QT interval, and shortened PR interval (all P<0.05), actions that were not altered by flecainide. Catecholamine perfusion caused a weak nonsignificant increase in phase-2 VPB, VT and VF incidence, but there was no proarrhythmic interaction with flecainide. In conclusion, the present findings suggest that the increased risk of death associated with clinical use of flecainide is not due to facilitation of phase-2 ventricular arrhythmias. |
9,911 | The prevalence and prognosis of a Brugada-type electrocardiogram in a population of middle-aged Japanese-American men with follow-up of three decades. | The Brugada syndrome is an inherited arrhythmogenic and nonstructural heart disease associated with an increased risk of sudden cardiac death from ventricular fibrillation. There are conflicting data about its prevalence and prognosis. Particularly, population-based studies are lacking in the United States and other countries.</AbstractText>A total of 8006 Japanese-American men aged 45 to 68 years participated in the initial examination of the Honolulu Heart Program during the period of 1965 through 1968. After excluding prevalent cases with coronary heart disease, 864 electrocardiograms coded as right bundle branch block were reviewed using the specified criteria for Brugada-type electrocardiogram. Baseline characteristics and the prognosis of Brugada-type electrocardiogram were compared with 5983 control subjects who had electrocardiograms coded as normal at the initial examination.</AbstractText>There were 12 typical cases and 11 atypical cases of Brugada-type electrocardiogram at the initial examination (prevalence, 0.15% and 0.14%, respectively). Analysis of baseline characteristics revealed no difference between control cases and either typical or atypical Brugada-type electrocardiogram cases except significantly lower body mass index in subjects with Brugada-type electrocardiogram. During the 30-year follow-up period, none of the subjects died suddenly within 24 hours after the onset of symptoms. Survival analysis revealed no significant difference between case and control groups.</AbstractText>Brugada-type electrocardiograms among middle-aged or elderly Japanese-American men are uncommon and are not associated with increased risk of either sudden death or total mortality.</AbstractText> |
9,912 | Common sodium channel promoter haplotype in asian subjects underlies variability in cardiac conduction. | Reduced cardiac sodium current slows conduction and renders the heart susceptible to ventricular fibrillation. Loss of function mutations in SCN5A, encoding the cardiac sodium channel, are one cause of the Brugada syndrome, associated with slow conduction and a high incidence of ventricular fibrillation, especially in Asians. In this study, we tested the hypothesis that an SCN5A promoter polymorphism common in Asians modulates variability in cardiac conduction.</AbstractText>Resequencing 2.8 kb of SCN5A promoter identified a haplotype variant consisting of 6 polymorphisms in near-complete linkage disequilibrium that occurred at an allele frequency of 22% in Asian subjects and was absent in whites and blacks. Reporter activity of this variant haplotype, designated HapB, in cardiomyocytes was reduced 62% compared with wild-type haplotype (P=0.006). The relationship between SCN5A promoter haplotype and PR and QRS durations, indexes of conduction velocity, was then analyzed in a cohort of 71 Japanese Brugada syndrome subjects without SCN5A mutations and in 102 Japanese control subjects. In both groups, PR and QRS durations were significantly longer in HapB individuals (P< or =0.002) with a gene-dose effect. In addition, up to 28% and 48% of variability in PR and QRS durations, respectively, were attributable to this haplotype. The extent of QRS widening during challenge with sodium channel blockers, known to be arrhythmogenic in Brugada syndrome and other settings, was also genotype dependent (P=0.002).</AbstractText>These data demonstrate that genetically determined variable sodium channel transcription occurs in the human heart and is associated with variable conduction velocity, an important contributor to arrhythmia susceptibility.</AbstractText> |
9,913 | T-wave alternans and the susceptibility to ventricular arrhythmias. | T-wave alternans (TWA) reflects beat-to-beat fluctuations in the electrocardiographic T-wave, and is associated with dispersion of repolarization and the mechanisms for sudden cardiac arrest (SCA). This review examines the bench-to-bedside literature that, over decades, has linked alternans of repolarization in cellular, whole-heart, and human studies with spatial dispersion of repolarization, alternans of cellular action potential, and fluctuations in ionic currents that may lead to ventricular arrhythmias. Collectively, these studies provide a foundation for the clinical use of TWA to reflect susceptibility to ventricular arrhythmias in several disease states. This review then provides a contemporary evidence-based framework for the use of TWA to enhance risk stratification for SCA, identifying populations for whom TWA is best established, those for whom further studies are required, and areas for additional investigation. |
9,914 | Sudden death is less common than might be expected in underprivileged ethnic minorities at high cardiovascular risk. | Sudden cardiac death can be the presenting feature of coronary disease. Limited epidemiological studies from the US suggest an increased prevalence of sudden death in the African-American community. There are no reports in UK minority communities. We present sudden death data from an area with a high density of underprivileged ethnic minority groups.</AbstractText>Ambulance data forms and accident and emergency records of all sudden unexpected deaths bought to City Hospital Birmingham in 2002 were extracted by retrospective review. The clinical characteristics and timing of the events were defined and analysed on the basis of the ethnic origins of the victims.</AbstractText>The prevalence of sudden death amongst Caucasians was substantially greater than among minorities. Both Indo-Asians and Afro-Caribbean groups had a lower than expected sudden death rate. Caucasian patients more commonly demonstrated a ventricular fibrillation (VF) rhythm at presentation while Indo-Asians and Afro-Caribbean's demonstrated a non-VF rhythm (asystole and pulseless electrical activity (PEA). Collapse with syncope was more common in Afro-Caribbean subjects while Indo-Asian subjects more often arrested in transit. There were no differences in call or transfer times.</AbstractText>Despite a well-described pattern of more aggressive coronary disease, particularly noted in South Asian communities in the UK, the sudden death rate are not increased and may be decreased. This implies a potentially separate mechanism or a confounding cultural influence in these events.</AbstractText> |
9,915 | Does atrial fibrillation in very elderly patients with chronic systolic heart failure limit the use of carvedilol? | It is well known that beta-blockers are useful in patients with chronic heart failure (CHF). These favourable effects have recently been observed even in elderly CHF patients. Objectives of the present study were to evaluate the feasibility, tolerability and safety of carvedilol therapy in a cohort of patients > 70 years of age with CHF and left ventricular ejection fraction < 40% with chronic atrial fibrillation. For this purpose, we designed an observational, 12-month prospective study.</AbstractText>Among 240 patients who were referred to our centers and met inclusion criteria, 64 had chronic atrial fibrillation (27%). Thirty-nine out of these 64 subjects (61%) were treated with carvedilol, while 25 patients (39%) had contraindications to such treatment. In the cohort of 176 patients with stable sinus rhythm (control group), carvedilol could be administered in 121 patients (69%), while it was not given in 55 (31%, p=ns). Airways disease was the main reason for exclusion from carvedilol in this setting of patients. No difference in 1-year tolerability of study drug was observed among patients with chronic atrial fibrillation (29 of 33 patients=87.9%) and stable sinus rhythm (95 of 102=93.1%). Adverse events leading to the discontinuation of carvedilol in these two populations were rare and never resulted in any disability, death or were life-threatening.</AbstractText>In over-70 patients with systolic CHF, chronic atrial fibrillation does not limit the possibility of testing beta-blocker therapy. Carvedilol was equally tolerated and safe in patients with atrial fibrillation and sinus rhythm.</AbstractText> |
9,916 | Is there progress in the autopsy diagnosis of sudden unexpected death in adults? | Sudden death is now currently described as natural unexpected death occurring within 1h of new symptoms. Most studies on the subject focused on cardiac causes of death because most of the cases are related to cardiovascular disease, especially coronary artery disease. The incidence of sudden death varies largely as a function of coronary heart disease prevalence and is underestimated. Although cardiac causes are the leading cause of sudden death, the exact incidence of the other causes is not well established because in some countries, many sudden deaths are not autopsied. Many risk factors of sudden cardiac death are identified: age, gender, heredity factors such as malignant mutations, left ventricular hypertrophy and left ventricle function impairment. The role of the police surgeon in the investigation of sudden death is very important. This investigation requires the interrogation of witnesses and of the family members of the deceased. The interrogation of physicians of the rescue team who attempted resuscitation is also useful. Recent symptoms before death and past medical history must be searched. Other sudden deaths in the family must be noted. The distinction between sudden death at rest and during effort is very important because some lethal arrhythmia are triggered by catecholamines during stressful activity. The type of drugs taken by the deceased may indicate a particular disease linked with sudden death. Sudden death in the young always requires systematic forensic autopsy performed by at least one forensic pathologist. According to recent autopsy studies, coronary artery disease is still the major cause of death in people aged more than 35 years. Cardiomyopathies are more frequently encountered in people aged less than 35 years. The most frequent cardiomyopathy revealed by sudden death is now arrhythmogenic right ventricular cardiomyopathy also known simply as right ventricular cardiomyopathy (RVC). The postmortem diagnosis of cardiomyopathies is very important because the family of the deceased will need counseling and the first-degree relatives may undergo a possible screening to prevent other sudden deaths. In each case of sudden death, one important duty of the forensic pathologist is to inform the family of all autopsy results within 1 month after the autopsy. Most of the recent progress in autopsy diagnosis of sudden unexpected death in the adults comes from molecular biology, especially in case of sudden death without significant morphological anomalies. Searching mutations linked with functional cardiac pathology such as long-QT syndrome, Brugada syndrome or idiopathic ventricular fibrillation is now the best way in order to explain such sudden death. Moreover, new syndromes have been described by cardiologists, such as short-QT syndrome and revealed in some cases by a sudden death. Molecular biology is now needed when limits of morphological diagnosis have been reached. |
9,917 | [Effects of tetramethylpyrazine on fibrosis of atrial tissue and atrial fibrillation in a canine model of congestive heart failure induced by ventricular tachypacing]. | To explore the effects of tetramethylpyrazine (TMP) on fibrosis of atrial tissue and atrial fibrillation in a canine model of congestive heart failure (CHF) induced by ventricular tachypacing.</AbstractText>Twenty-one healthy mongrel dogs were randomly divided into three groups, which were normal control group, untreated group and TMP-treated group. Atrial fibrillation (AF) was induced by burst of atrial pacing, after the canine model of CHF was established. The atrial tissues were sampled and stained with Mallory's trichromic stains, then the fibrosis in the atrial tissues was analyzed. The left ventricular ejection fraction (LVEF) was evaluated by echocardiography. The levels of angiotensin II (AngII), aldosterone (ALD), amino-terminal peptide of type III procollagen (PIIINP)ìlaminin (LN) and hyaluronic acid (HA) in peripheral blood were examined by radioimmunoassay.</AbstractText>The LVEF was significantly decreased in the untreated group as compared with that in the normal control group (P<0.01), while the frequencies of AF and sustaining AF were significantly increased and the AF duration was obviously prolonged in the untreated group as compared with those in the normal control group (P<0.01). The fibrosis degree in the left or right atrial tissue in the untreated group was more serious than that in the normal control group (P<0.01). The AF duration was positively correlated with the fibrosis degree in the left atrial tissue (r=0.84, P=0.018). The levels of AngII, ALD, PIIINP and HA in peripheral blood were significantly higher in the untreated group than those in the normal control group (P<0.05 or P<0.01). The level of AngII was positively correlated with the level of ALD in peripheral blood (r=0.759, P=0.048). The LVEF and the frequency of sustaining AF were both significantly improved in the TMP-treated group as compared with those in the untreated group (P<0.05). The fibrosis in the left or right atrial tissue in the untreated group was more serious than that in the untreated group (P<0.01). The levels of AngII and PIIINP in peripheral blood were also markedly higher in the TMP-treated group than those in the untreated group (P=0.05, P=0.01).</AbstractText>Tetramethylpyrazine has the effect of reducing the fibrosis degree of atrial tissue in dogs with CHF, and this efficacy may be related to the mechanism of decreasing the frequency of AF and shortening the AF duration.</AbstractText> |
9,918 | Comparison of beta-blockers, amiodarone plus beta-blockers, or sotalol for prevention of shocks from implantable cardioverter defibrillators: the OPTIC Study: a randomized trial. | Implantable cardioverter defibrillator (ICD) therapy is effective but is associated with high-voltage shocks that are painful.</AbstractText>To determine whether amiodarone plus beta-blocker or sotalol are better than beta-blocker alone for prevention of ICD shocks.</AbstractText><AbstractText Label="DESIGN, SETTING, AND PATIENTS" NlmCategory="METHODS">A randomized controlled trial with blinded adjudication of events of 412 patients from 39 outpatient ICD clinical centers located in Canada, Germany, United States, England, Sweden, and Austria, conducted from January 13, 2001, to September 28, 2004. Patients were eligible if they had received an ICD within 21 days for inducible or spontaneously occurring ventricular tachycardia or fibrillation.</AbstractText>Patients were randomized to treatment for 1 year with amiodarone plus beta-blocker, sotalol alone, or beta-blocker alone.</AbstractText>Primary outcome was ICD shock for any reason.</AbstractText>Shocks occurred in 41 patients (38.5%) assigned to beta-blocker alone, 26 (24.3%) assigned to sotalol, and 12 (10.3%) assigned to amiodarone plus beta-blocker. A reduction in the risk of shock was observed with use of either amiodarone plus beta-blocker or sotalol vs beta-blocker alone (hazard ratio [HR], 0.44; 95% confidence interval [CI], 0.28-0.68; P<.001). Amiodarone plus beta-blocker significantly reduced the risk of shock compared with beta-blocker alone (HR, 0.27; 95% CI, 0.14-0.52; P<.001) and sotalol (HR, 0.43; 95% CI, 0.22-0.85; P = .02). There was a trend for sotalol to reduce shocks compared with beta-blocker alone (HR, 0.61; 95% CI, 0.37-1.01; P = .055). The rates of study drug discontinuation at 1 year were 18.2% for amiodarone, 23.5% for sotalol, and 5.3% for beta-blocker alone. Adverse pulmonary and thyroid events and symptomatic bradycardia were more common among patients randomized to amiodarone.</AbstractText>Despite use of advanced ICD technology and treatment with a beta-blocker, shocks occur commonly in the first year after ICD implant. Amiodarone plus beta-blocker is effective for preventing these shocks and is more effective than sotalol but has an increased risk of drug-related adverse effects.Clinical Trials Registration ClinicalTrials.gov Identifier: NCT00257959.</AbstractText> |
9,919 | Conversion of atriopulmonary Fontan to extracardiac total cavopulmonary connection improves cardiopulmonary function. | Experimental studies showed that extracardiac total cavopulmonary connection provides superior hemodynamics than atriopulmonary Fontan.</AbstractText>We prospectively assessed the impact of conversion of atriopulmonary Fontan to extracardiac total cavopulmonary connection on exercise capacity and cardiac function in 6 consecutive patients.</AbstractText>Six months after conversion to extracardiac total cavopulmonary connection, we observed an increase in peak oxygen uptake in all patients (p=0.01;+17%). This improvement was associated to an increase of peak O(2) pulse (p=0.01;+16%), but no change in peak heart rate, arterial oxygen saturation at peak exercise, and pulmonary function. Ventricular ejection fraction did not change significantly after surgery. Conversion was associated with an improvement in heart failure symptoms as assessed by the New York Heart Association classification. Patients who had undergone additional anti-arrhythmia surgery for atrial fibrillation had no recurrence of arrhythmia at follow-up.</AbstractText>Data indicate that conversion to extracardiac total cavopulmonary connection is associated with an improvement of cardiopulmonary function and heart failure symptoms. Improved exercise capacity is due to an increase in O(2) pulse and may reflect an improved cardiac stroke volume after the operation.</AbstractText> |
9,920 | Integrated electroanatomic mapping with three-dimensional computed tomographic images for real-time guided ablations. | New ablation strategies for atrial fibrillation or nonidiopathic ventricular tachycardia are increasingly based on anatomic consideration and require the placement of ablation lesions at the correct anatomic locations. This study sought to evaluate the accuracy of the first clinically available image integration system for catheter ablation on 3-dimensional (3D) computed tomography (CT) images in real time.</AbstractText>After midline sternotomy, 2.3-mm CT fiducial markers were attached to the epicardial surface of each cardiac chamber in 9 mongrel dogs. Detailed 3D cardiac anatomy was reconstructed from contrast-enhanced, high-resolution CT images and registered to the electroanatomic maps of each cardiac chamber. To assess accuracy, targeted ablations were performed at each of the fiducial markers guided only by the reconstructed 3D images. At autopsy, the position error was 1.9+/-0.9 mm for the right atrium, 2.7+/-1.2 mm for the right ventricle, 1.8+/-1.0 mm for the left atrium, and 2.3+/-1.1 mm for the left ventricle. To evaluate the system's guidance of more complex clinical ablation strategies, ablations of the cavotricuspid isthmus (n=4), fossa ovalis (n=4), and pulmonary veins (n=6) were performed, which resulted in position errors of 1.8+/-1.5, 2.2+/-1.3, and 2.1+/-1.2 mm, respectively. Retrospective analysis revealed that a combination of landmark registration and the target chamber surface registration resulted in <3 mm accuracy in all 4 cardiac chambers.</AbstractText>Image integration with high-resolution 3D CT allows accurate placement of anatomically guided ablation lesions and can facilitate complex ablation strategies. This may provide significant advantages for anatomically based procedures such as ablation of atrial fibrillation and nonidiopathic ventricular tachycardia.</AbstractText> |
9,921 | Calcium instabilities in mammalian cardiomyocyte networks. | The degeneration of a regular heart rhythm into fibrillation (a chaotic or chaos-like sequence) can proceed via several classical routes described by nonlinear dynamics: period-doubling, quasiperiodicity, or intermittency. In this study, we experimentally examine one aspect of cardiac excitation dynamics, the long-term evolution of intracellular calcium signals in cultured cardiomyocyte networks subjected to increasingly faster pacing rates via field stimulation. In this spatially extended system, we observed alternans and higher-order periodicities, extra beats, and skipped beats or blocks. Calcium instabilities evolved nonmonotonically with the prevalence of phase-locking or Wenckebach rhythm, low-frequency magnitude modulations (signature of quasiperiodicity), and switches between patterns with occasional bursts (signature of intermittency), but period-doubling bifurcations were rare. Six ventricular-fibrillation-resembling episodes were pace-induced, for which significantly higher complexity was confirmed by approximate entropy calculations. The progressive destabilization of the heart rhythm by coexistent frequencies, seen in this study, can be related to theoretically predicted competition of control variables (voltage and calcium) at the single-cell level, or to competition of excitation and recovery at the cell network level. Optical maps of the response revealed multiple local spatiotemporal patterns, and the emergence of longer-period global rhythms as a result of wavebreak-induced reentries. |
9,922 | The kinetics of spontaneous calcium oscillations and arrhythmogenesis in the in vivo heart during ischemia/reperfusion. | The correlation between spontaneous calcium oscillations (S-CaOs) and arrhythmogenesis has been investigated in a number of theoretical and experimental in vitro models. There is an obvious lack of studies that directly investigate how the kinetics of S-CaOs correlates with a specific arrhythmia in the in vivo heart.</AbstractText>The purpose of the study is to investigate the correlation between the kinetics of S-CaOs and arrhythmogenesis in the intact heart using an experimental model of ischemia/reperfusion (I/R).</AbstractText>Perfused Langendorff guinea pig (GP) hearts were subjected to global I/R (10-15 minutes/10-15 minutes). The heart was stained with a voltage-sensitive dye (RH237) and loaded with a Ca2+ indicator (Rhod-2 AM). Membrane voltage (Vm) and intracellular calcium transient (Ca(i)T) were simultaneously recorded with an optical mapping system of two 16 x 16 photodiode arrays. S-CaOs were considered to arise from a localized focal site within the mapped surface when these preceded the associated membrane depolarizations by 2-15 ms.</AbstractText>In 135 episodes of ventricular arrhythmias from 28 different GP experiments, 23 were linked to S-CaOs that were considered to arise from or close to the mapped epicardial window. Self-limited or sustained S-CaOs had a cycle length of 130-430 ms and could trigger propagated ventricular depolarizations. Self-limited S-CaOs that followed the basic beat action potential (AP)/Ca(i)T closely resembled phase 3 early afterdepolarizations. Fast S-CaOs could remain confined to a localized site (concealed) or exhibit varying conduction patterns. This could manifest as (1) an isolated premature beat (PB), bigeminal, or trigeminal rhythm; (2) ventricular tachycardia (VT) when a regular 2:1 conduction from the focal site develops; or (3) ventricular fibrillation (VF) when a complex conduction pattern results in wave break and reentrant excitation.</AbstractText>The study examined, for the first time in the intact heart, the correlation between the kinetics of focal S-CaOs during I/R and arrhythmogenesis. S-CaOs may remain concealed or manifest as PBs, VT, or VF. A "benign looking" PB during I/R may represent "the tip of the iceberg" of an underlying potentially serious arrhythmic mechanism.</AbstractText> |
9,923 | Increased risk of paroxysmal atrial fibrillation episodes associated with acute increases in ambient air pollution. | We reported previously that 24-hr moving average ambient air pollution concentrations were positively associated with ventricular arrhythmias detected by implantable cardioverter defibrillators (ICDs). ICDs also detect paroxysmal atrial fibrillation episodes (PAF) that result in rapid ventricular rates. In this same cohort of ICD patients, we assessed the association between ambient air pollution and episodes of PAF.</AbstractText>We performed a case-crossover study.</AbstractText>Patients who lived in the Boston, Massachusetts, metropolitan area and who had ICDs implanted between June 1995 and December 1999 (n=203) were followed until July 2002.</AbstractText><AbstractText Label="EVALUATIONS/MEASUREMENTS" NlmCategory="METHODS">We used conditional logistic regression to explore the association between community air pollution and 91 electrophysiologist-confirmed episodes of PAF among 29 subjects.</AbstractText>We found a statistically significant positive association between episodes of PAF and increased ozone concentration (22 ppb) in the hour before the arrhythmia (odds ratio=2.08; 95% confidence interval=1.22, 3.54; p=0.001). The risk estimate for a longer (24-hr) moving average was smaller, thus suggesting an immediate effect. Positive but not statistically significant risks were associated with fine particles, nitrogen dioxide, and black carbon.</AbstractText>Increased ambient O3 pollution was associated with increased risk of episodes of rapid ventricular response due to PAF, thereby suggesting that community air pollution may be a precipitant of these events.</AbstractText> |
9,924 | First documented rhythm and clinical outcome from in-hospital cardiac arrest among children and adults. | Cardiac arrests in adults are often due to ventricular fibrillation (VF) or pulseless ventricular tachycardia (VT), which are associated with better outcomes than asystole or pulseless electrical activity (PEA). Cardiac arrests in children are typically asystole or PEA.</AbstractText>To test the hypothesis that children have relatively fewer in-hospital cardiac arrests associated with VF or pulseless VT compared with adults and, therefore, worse survival outcomes.</AbstractText><AbstractText Label="DESIGN, SETTING, AND PATIENTS" NlmCategory="METHODS">A prospective observational study from a multicenter registry (National Registry of Cardiopulmonary Resuscitation) of cardiac arrests in 253 US and Canadian hospitals between January 1, 2000, and March 30, 2004. A total of 36,902 adults (> or =18 years) and 880 children (<18 years) with pulseless cardiac arrests requiring chest compressions, defibrillation, or both were assessed. Cardiac arrests occurring in the delivery department, neonatal intensive care unit, and in the out-of-hospital setting were excluded.</AbstractText>Survival to hospital discharge.</AbstractText>The rate of survival to hospital discharge following pulseless cardiac arrest was higher in children than adults (27% [236/880] vs 18% [6485/36,902]; adjusted odds ratio [OR], 2.29; 95% confidence interval [CI], 1.95-2.68). Of these survivors, 65% (154/236) of children and 73% (4737/6485) of adults had good neurological outcome. The prevalence of VF or pulseless VT as the first documented pulseless rhythm was 14% (120/880) in children and 23% (8361/36,902) in adults (OR, 0.54; 95% CI, 0.44-0.65; P<.001). The prevalence of asystole was 40% (350) in children and 35% (13 024) in adults (OR, 1.20; 95% CI, 1.10-1.40; P = .006), whereas the prevalence of PEA was 24% (213) in children and 32% (11,963) in adults (OR, 0.67; 95% CI, 0.57-0.78; P<.001). After adjustment for differences in preexisting conditions, interventions in place at time of arrest, witnessed and/or monitored status, time to defibrillation of VF or pulseless VT, intensive care unit location of arrest, and duration of cardiopulmonary resuscitation, only first documented pulseless arrest rhythm remained significantly associated with differential survival to discharge (24% [135/563] in children vs 11% [2719/24,987] in adults with asystole and PEA; adjusted OR, 2.73; 95% CI, 2.23-3.32).</AbstractText>In this multicenter registry of in-hospital cardiac arrest, the first documented pulseless arrest rhythm was typically asystole or PEA in both children and adults. Because of better survival after asystole and PEA, children had better outcomes than adults despite fewer cardiac arrests due to VF or pulseless VT.</AbstractText> |
9,925 | Reconfirmation algorithms should be the standard of care in automated external defibrillators. | Non-sustained and self-terminating arrhythmias pose a significant challenge during resuscitation. Delivery of a defibrillation shock to a non-shockable rhythm has a poorly understood effect on the heart. The importance of assessing rhythm right up until the delivery of a shock is of increased importance when "blind" shocks are being delivered by automatic defibrillators or minimally trained rescuers. Reconfirmation algorithms are common in current-generation implantable defibrillators but this investigation of current-generation AEDs shows that only 71% of devices presently available have reconfirmation algorithms. A case of spontaneous reversion of a non-sustained arrhythmia is presented. The implications of delivering a defibrillator shock to a non-shockable rhythm are discussed. |
9,926 | Advanced electrophysiologic mapping systems: an evidence-based analysis. | To assess the effectiveness, cost-effectiveness, and demand in Ontario for catheter ablation of complex arrhythmias guided by advanced nonfluoroscopy mapping systems. Particular attention was paid to ablation for atrial fibrillation (AF).</AbstractText>Tachycardia Tachycardia refers to a diverse group of arrhythmias characterized by heart rates that are greater than 100 beats per minute. It results from abnormal firing of electrical impulses from heart tissues or abnormal electrical pathways in the heart because of scars. Tachycardia may be asymptomatic, or it may adversely affect quality of life owing to symptoms such as palpitations, headaches, shortness of breath, weakness, dizziness, and syncope. Atrial fibrillation, the most common sustained arrhythmia, affects about 99,000 people in Ontario. It is associated with higher morbidity and mortality because of increased risk of stroke, embolism, and congestive heart failure. In atrial fibrillation, most of the abnormal arrhythmogenic foci are located inside the pulmonary veins, although the atrium may also be responsible for triggering or perpetuating atrial fibrillation. Ventricular tachycardia, often found in patients with ischemic heart disease and a history of myocardial infarction, is often life-threatening; it accounts for about 50% of sudden deaths. Treatment of Tachycardia The first line of treatment for tachycardia is antiarrhythmic drugs; for atrial fibrillation, anticoagulation drugs are also used to prevent stroke. For patients refractory to or unable to tolerate antiarrhythmic drugs, ablation of the arrhythmogenic heart tissues is the only option. Surgical ablation such as the Cox-Maze procedure is more invasive. Catheter ablation, involving the delivery of energy (most commonly radiofrequency) via a percutaneous catheter system guided by X-ray fluoroscopy, has been used in place of surgical ablation for many patients. However, this conventional approach in catheter ablation has not been found to be effective for the treatment of complex arrhythmias such as chronic atrial fibrillation or ventricular tachycardia. Advanced nonfluoroscopic mapping systems have been developed for guiding the ablation of these complex arrhythmias.</AbstractText>Four nonfluoroscopic advanced mapping systems have been licensed by Health Canada: CARTO EP mapping System (manufactured by Biosense Webster, CA) uses weak magnetic fields and a special mapping/ablation catheter with a magnetic sensor to locate the catheter and reconstruct a 3-dimensional geometry of the heart superimposed with colour-coded electric potential maps to guide ablation. EnSite System (manufactured by Endocardial Solutions Inc., MN) includes a multi-electrode non-contact catheter that conducts simultaneous mapping. A processing unit uses the electrical data to computes more than 3,000 isopotential electrograms that are displayed on a reconstructed 3-dimensional geometry of the heart chamber. The navigational system, EnSite NavX, can be used separately with most mapping catheters. The LocaLisa Intracardiac System (manufactured by Medtronics Inc, MN) is a navigational system that uses an electrical field to locate the mapping catheter. It reconstructs the location of the electrodes on the mapping catheter in 3-dimensional virtual space, thereby enabling an ablation catheter to be directed to the electrode that identifies abnormal electric potential. Polar Constellation Advanced Mapping Catheter System (manufactured by Boston Scientific, MA) is a multielectrode basket catheter with 64 electrodes on 8 splines. Once deployed, each electrode is automatically traced. The information enables a 3-dimensional model of the basket catheter to be computed. Colour-coded activation maps are reconstructed online and displayed on a monitor. By using this catheter, a precise electrical map of the atrium can be obtained in several heartbeats.</AbstractText>A systematic search of Cochrane, MEDLINE and EMBASE was conducted to identify studies that compared ablation guided by any of the advanced systems to fluoroscopy-guided ablation of tachycardia. English-language studies with sample sizes greater than or equal to 20 that were published between 2000 and 2005 were included. Observational studies on safety of advanced mapping systems and fluoroscopy were also included. Outcomes of interest were acute success, defined as termination of arrhythmia immediately following ablation; long-term success, defined as being arrhythmia free at follow-up; total procedure time; fluoroscopy time; radiation dose; number of radiofrequency pulses; complications; cost; and the cost-effectiveness ratio. Quality of the individual studies was assessed using established criteria. Quality of the overall evidence was determined by applying the GRADE evaluation system. (3) Qualitative synthesis of the data was performed. Quantitative analysis using Revman 4.2 was performed when appropriate. Quality of the Studies Thirty-four studies met the inclusion criteria. These comprised 18 studies on CARTO (4 randomized controlled trials [RCTs] and 14 non-RCTs), 3 RCTs on EnSite NavX, 4 studies on LocaLisa Navigational System (1 RCT and 3 non-RCTs), 2 studies on EnSite and CARTO, 1 on Polar Constellation basket catheter, and 7 studies on radiation safety. The quality of the studies ranged from moderate to low. Most of the studies had small sample sizes with selection bias, and there was no blinding of patients or care providers in any of the studies. Duration of follow-up ranged from 6 weeks to 29 months, with most having at least 6 months of follow-up. There was heterogeneity with respect to the approach to ablation, definition of success, and drug management before and after the ablation procedure.</AbstractText>Evidence is based on a small number of small RCTS and non-RCTS with methodological flaws.Advanced nonfluoroscopy mapping/navigation systems provided real time 3-dimensional images with integration of anatomic and electrical potential information that enable better visualization of areas of interest for ablationAdvanced nonfluoroscopy mapping/navigation systems appear to be safe; they consistently shortened the fluoroscopy duration and radiation exposure.Evidence suggests that nonfluoroscopy mapping and navigation systems may be used as adjuncts to rather than replacements for fluoroscopy in guiding the ablation of complex arrhythmias.Most studies showed a nonsignificant trend toward lower overall failure rate for advanced mapping-guided ablation compared with fluoroscopy-guided mapping.Pooled analyses of small RCTs and non-RCTs that compared fluoroscopy- with nonfluoroscopy-guided ablation of atrial fibrillation and atrial flutter showed that advanced nonfluoroscopy mapping and navigational systems:Yielded acute success rates of 69% to 100%, not significantly different from fluoroscopy ablation.Had overall failure rates at 3 months to 19 months of 1% to 40% (median 25%).Resulted in a 10% relative reduction in overall failure rate for advanced mapping guided-ablation compared to fluoroscopy guided ablation for the treatment of atrial fibrillation.Yielded added benefit over fluoroscopy in guiding the ablation of complex arrhythmia. The advanced systems were shown to reduce the arrhythmia burden and the need for antiarrhythmic drugs in patients with complex arrhythmia who had failed fluoroscopy-guided ablationBased on predominantly observational studies, circumferential PV ablation guided by a nonfluoroscopy system was shown to do the following:Result in freedom from atrial fibrillation (with or without antiarrhythmic drug) in 75% to 95% of patients (median 79%). This effect was maintained up to 28 months.Result in freedom from atrial fibrillation without antiarrhythmic drugs in 47% to 95% of patients (median 63%).Improve patient survival at 28 months after the procedure as compared with drug therapy.Require special skills; patient outcomes are operator dependent, and there is a significant learning curve effect.Complication rates of pulmonary vein ablation guided by an advanced mapping/navigation system ranged from 0% to 10% with a median of 6% during a follow-up period of 6 months to 29 months.The complication rate of the study with the longest follow-up was 8%.The most common complications of advanced catheter-guided ablation were stroke, transient ischemic attack, cardiac tamponade, myocardial infarction, atrial flutter, congestive heart failure, and pulmonary vein stenosis. A small number of cases with fatal atrial-esophageal fistula had been reported and were attributed to the high radiofrequency energy used rather than to the advanced mapping systems.</AbstractText>An Ontario-based economic analysis suggests that the cumulative incremental upfront costs of catheter ablation of atrial fibrillation guided by advanced nonfluoroscopy mapping could be recouped in 4.7 years through cost avoidance arising from less need for antiarrhythmic drugs and fewer hospitalization for stroke and heart failure. Expert Opinion Expert consultants to the Medical Advisory Secretariat noted the following: Nonfluoroscopy mapping is not necessary for simple ablation procedures (e.g., typical flutter). However, it is essential in the ablation of complex arrhythmias including these:Symptomatic, drug-refractory atrial fibrillationArrhythmias in people who have had surgery for congenital heart disease (e.g., macro re-entrant tachycardia in people who have had surgery for congenital heart disease).Ventricular tachycardia due to myocardial infarctionAtypical atrial flutterAdvanced mapping systems represent an enabling technology in the ablation of complex arrhythmias. The ablation of these complex cases would not have been feasible or advisable with fluoroscopy-guided ablation and, therefore, comparative studies would not be feasible or ethical in such cases. (ABSTRACT TRUNCATED)</AbstractText> |
9,927 | Improved graft patency rates and mid-term outcome of diabetic patients undergoing total arterial myocardial revascularization. | Diabetes negatively affects the outcome of patients undergoing percutaneous transluminal coronary angioplasty (PTCA) or coronary surgery. However, data are lacking with respect to the impact of arterial revascularization in the diabetic population.</AbstractText>Between 1999 and 2003, 100 of 491 diabetics underwent coronary artery bypass graft surgery (CABG) with total arterial grafting (Group 1, G1); these patients were compared with 100 diabetics undergoing conventional CABG with saphenous veins (Group 2, G2), who were matched for Euroscore and other risk factors such as age, obesity, hypertension, left ventricular ejection fraction (LVEF), previous myocardial infarction and chronic obstructive pulmonary disease (COPD).</AbstractText>Both groups had a similar number of diseased coronary vessels (G1=2.6 vs G2= 2.7) and received a similar degree of myocardial revascularization (grafted vessels: G1=2.2 vs G2=2.4). Early outcome was comparable between the groups in terms of ventilatory support (G1=10.8±6 vs G2=10.4±5 hours), intensive care unit (ICU) stay (G1=24±12 vs G2=25±14 hours) and major post-operative complications such as atrial fibrillation (G1=26% vs G2=28%), peri-operative myocardial infarction (G1=1% vs G2=2%)and prolonged ventilatory support (G1=6% vs G2=5%). Hospital mortality was 2% in G1 and 3% in G2. Angiography was performed at a mean follow-up of 34 months in 65.9% and 71.1% of hospital survivors of G1 and G2 respectively: patients of G1 showed a significantly higher patency rate (G1=96% vs G2=83.6%, p=0.02). Additionally, patients of G1 showed a significantly lower incidence of recurrent myocardial ischemia (G1=7 pts. vs G2=18 pts., p=0.03), late myocardial infarction (G1=2 pts. vs G2=10 pts., p=0.03) and need for coronary reintervention (G1=1 pt. vs G2=12 pts, p=0.004).</AbstractText>Total arterial grafting in diabetic patients significantly improved the benefits of coronary surgery providing at mid term a higher graft patency rate with a lower incidence of cardiac related events.</AbstractText> |
9,928 | Determinants of brain natriuretic peptide levels in patients with lone atrial fibrillation. | Although brain natriuretic peptide (BNP) is increasingly being used for screening and monitoring of congestive heart failure, its utility in patients with lone atrial fibrillation (AF) is unclear.</AbstractText>Plasma BNP levels were measured and comprehensive transthoracic echocardiography was performed in 96 subjects (47: sinus rhythm, 49: AF). Patients with structural heart disease were excluded. Potential determinants of BNP levels were identified by univariate and multivariate analyses. Individuals with AF had higher BNP levels than those with sinus rhythm (150 +/- 114 vs 49 +/- 61 pg/ml, p<0.001) The left atrial (LA) volume index (r=0.63, p<0.001), the pulmonary artery systolic pressure (r=0.45, p=0.006), and the early mitral inflow velocity (E)/mitral annular velocity (E') (r=0.36, p=0.04) were found to be independently correlated with BNP level. The correlations between BNP level and LA volume index (p=0.001) or E/E' (p=0.03) were unaltered when subjects with sinus rhythm were removed from the analysis.</AbstractText>BNP levels significantly correlated with LA volume index and E/E' in patients with lone AF, which indicates that the BNP level may reflect early left ventricular dysfunction and LA enlargement in this patient population.</AbstractText> |
9,929 | Prediction of paroxysmal atrial fibrillation using nonlinear analysis of the R-R interval dynamics before the spontaneous onset of atrial fibrillation. | New methods based on nonlinear theory have been developed to give more insight into complex heart rate (HR) dynamics. This study was designed to test the hypothesis that altered HR dynamics, as analyzed with complexity and fractal measures, may precede the spontaneous onset of paroxysmal atrial fibrillation (PAF). Secondly, the difference in the temporal change of these measurements between the different types of atrial fibrillation (AF) was assessed.</AbstractText>From 105 Holter tapes in which PAF was recorded, 44 PAF (>or=5 min) episodes in 33 patients (22 men, 58 +/- 12 years), preceded by sinus rhythm for more than 1 h, were selected and submitted to time-and frequency-domain HR variability analyses, along with detrended fluctuation analysis, approximate entropy (ApEn) and sample entropy (SampEn). The 60 min before the onset of AF were divided into 6 10-min periods and studied using repeated measures ANOVA. PAF episodes were divided into 3 subgroups: an increased HF component and decreased L/H ratio (vagal type, n=20); increased L/H ratio and decreased HF component (sympathetic type, n=14); and non-related type (n=10). None of the time- or frequency-domain parameters showed any significant change before AF in any type of AF. The alpha(1) showed a tendency to decrease before the onset of AF and the change in alpha(1) was divergent according to the AF type. The ApEn decreased before the onset of AF (1.005+/-0.046, 60-50 min before AF to 0.894+/-0.052, 10-0 min before AF; p=0.032). The SampEn also decreased progressively before the start of AF (1.165 +/- 0.085, 60-50 min before AF to 0.887 +/- 0.077, 10-0 min before AF, p=0.003). The decrease in both the ApEn and SampEn was irrespective of the AF type.</AbstractText>A reduction in the ApEn and SampEn, which reflects the nonlinear complexity of HR variability, is a hallmark of altered HR dynamics preceding the spontaneous onset of AF.</AbstractText> |
9,930 | Prolonged QRS duration and severity of mitral regurgitation are unfavorable prognostic markers of heart failure in patients with nonischemic dilated cardiomyopathy. | The goal of the present study was to identify predictors of event-free survival in nonischemic dilated cardiomyopathy (NIDCM) patients after administration of angiotensin-converting enzyme inhibitors (ACEI)/angiotensin receptor blockers (ARB) and beta-blockers.</AbstractText>The study group comprised 78 consecutive patients with NIDCM between 1997 and 2002. NIDCM was defined as ejection fraction (EF) <0.40 and left ventricular end-diastolic diameter (LVEDD) >55 mm on echocardiography and normal coronary angiography. The mean EF and LVEDD was 26.3 +/- 10.5%, and 62.9 +/- 7.1 mm, respectively. Patients were treated with optimal medical therapy including ACEI/ARBs and/or beta-blockers and followed up for 35.6 +/- 27.8 months. The primary endpoint was either cardiac death or hospitalization because of deterioration of heart failure. Cox's regression analysis was used to establish the association of age, sex, EF, LVEDD, left atrial diameter, cardiac index, pulmonary capillary wedge pressure, QRS duration, severity of mitral regurgitation, body mass index, New York Heart Association class and the presence of atrial fibrillation with these events. During follow-up, 23 patients reached the primary endpoint. In a multivariate analysis, EF (chi-square 5.74, p=0.0166), severity of mitral regurgitation (chi-square 12.31, p=0.0004), and QRS duration (chi-square 11.20, p=0.0008) remained significant predictors.</AbstractText>In NIDCM patients, prolonged QRS duration is a high risk factor for remodeling and unfavorable events. The severity of mitral regurgitation was also a strong risk predictor.</AbstractText> |
9,931 | Can nifekalant hydrochloride be used as a first-line drug for cardiopulmonary arrest (CPA)? : comparative study of out-of-hospital CPA with acidosis and in-hospital CPA without acidosis. | Early defibrillation of ventricular tachycardia and fibrillation (VT/VF) is an urgent and most important method of resuscitation for survival in cardiopulmonary arrest (CPA). We have previously reported that nifekalant (NIF), a specific I(Kr) blocker developed in Japan, is effective for lidocaine (LID) resistant VT/VF in out-of-hospital CPA (OHCPA). However, little is known about the differences in the effect of NIF on OHCPA with acidosis and in-hospital CPA (IHCPA) without acidosis.</AbstractText>The present study enrolled 91 cases of DC shock resistant VT/VF among 892 cases of CPA that occurred between June 2000 and May 2003. NIF was used (0.15-0.3 mg/kg) after LID according to the cardiopulmonary resuscitation (CPR) algorithm of Tokai University. The defibrillation rate was higher in the NIF group for both OHCPA and IHCPA than for LID alone, and the VT/VF rate reduction effect could be maintained even with acidosis. However, sinus bradycardia in OHCPA, and torsades de pointes in IHCPA were occasionally observed. These differences in adverse effects might be related to the amount of epinephrine, serum potassium levels, serum pH, and interaction with LID.</AbstractText>NIF had a favorable defibrillating effect in both CPA groups, and it shows promise of becoming a first-line drug for CPR.</AbstractText> |
9,932 | Out-of-hospital resuscitation in Estonia: a bystander-witnessed sudden cardiac arrest. | To evaluate the results of the first epidemiological study on out-of-hospital resuscitation in Estonia.</AbstractText>A prospective cohort study of 2108 consecutive standardized reports on out-of-hospital resuscitation attempts from 1 January 1999 to 31 December 2002 was conducted according to the Utstein style.</AbstractText>In all, 67.3% (1419/2108) of the cardiac arrests were of presumed cardiac aetiology and 60.2% (854/1419) of them were bystander-witnessed. Of these, the 28% bystander cardiopulmonary resuscitation was initiated, and the first rhythm was recorded as ventricular fibrillation or pulseless ventricular tachycardia in 40% of the cases. In the subgroup of patients with bystander-witnessed cardiac arrest of cardiac origin, 10.7% (91/854) were discharged alive in good cerebral performance categories and 7.7% were alive at the 1-year follow-up. The chances of survival increased if the median response time interval was <6 min, cardiac arrest occurred in a public place, patients received bystander cardiopulmonary resuscitation and had an initial rhythm of ventricular fibrillation or pulseless ventricular tachycardia. The discharge rate was 24% (82/343) in the subgroup of patients who had bystander-witnessed cardiac arrest of cardiac origin and an initial rhythm of ventricular fibrillation or pulseless ventricular tachycardia. In this subgroup, the survival rate was 42.6% (40/94) in Tartu urban area, 16.9% (22/130) in Tallinn urban area and 16.8% (20/119) in other regions of Estonia (mostly urban and suburban areas).</AbstractText>The results demonstrate that despite the progress in the management of out-of-hospital cardiac arrest in Estonia, only one centre (Tartu) achieves a better survival rate. Further improvements are needed to raise the quality of the Estonian emergency medical services system, especially in rural areas.</AbstractText> |
9,933 | Increased prevalence of coronary artery disease, silent myocardial ischemia, complex ventricular arrhythmias, atrial fibrillation, left ventricular hypertrophy, mitral annular calcium, and aortic valve calcium in patients with chronic renal insufficiency. | Cardiovascular morbidity and mortality is high in patients with chronic renal insufficiency. Patients with chronic renal insufficiency have an increased prevalence of coronary artery disease, silent myocardial ischemia, complex ventricular arrhythmias, atrial fibrillation, left ventricular hypertrophy, mitral annular calcium, and aortic valve calcium than patients with normal renal function. These risk factors for cardiovascular morbidity and mortality contribute to the increased incidence of cardiovascular morbidity and mortality seen in patients with chronic renal insufficiency. |
9,934 | Unmasking of Brugada syndrome by an antiarrhythmic drug in a patient with septic shock. | Asymptomatic Brugada syndrome patients often display concealed Brugada-type electrocardiogram patterns that result in under-diagnosis of this syndrome. These patients include individuals of both genders and a wide range of ages. They are as likely as non-Brugada patients to have normal longevity or to suffer from a critical illness. Here we report a case of septic shock in which Brugada-type electrocardiogram patterns were induced by pilsicainide administration for the treatment of atrial fibrillation. This case report suggests that some drugs used in the treatment of septic shock can unmask the Brugada-type electrocardiogram pattern and induce lethal ventricular tachyarrhythmia. |
9,935 | Outcomes of cardiopulmonary resuscitation and predictors of survival in patients undergoing coronary angiography including percutaneous coronary interventions. | We studied the outcome of cardiopulmonary resuscitation (CPR) in patients undergoing coronary angiography (CA) and/or percutaneous coronary interventions (PCI). Of 51,985 CA and PCI patients treated between January 1, 1990, and December 31, 2000, 114 required CPR. Records were reviewed for relationships between patient characteristics and various procedures and short-term survival. Long-term survival was compared with that of a matched cohort of patients who did not have an arrest during catheterization and a matched cohort from the general Minnesota population. Over the 11-year period, the overall incidence of CPR was 21.9 per 10,000 procedures. This rate decreased from 33.9 per 10,000 before 1995 to 13.1 per 10,000 after 1995. Overall survival to hospital discharge after CPR was 56.1%. Survival to discharge was less frequent with a history of congestive heart failure, previous coronary artery bypass graft surgery, hemodynamic instability during the procedure, and with prolonged or emergent catheterizations. Pulseless electrical activity (versus asystole or ventricular fibrillation) indicated very poor short-term survival. Interestingly, short-term survival was not related to the extent of coronary artery disease. Long-term survival of patients who survived cardiac arrest was comparable to that of those who did not have arrest during catheterization. In conclusion, the incidence of periprocedural CPR during diagnostic or interventional coronary procedures decreased after 1995. Patients who received CPR in the cardiac catheterization lab have a remarkably frequent survival to hospital discharge rate. Long-term survival of these patients is only minimally reduced. |
9,936 | Microwave ablation for atrial fibrillation: dose-response curves in the cardioplegia-arrested and beating heart. | Microwave ablation has been used to replace the traditional incisions used in the surgical treatment of atrial fibrillation. However, dose-response curves have not been established in surgically relevant models. The purpose of this study was to develop dose-response curves for the Flex 10 (Guidant, Inc) microwave device in both the acute cardioplegia-arrested heart and on the beating heart.</AbstractText>Twelve domestic pigs (40 to 45 kg) were subjected to microwave ablation in either the arrested (n = 6) or beating heart (n = 6). The cardioplegia-arrested heart was maintained at 10 degrees to 15 degrees C while six atrial endocardial and seven right ventricular epicardial lesions were created in each animal. On the beating heart, six right atrial and seven ventricular epicardial lesions were created. Ablations were performed for 15, 30, 45, 60, 90, 120, and 150 seconds (65 W, 2.45 GHz). The tissue was stained with 2,3,5-triphenyl-tetrazolium chloride, and sectioned at 5-mm intervals. Lesion depth and width were determined from digital micrographs.</AbstractText>Mean atrial wall thickness was 2.8 mm (range, 1 to 8 mm). In the arrested heart, 94% of atrial lesions were transmural at 45 seconds and 100% were transmural at 90 seconds. In the beating heart, only 20% of atrial lesions were transmural despite prolonged ablation times (90 seconds). Ventricular lesion width and depth increased with duration of application, and were similar on the arrested and beating hearts.</AbstractText>Microwave ablation produces linear dose-response curves. Transmural lesions can be reliably produced on the arrested heart, but not consistently on the beating heart.</AbstractText> |
9,937 | Surgery for paroxysmal atrial fibrillation in the setting of mitral valve disease: a role for pulmonary vein isolation? | It is unknown whether pulmonary vein isolation or a complete Cox-Maze procedure is needed to ablate paroxysmal atrial fibrillation in patients with mitral valve disease. Our objective was to assess the impact of different surgical treatments for this arrhythmia in patients undergoing mitral valve surgery.</AbstractText>From July 1993 to January 2004, 152 patients underwent combined surgical treatment of paroxysmal atrial fibrillation and mitral valve disease. Ablation procedures included pulmonary vein isolation alone (n = 31, 20%), pulmonary vein isolation with left atrial connecting lesions (n = 80, 53%), and Cox-Maze (n = 41, 27%). The latter had longer durations of atrial fibrillation than the former (p < 0.0001). Rhythm documented on 1,225 postoperative electrocardiograms was used to estimate prevalence of, and risk factors for, atrial fibrillation across time. Ablation failure was defined as occurrence of atrial fibrillation any time beyond 6 months after operation.</AbstractText>Prevalence of postoperative atrial fibrillation peaked at 22% at 2 weeks and declined to 9% at 1 year. Risk factors included older age (p = 0.09), larger left atrium (p = 0.05), and rheumatic (p = 0.003) and degenerative etiologies (p = 0.03). Freedom from ablation failure was 84% at one year. Ablation procedure did not affect prevalence of atrial fibrillation or incidence of ablation failure.</AbstractText>Pulmonary vein isolation alone may be adequate treatment for patients with paroxysmal atrial fibrillation undergoing mitral valve surgery, particularly when it is of short duration. A randomized trial is necessary to examine this strategy, especially in patients with longer duration of paroxysmal atrial fibrillation.</AbstractText> |
9,938 | [Pharmacotherapy of supraventricular arrhythmias. What comes, what remains, what goes?]. | Supraventricular tachycardias consist of AV-nodal-reentrant-tachycardias, atrioventricular tachycardias with accessory pathways (WPW-syndrome), atrial tachycardias, atrial fibrillation and atrial flutter. Only specific ECG interpretation with an exact arrhythmia classification offers the way to perform modern differential therapy including drug treatment and also interventional therapy modalities. In atrial fibrillation, drug treatment is still first-line therapy: physicians have to make a decision either to follow the rate or rhythm control concept. In case of rhythm control, drug therapy is tailored to the individual patient taking into account the patients symptomatology, left ventricular ejection fraction and nature and degree of an underlying cardiac disease. Drug refractory symptomatic atrial fibrillation patients should be considered for interventional treatment like pulmonary vein ablation. Recurrent typical right atrial flutter, AV-nodal-reentrant-tachycardia and all forms of atrioventricular tachycardias however are indications for catheter ablation; long-term drug treatment will only be performed in rare cases. |
9,939 | Implantable cardioverter defibrillator (ICD) in children. | Implantable cardioverter defibrillators (ICD) proved to be effective in the prevention of sudden cardiac death in adults. In children, the experience of ICD therapy is limited. This retrospective study was undertaken to review our experience with ICD implantation in children with special consideration of psychosocial impact of this therapy.</AbstractText>Sixteen children (f:5, m:11, median age 12.2 years, range 4-15.9 years) received an ICD. Eleven patients had survived sudden cardiac death with documented ventricular fibrillation (VF) and five patients had sustained ventricular tachycardia (VT) with hemodynamic significance. The underlying heart disease was congenital in 5, hypertrophic cardiomyopathy in 2, myocarditis in 2 and primary electrical in 7 patients. All leads were implanted transvenously. Mean follow up was 43.1 months (range 1-105 months). All patients are alive. In 7 patients, a total of 387 sustained VT episodes were detected by the ICD. At follow-up, 10 inappropriate shocks were delivered in four patients. One early and six late lead revisions were done in seven patients. 12/16 (75%) patients had concomitant antiarrhythmic drug therapy. About half of the adolescents showed signs of depression and/or anxiety.</AbstractText>ICD therapy via transvenous access for prevention of sudden cardiac death is feasible and effective even in small children. However, the occurrence of lead complications is significant. Since about half of the adolescents showed signs of depression and/or anxiety, professional psychological surveillance should be considered in these patients.</AbstractText> |
9,940 | Risk factors for arrhythmia and late death in patients with right ventricle to pulmonary artery conduit repair--Japanese multicenter study. | Arrhythmia and late cardiac deaths are thought to be major complications in patients after right ventricle (RV) to pulmonary artery (PA) conduit repair, although the incidence and predictors of these complications remain unknown. The aim of this study was to clarify the incidence and risk factors for arrhythmia and late deaths in patients with the RV to PA conduit repair through a Japanese multicenter study.</AbstractText>Three hundred fifty-one hospital survivors who underwent the RV to PA conduit repair before 1995 were studied.</AbstractText>Survival rate after repair was 92% at 10 years, 88% at 20 and 25 years, respectively. Late death was observed in 30 (8.5%) including 4 patients with sudden death (SD). Higher right ventricular pressure (p = 0.02), larger cardio-thoracic ratio after repair (p = 0.02) and higher incidence of brady- or tachy-arrhythmia and SD (9/30) were associated with late death. Six (1.7%) patients developed ventricular tachycardia or ventricular fibrillation (VT/Vf). There were 22 patients who had 23 new-onset supraventricular tachy-arrhythmia (SVT). Right ventricular hypertension (p = 0.04) was associated with VT/Vf or SD. Male sex (p < 0.01), absence of previously aorto-pulmonary shunt (p < 0.05), older age at repair (p < 0.01) or longer length of follow-up (p < 0.01) were associated with SVT.</AbstractText>Arrhythmia and late sudden death are relatively common late after the RV to PA conduit repair. Our data support recent surgical strategies of earlier primary operation and timely reoperation for progressive right ventricular outflow stenosis that may reduce the incidence of late arrhythmias and SD.</AbstractText> |
9,941 | The short QT syndrome as a paradigm to understand the role of potassium channels in ventricular fibrillation. | The recently discovered hereditary channelopathy, the Short QT Syndrome (SQTS), is an important advance in clinical and molecular cardiology that has opened new doors for investigating the manner in which alterations in excitability and action potential morphology may facilitate the occurrence of ventricular fibrillation. In this brief review we address the molecular and genetic features of SQTS in which specific mutations in one of three different potassium channels involved in cardiac repolarization substantially increase the risk of life-threatening tachyarrhythmias. We then summarize new knowledge on the mechanism of wavebreak, which is the hallmark of reentry initiation, and on the role of potassium channels in the ionic mechanisms underlying cardiac excitation and its frequency dependence. The article argues for a detailed understanding of the ionic mechanisms that promote wavebreaks and stable rotors as an essential tool for successful anti-arrhythmic therapy in SQTS and other diseases leading to sudden cardiac death. |
9,942 | Risk factors of ventricular tachyarrhythmias after coronary artery bypass grafting.<Pagination><StartPage>201</StartPage><EndPage>208</EndPage><MedlinePgn>201-8</MedlinePgn></Pagination><Abstract><AbstractText Label="BACKGROUND" NlmCategory="BACKGROUND">Ventricular arrhythmias are rare and represent the most serious arrhythmic complication after coronary artery bypass grafting (CABG).</AbstractText><AbstractText Label="METHODS" NlmCategory="METHODS">The present retrospective study was conducted for identifying patients at risk of ventricular arrhythmias with ventricular signal averaged ECG, standard deviation of all normal RR intervals (SDNN), angiographic and echocardiographic data. We defined ventricular arrhythmias as sustained ventricular fibrillation and ventricular tachycardia. The study population consisted of 209 consecutive patients with sinus rhythm undergoing CABG. The primary endpoint was the occurrence of VA after CABG. The secondary endpoints were hospital length of stay after CABG and the occurrence of VA after hospital discharge.</AbstractText><AbstractText Label="RESULTS" NlmCategory="RESULTS">During the postoperative follow-up ventricular arrhythmias were observed in 11 patients (5%). Patients with ventricular arrhythmias showed a higher incidence of ventricular late potentials (91 vs. 9% of patients, p<0.0001) than patients without ventricular arrhythmias. In addition patients with ventricular arrhythmias had a lower left ventricular ejection fraction (44.2+/-15.2 vs. 60.1+/-13.1%, p<0.0001) and a SDNN (22.4+/-8.8 vs. 34.4+/-16.1 ms, p<0.02). A stepwise logistic regression analysis of all variables identified the combination of ventricular late potentials, ejection fraction < or = 38% and SDNN < or = 28 ms (odds rate 26.00; 95% CI, 3.44-196.67, p<0.002) as an independent predictor of ventricular arrhythmias.</AbstractText><AbstractText Label="CONCLUSIONS" NlmCategory="CONCLUSIONS">The results of our study suggest that the probability of ventricular arrhythmias could be predicted after CABG by a combination of low left ventricular ejection fraction and a measurement of ventricular signal averaged ECG and standard deviation of all normal RR intervals. Patients who can be identified as having a high risk of ventricular arrhythmias should be observed carefully after surgery.</AbstractText></Abstract><AuthorList CompleteYN="Y"><Author ValidYN="Y"><LastName>Budeus</LastName><ForeName>Marco</ForeName><Initials>M</Initials><AffiliationInfo><Affiliation>Department of Cardiology, West-German Heart Centre, University of Duisburg-Essen, Hufelandstr. 55, D-45122 Essen, Germany. marco.budeus@medizin.uni-essen.de</Affiliation></AffiliationInfo></Author><Author ValidYN="Y"><LastName>Feindt</LastName><ForeName>Peter</ForeName><Initials>P</Initials></Author><Author ValidYN="Y"><LastName>Gams</LastName><ForeName>Emmeran</ForeName><Initials>E</Initials></Author><Author ValidYN="Y"><LastName>Wieneke</LastName><ForeName>Heinrich</ForeName><Initials>H</Initials></Author><Author ValidYN="Y"><LastName>Erbel</LastName><ForeName>Raimund</ForeName><Initials>R</Initials></Author><Author ValidYN="Y"><LastName>Sack</LastName><ForeName>Stefan</ForeName><Initials>S</Initials></Author></AuthorList><Language>eng</Language><PublicationTypeList><PublicationType UI="D016428">Journal Article</PublicationType></PublicationTypeList><ArticleDate DateType="Electronic"><Year>2005</Year><Month>12</Month><Day>05</Day></ArticleDate></Article><MedlineJournalInfo><Country>Netherlands</Country><MedlineTA>Int J Cardiol</MedlineTA><NlmUniqueID>8200291</NlmUniqueID><ISSNLinking>0167-5273</ISSNLinking></MedlineJournalInfo><CitationSubset>IM</CitationSubset><MeshHeadingList><MeshHeading><DescriptorName UI="D000368" MajorTopicYN="N">Aged</DescriptorName></MeshHeading><MeshHeading><DescriptorName UI="D017023" MajorTopicYN="N">Coronary Angiography</DescriptorName></MeshHeading><MeshHeading><DescriptorName UI="D001026" MajorTopicYN="N">Coronary Artery Bypass</DescriptorName><QualifierName UI="Q000009" MajorTopicYN="Y">adverse effects</QualifierName></MeshHeading><MeshHeading><DescriptorName UI="D023921" MajorTopicYN="N">Coronary Stenosis</DescriptorName><QualifierName UI="Q000175" MajorTopicYN="N">diagnosis</QualifierName><QualifierName UI="Q000601" MajorTopicYN="Y">surgery</QualifierName></MeshHeading><MeshHeading><DescriptorName UI="D004452" MajorTopicYN="N">Echocardiography</DescriptorName></MeshHeading><MeshHeading><DescriptorName UI="D015716" MajorTopicYN="N">Electrocardiography, Ambulatory</DescriptorName></MeshHeading><MeshHeading><DescriptorName UI="D005260" MajorTopicYN="N">Female</DescriptorName></MeshHeading><MeshHeading><DescriptorName UI="D005500" MajorTopicYN="N">Follow-Up Studies</DescriptorName></MeshHeading><MeshHeading><DescriptorName UI="D006801" MajorTopicYN="N">Humans</DescriptorName></MeshHeading><MeshHeading><DescriptorName UI="D015994" MajorTopicYN="N">Incidence</DescriptorName></MeshHeading><MeshHeading><DescriptorName UI="D008297" MajorTopicYN="N">Male</DescriptorName></MeshHeading><MeshHeading><DescriptorName UI="D011183" MajorTopicYN="N">Postoperative Complications</DescriptorName></MeshHeading><MeshHeading><DescriptorName UI="D011379" MajorTopicYN="N">Prognosis</DescriptorName></MeshHeading><MeshHeading><DescriptorName UI="D012189" MajorTopicYN="N">Retrospective Studies</DescriptorName></MeshHeading><MeshHeading><DescriptorName UI="D012307" MajorTopicYN="N">Risk Factors</DescriptorName></MeshHeading><MeshHeading><DescriptorName UI="D017180" MajorTopicYN="N">Tachycardia, Ventricular</DescriptorName><QualifierName UI="Q000175" MajorTopicYN="N">diagnosis</QualifierName><QualifierName UI="Q000453" MajorTopicYN="N">epidemiology</QualifierName><QualifierName UI="Q000209" MajorTopicYN="Y">etiology</QualifierName></MeshHeading></MeshHeadingList></MedlineCitation><PubmedData><History><PubMedPubDate PubStatus="received"><Year>2005</Year><Month>7</Month><Day>8</Day></PubMedPubDate><PubMedPubDate PubStatus="revised"><Year>2005</Year><Month>9</Month><Day>22</Day></PubMedPubDate><PubMedPubDate PubStatus="accepted"><Year>2005</Year><Month>11</Month><Day>5</Day></PubMedPubDate><PubMedPubDate PubStatus="pubmed"><Year>2005</Year><Month>12</Month><Day>7</Day><Hour>9</Hour><Minute>0</Minute></PubMedPubDate><PubMedPubDate PubStatus="medline"><Year>2006</Year><Month>12</Month><Day>15</Day><Hour>9</Hour><Minute>0</Minute></PubMedPubDate><PubMedPubDate PubStatus="entrez"><Year>2005</Year><Month>12</Month><Day>7</Day><Hour>9</Hour><Minute>0</Minute></PubMedPubDate></History><PublicationStatus>ppublish</PublicationStatus><ArticleIdList><ArticleId IdType="pubmed">16330114</ArticleId><ArticleId IdType="doi">10.1016/j.ijcard.2005.11.014</ArticleId><ArticleId IdType="pii">S0167-5273(05)01343-4</ArticleId></ArticleIdList></PubmedData></PubmedArticle><PubmedArticle><MedlineCitation Status="MEDLINE" Owner="NLM"><PMID Version="1">16329654</PMID><DateCompleted><Year>2006</Year><Month>02</Month><Day>03</Day></DateCompleted><DateRevised><Year>2019</Year><Month>11</Month><Day>09</Day></DateRevised><Article PubModel="Print"><Journal><ISSN IssnType="Print">0947-6075</ISSN><JournalIssue CitedMedium="Print"><Issue>55</Issue><PubDate><Year>2006</Year></PubDate></JournalIssue><Title>Ernst Schering Research Foundation workshop</Title><ISOAbbreviation>Ernst Schering Res Found Workshop</ISOAbbreviation></Journal>Overview on chronic viral cardiomyopathy/chronic myocarditis. | Myocarditis is most often induced by cardiotropic viruses and often resolves with minimal cardiac remodelling and without discernable prognostic impact. Acute myocarditis has a highly diverse clinical presentation (asymptomatic, infarct-like presentation, atrioventricular (AV)-block, atrial fibrillation, sudden death due to ventricular tachycardia, fulminant myocarditis with severely depressed contractility). Progression of myocarditis to its sequela, dilated cardiomyopathy (DCM), has been documented in 20% of cases and is pathogenically linked to chronic inflammation and viral persistence. Persistence of cardiotropic viruses (enterovirus, adenovirus) constitutes one of the predominant aetiological factors in DCM. Additionally, circulating autoantibodies to distinct cardiac autoantigens have been described in patients with DCM, providing evidence for autoimmune involvement. Since clinical complaints of myocarditis and DCM are unspecific, a positive effect of any specific therapy depends on an accurate biopsy-based diagnosis and characterization of the patients with histological, immunohistological and molecular biological methods (PCR), which have developed into sensitive tools for the detection of different viruses, active viral replication, and myocardial inflammation. The immunohistochemical characterization of infiltrates has supported a new era in the diagnosis of myocardial inflammation compared with the Dallas criteria, which has led to a new entity of secondary cardiomyopathies acknowledged by the WHO, the inflammatory cardiomyopathies (DCMi). Immunohistochemically quantified lymphocytes significantly better reflect troponin levels and correlate with findings by anti-myosin scintigraphy compared with the histological analysis. Furthermore, the orchestrated induction of endothelial cell adhesion molecules (CAMs) in 65% of DCM patients has confirmed that CAM induction is a prerequisite for lymphocytic infiltration in DCMi. The combination of these immunohistological with molecular biological diagnostic techniques of virus analysis allows a further classification of dilated cardiomyopathy by differentiating the disease entity in subgroups of virus-positive and virus-negative patients with or without cardiac inflammation. Further analysis of the predominant Th1-/Th2-immune response may provide additional prognostic information on the natural course of the disease. This differential analysis improves the clinical management of patients and is an indispensable prerequisite for the development of specific antiviral or immunomodulatory treatment strategies. |
9,943 | Cardiac video analysis using Hodge-Helmholtz field decomposition. | The critical points (also known as phase singularities) in the heart reflect the pathological change of the heart tissue, and hence can be used to describe and analyze the dynamics of the cardiac electrical activity. As a result, the detection of these critical points can lead to correct understanding and effective therapy of the tachycardia. In this paper, we propose a novel approach to address this problem. The proposed approach includes four stages: image smoothing, motion estimation, motion decomposition, and detection of the critical points. In the image smoothing stage, the noisy cardiac optical data are smoothed using anisotropic diffusion equation. The conduction velocity fields of the cardiac electrical patterns can then be estimated from two consecutive smoothed images. Using the recently developed discrete Hodge-Helmholtz motion decomposition technique, the curl-free and divergence-free potential surfaces of an estimated velocity field are extracted. Finally, hierarchically searching the minima and maxima on the potential surfaces, the sources, sinks, and rotational centers are located with high accuracy. Experimental results with four real cardiac videos show that the proposed approach performs satisfactorily, especially for the cardiac electrical patterns with simple propagations. |
9,944 | Low-K+ dependent QT prolongation and risk for ventricular arrhythmia in anorexia nervosa. | QT prolongation and ventricular arrhythmia have been proposed as the mechanism for sudden death in anorexia nervosa. The prevalence and the cause of QT prolongation remain controversial.</AbstractText>1) to evaluate ventricular repolarization in patients with anorexia; 2) to evaluate factors that may influence repolarization, with focus on electrolyte plasma levels and heart rate.</AbstractText>29 patients with anorexia, age 22 +/- 5 years, BMI 13.8 +/- 1.5 were compared to 14 control female subjects, age 23 +/- 2 years, BMI 20.7 +/- 1.1. QT interval and QT dispersion were measured. Whenever a low potassium (<3.5 mEq/l) was found, ECG was repeated after normalization of serum levels. Heart rate and its variability in the frequency domain (LF/HF ratio) were evaluated.</AbstractText>Three patients (10.3%) showed severe hypokalemia (K(+) levels <2.0 mEq/l). In 2 patients, QT was severely prolonged (QT(c) 600 and 670 msec) and in one case associated with ventricular arrhythmia. QT(c) after K(+) plasma levels normalization was 392 +/- 25 in anorexia vs. 407 +/- 19 msec in controls, p = 0.08. Heart rate was 55 +/- 11 in anorexia vs. 66 +/- 8 beats per minute (BPM) in controls, p = 0.002. The LF/HF ratio was 1.79 +/- 1.35 in anorexia and 3.66 +/- 2.64 in controls, p = 0.006.</AbstractText>QT interval is usually normal in patients with anorexia. QT prolongation and ventricular arrhythmia may develop in the setting of severe hypokalemia, exposing patients to high risk of sudden cardiac event. Resting heart rate is lower in anorexia than in controls with the spectral indices of sympatho-vagal balance indicating a prevalence of vagal activity.</AbstractText> |
9,945 | Frequency of atrial fibrillation and factors related to its development in dialysis patients. | The frequency of atrial fibrillation is increased in patients with end-stage renal disease. In this study, we sought to determine the incidence of persistent and paroxysmal atrial fibrillation in patients with end-stage renal disease and to identify the risk factors associated with this arrhythmia.</AbstractText>Two hundred seventy-five patients with end-stage renal disease who were in a hemodialysis program for at least 4 months were included in the study. Patients with permanent, persistent, or paroxysmal atrial fibrillation were identified and recorded. All patients were evaluated for cardiac risk factors and arrhythmias.</AbstractText>Thirty (10.9%) of the 275 patients were found to have atrial fibrillation. Ten (33.3%) of these patients had permanent or persistent atrial fibrillation, and 20 (66.6%) of these patients had paroxysmal atrial fibrillation. Patients with atrial fibrillation were older. Incidences of hypertension, coronary artery disease, left ventricular systolic dysfunction, right atrial diameters, and mitral and/or aortic calcification were significantly higher in patients with atrial fibrillation. Serum albumin and high-density lipoprotein levels were significantly lower in patients with atrial fibrillation.</AbstractText>Our data indicate that atrial fibrillation is a frequent arrhythmia in patients with end-stage renal disease, and the most frequently encountered form is paroxysmal atrial fibrillation. In this patient group, presence of coronary artery disease, age, and right atrial diameter are independent factors for determination of the risk of development of atrial fibrillation.</AbstractText> |
9,946 | Sleep disorders in systolic heart failure: a prospective study of 100 male patients. The final report. | Heart failure is a highly prevalent disorder. The main aims of this study were to determine the prevalence, consequences and markers of sleep apnea and the periodic limb movements (PLMS) in heart failure.</AbstractText>This is a prospective study of 100 of 114 consecutive eligible patients with heart failure and LVEF <45%. Forty-nine percent of patients had sleep apnea with an average index of 49 per hour. Thirty-seven percent of patients had CSA and 12% had OSA. Comparing patients with CSA to those without sleep apnea, the markers associated with CSA were poorer functional classification, atrial fibrillation, PaCO2 <36 mm Hg, LVEF <20%, and nocturnal ventricular arrhythmias including >30 PVC's, >1 couplets and >1 episodes of ventricular tachycardia/hour. In contrast, comparing heart failure patients with CSA to OSA, OSA patients were significantly obese (mean body weight 109+/-27 vs 78+/-18 kg) and had habitual snoring (83% vs 38%). Twenty percent of patient with heart failure had PLMS with an average index of 35 per hour. PLMS resulted in a mildly increased number of arousals (3.4+/-2 per hour).</AbstractText>49% of male patients with systolic heart failure suffer from sleep apnea and 20% have PLMS. CSA occurs in about 37%, and OSA in 12% of patients. Habitual snoring and obesity are the hallmarks of OSA. In contrast, heart failure patients with CSA are commonly thin and mostly do not snore. Hallmarks of CSA are Class III New York Heart, artrial fibrillation, frequent nocturnal ventricular arrhythmias, low arterial PCO2 and LVEF <20%.</AbstractText> |
9,947 | [Mitral regurgitation]. | Mitral regurgitation is the second most frequent reason for valve surgery. The most important causes of mitral regurgitation are degenerative valve disease (mitral valve prolapse), left ventricular impairment and dilatation (in coronary artery disease or dilated cardiomyopathy), and infective endocarditis. The regurgitation of blood from the left ventricle into the left atrium leads to dilatation of the left atrium, increase in pulmonary capillary pressure and pulmonary congestion. In chronic severe mitral regurgitation, the left ventricle dilates and becomes impaired over time. Key symptoms are fatigue and dyspnea on exertion. The most prominent physical sign is the characteristic systolic murmur. Echocardiography identifies severity, delineates morphology, and estimates the impact of mitral regurgitation on left ventricular function. Importantly, echocardiography identifies candidates for mitral valve repair. Symptomatic patients and asymptomatic patients with impaired left ventricular function should be operated. If possible, valve repair is preferred over valve replacement to better preserve left ventricular function and to avoid the need for postoperative anticoagulation (except if atrial fibrillation persists). |
9,948 | Normoxic resuscitation after cardiac arrest protects against hippocampal oxidative stress, metabolic dysfunction, and neuronal death. | Resuscitation and prolonged ventilation using 100% oxygen after cardiac arrest is standard clinical practice despite evidence from animal models indicating that neurologic outcome is improved using normoxic compared with hyperoxic resuscitation. This study tested the hypothesis that normoxic ventilation during the first hour after cardiac arrest in dogs protects against prelethal oxidative stress to proteins, loss of the critical metabolic enzyme pyruvate dehydrogenase complex (PDHC), and minimizes subsequent neuronal death in the hippocampus. Anesthetized beagles underwent 10 mins ventricular fibrillation cardiac arrest, followed by defibrillation and ventilation with either 21% or 100% O2. At 1 h after resuscitation, the ventilator was adjusted to maintain normal blood gas levels in both groups. Brains were perfusion-fixed at 2 h reperfusion and used for immunohistochemical measurements of hippocampal nitrotyrosine, a product of protein oxidation, and the E1alpha subunit of PDHC. In hyperoxic dogs, PDHC immunostaining diminished by approximately 90% compared with sham-operated dogs, while staining in normoxic animals was not significantly different from nonischemic dogs. Protein nitration in the hippocampal neurons of hyperoxic animals was 2-3 times greater than either sham-operated or normoxic resuscitated animals at 2 h reperfusion. Stereologic quantification of neuronal death at 24 h reperfusion showed a 40% reduction using normoxic compared with hyperoxic resuscitation. These results indicate that postischemic hyperoxic ventilation promotes oxidative stress that exacerbates prelethal loss of pyruvate dehydrogenase and delayed hippocampal neuronal cell death. Moreover, these findings indicate the need for clinical trials comparing the effects of different ventilatory oxygen levels on neurologic outcome after cardiac arrest. |
9,949 | Bayesian evidence synthesis to extrapolate survival estimates in cost-effectiveness studies. | This paper is concerned with survival extrapolation that represents an integral part of cost-effectiveness analysis. In the absence of long-term survival estimates from randomized clinical trials or meta-analysis we show how age-sex matched U.K. population data can additionally be used to estimate survival patterns. We adopt a Bayesian approach and we synthesize evidence from different sources such as patient registries, U.K. population statistics and meta-analyses. We also present methodology for Bayesian analysis of the additive hazards model and we show how to apply the techniques using freely available software. The methods are illustrated using data from a cohort of cardiac arrhythmia patients. |
9,950 | A fuzzy clustering neural network architecture for classification of ECG arrhythmias. | Accurate and computationally efficient means of classifying electrocardiography (ECG) arrhythmias has been the subject of considerable research effort in recent years. This study presents a comparative study of the classification accuracy of ECG signals using a well-known neural network architecture named multi-layered perceptron (MLP) with backpropagation training algorithm, and a new fuzzy clustering NN architecture (FCNN) for early diagnosis. The ECG signals are taken from MIT-BIH ECG database, which are used to classify 10 different arrhythmias for training. These are normal sinus rhythm, sinus bradycardia, ventricular tachycardia, sinus arrhythmia, atrial premature contraction, paced beat, right bundle branch block, left bundle branch block, atrial fibrillation and atrial flutter. For testing, the proposed structures were trained by backpropagation algorithm. Both of them tested using experimental ECG records of 92 patients (40 male and 52 female, average age is 39.75 +/- 19.06). The test results suggest that a new proposed FCNN architecture can generalize better than ordinary MLP architecture and also learn better and faster. The advantage of proposed structure is a result of decreasing the number of segments by grouping similar segments in training data with fuzzy c-means clustering. |
9,951 | Surgical Treatment of Posterior Mitral Valve Prolapse: Towards 100% Repair. | The study aim was to evaluate the immediate and long-term results of surgical treatment of isolated posterior mitral valve leaflet prolapse (PLP), focusing on survival and freedom from recurrent mitral regurgitation (MR).</AbstractText>Between January 1998 and December 2012, a total of 492 consecutive patients (375 males, 117 females; mean age 61.8 ± 12.1 years; range: 13-86 years) with isolated PLP [304 (61.8%) with myxomatous degeneration; 188 (38.2%) with fibroelastic deficiency] were treated at the authors' institution. Of these patients, 202 (41.1%) were in NYHA class III-IV, and atrial fibrillation was present in 104 (21.1%). Mitral valve repair was achieved in 484 patients (98.4%), resection was performed in 419 (85.2%), and prosthetic ring annuloplasty was used in 436 (88.6%). Concomitant procedures were performed in 153 patients (31.1%), including tricuspid valve repair in 50 (10.2%), aortic valve surgery in 34 (6.9%), and coronary artery bypass grafting (CABG) in 64 (13%).</AbstractText>The hospital mortality rate was 0.2%, and the mean follow up was 7.1 ± 3.9 years. There were 71 late deaths (14.4%), and overall survival at five, 10 and 15 years was 91.7 ± 1.3%, 82.1 ± 2.3% and 64.7 ± 6.1%, respectively. There was no significant difference in long-term survival compared with the age- and gender-matched general population (p = 0.146). Multivariate Cox-proportional hazard analysis showed older age (HR 1.03 per annum), left ventricular dysfunction (HR 2.44), atrial fibrillation (HR 1.96), left ventricular end-diastolic dimension (HR 1.05 per mm) and non-use of prosthetic ring (HR 3.03) as significant predictors of late mortality. Recurrence of moderate or severe MR occurred in 31 patients, six of whom underwent mitral valve reoperation. Predictors of late recurrence of MR were fibroelastic deficiency (HR 2.38), mitral calcification (HR 5.26), posterior leaflet plication (HR 3.58), absence of complete ring annuloplasty (HR 3.84) and systolic pulmonary artery pressure at discharge (HR 1.10 per mmHg). Freedom from mitral valve reoperation at 15 years was 97.4 ± 1.1% CONCLUSIONS: Mitral valve repair in isolated PLP can be achieved in virtually all cases with a very low operative risk and a high durability of repair. Atrial fibrillation or large left ventricles are associated with a poor prognosis. Failure to use a complete ring annuloplasty carries a risk not only for the return of MR but also for survival.</AbstractText> |
9,952 | Atrial Fibrillation in Cardiac Sarcoidosis. | Sarcoidosis is a systemic granulomatous disease that affects the myocardium. Although ventricular arrhythmias are well known manifestations of cardiac involvement, there is increasing evidence that a significant proportion of patients with cardiac sarcoidosis (CS) also have atrial arrhythmias, atrial fibrillation being the most frequent. The incidence and mechanism of atrial fibrillation in CS is not precisely known. The management of atrial fibrillation in patients with CS is currently done according to the general guidelines for management of atrial fibrillation. Evidence is emerging regarding the additional role of immunosuppression for the treatment of atrial arrhythmias in CS. This paper reviews the incidence, possible mechanisms and treatment strategies of atrial fibrillation in patients with CS. |
9,953 | Electrical Storm: Incidence, Prognosis and Therapy. | The term "electrical storm" indicates a life-threatening clinical condition characterized by the recurrence of hemodynamically unstable ventricular tachycardia and/or ventricular fibrillation, in particular in patients with ICD implanted for primary or secondary prevention. Although there isn't a shared definition of electrical storm, nowadays the most accepted definition refers to three or more separate arrhythmia episodes leading to ICD therapies including antitachycardia pacing or shock occurring over a single 24 hours' time period. Clinical presentation can be dramatic and triggering mechanism are not clear at all yet, but electrical storm is associated with high mortality rates and low patients quality of life, both in the acute phase and in the long term. The first line therapy is based on antiarrhythmic drugs to suppress electrical storm, but in refractory patients, interventions such as catheter ablation or in some cases surgical cardiac sympathetic denervation might be helpful. Anyhow, earlier interventional management can lead to better outcomes than persisting with antiarrhythmic pharmacologic therapy and, when available, an early interventional approach should be preferred. |
9,954 | Proarrhythmic Effects Of Antiarrhythmic Drugs: Case Study Of Flecainide Induced Ventricular Arrhythmias During Treatment Of Atrial Fibrillation. | Flecainide is a class 1C antiarrhythmic drug especially used for the management of supraventricular arrhythmia. Flecainide also has a recognized proarrhythmic effect in patients treated for ventricular tachycardia. It is used to treat a variety of cardiac arrhythmias including paroxysmal atrial fibrillation, paroxysmal supraventricular tachycardia and ventricular tachycardia. Flecainide has local anesthetic effects and belongs to the class 1C AADs that block sodium channels, thereby slowing conduction through the heart. It selectively increases anterograde and retrograde accessory pathway refractoriness. The action of flecainide in the heart prolongs the PR interval and widens the QRS complex. The proarrhythmic effects however noted are not widely reported.</AbstractText>We report a case of paroxysmal atrial fibrillation with structurally normal heart who was treated with oral Flecainide. There were no adverse events and no QTc prolongation was noted on ECG. Despite subjective improvement a repeat Holter detected him to have multiple short non sustained ventricular arrhythmias.</AbstractText>Development of ventricular arrhythmias, salvos and non-sustained ventricular tachycardia after a month of initiation of oral flecainide detected by 24 hours ECG Holter lead to discontinuation of flecainide and subsequent early electrophysiological studies and successful ablation.</AbstractText>Initiation of oral Flecainide in a case of atrial fibrillation with subjective improvement and regular ECG monitoring, no QTc prolongation can still lead to development of dangerous ventricular arrhythmias. A cautious approach and thorough investigations and follow up are recommended.</AbstractText> |
9,955 | Incidence of arrhythmias in a large cohort of patients with current implantable cardioverter-defibrillators in Spain: results from the UMBRELLA Registry. | The benefit of implantable cardioverter-defibrillators (ICDs) in patients at risk of sudden death has been established in randomized clinical trials (RCTs) using the ICD models available at the time. However, observational large-scale data on the incidence of arrhythmias in up-to-date ICDs implanted according to the current guidelines are scarce. The aim was to assess the incidence of arrhythmias in a large, current ICD population based on a blinded peer review of the detected episodes.</AbstractText>UMBRELLA is a multicentre, observational registry of ICD patients followed by remote monitoring. Stored episodes were classified by a blinded committee of experts. Subgroup analyses were based on clinical profiles established by previous pivotal RCTs of ICDs. Of 1514 enrolled patients, 605 (39.9%) patients had 5951 episodes after 26 ± 17 months follow-up, being 3353 of them (56.3%) sustained ventricular arrhythmias (SVA), and 13.2% of SVA were self-terminated. Appropriate and inappropriate shocks occurred in 11.6 and 5% of patients, respectively. The 3 years cumulative incidence of SVA was 25% (95% CI: 21-28%) in primary prevention patients and 41% (95% CI: 36-47%) in secondary prevention patients (P < 0.001). Male gender, secondary prevention, and atrial fibrillation as basal rhythm were significantly related to a higher incidence of SVA.</AbstractText>This real-world analysis suggests that modern ICD patients have a low rate of appropriate and inappropriate shocks. The risk of SVA in secondary prevention patients is less than what has been reported in RCTs.</AbstractText>Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2015. For permissions please email: journals.permissions@oup.com.</CopyrightInformation> |
9,956 | Sensor fusion methods for reducing false alarms in heart rate monitoring. | Automatic patient monitoring is an essential resource in hospitals for good health care management. While alarms caused by abnormal physiological conditions are important for the delivery of fast treatment, they can be also a source of unnecessary noise because of false alarms caused by electromagnetic interference or motion artifacts. One significant source of false alarms is related to heart rate, which is triggered when the heart rhythm of the patient is too fast or too slow. In this work, the fusion of different physiological sensors is explored in order to create a robust heart rate estimation. A set of algorithms using heart rate variability index, Bayesian inference, neural networks, fuzzy logic and majority voting is proposed to fuse the information from the electrocardiogram, arterial blood pressure and photoplethysmogram. Three kinds of information are extracted from each source, namely, heart rate variability, the heart rate difference between sensors and the spectral analysis of low and high noise of each sensor. This information is used as input to the algorithms. Twenty recordings selected from the MIMIC database were used to validate the system. The results showed that neural networks fusion had the best false alarm reduction of 92.5 %, while the Bayesian technique had a reduction of 84.3 %, fuzzy logic 80.6 %, majority voter 72.5 % and the heart rate variability index 67.5 %. Therefore, the proposed algorithms showed good performance and could be useful in bedside monitors. |
9,957 | ECG as a first step in the detection of left ventricular systolic dysfunction in the elderly. | Due to the demographic development there is an increasing number of senior citizens with left ventricular systolic dysfunction (LVSD), defined as ejection fraction (EF) < 40%. Unfortunately there are under-diagnosis and under-treatment in the elderly of this serious condition. Echocardiography is the gold standard to diagnose LVSD, but access is limited. Simple screening methods may ensure reduction of undetected cases, and this study investigates if electrocardiogram (ECG) can be used to screen for LVSD in the geriatric population.</AbstractText>A total of 260 persons aged 75 to 92 years had an echocardiography, a 12 leads ECG, and NT-proBNP; 61 had EF < 40%, and of these 60 had an abnormal ECG. EF < 40% was significantly related to atrial fibrillation (A), pacing (P), LBBB (L), Q-waves (Q), and QRS duration ≥ 120 ms (D). EF < 40%, atrial fibrillation, pacing, and LBBB were related to NT-proBNP > 35 pmol/L. When APL was absent, NT-proBNP had discriminatory value regarding LVSD in the presence of Q-waves or QRS duration > 120 ms. Algorithms to screen for LVSD had sensitivity >90% and specificity >80% and claimed at least one of five (A/P/L/Q/D), one of 4 (A/P/L/Q), or one of three (A/Q/D) ECG changes. The optimal algorithm to reduce the need for diagnostic echocardiographies included four (A/P/L/Q) ECG changes and measurement of NT-proBNP when Q-waves were the only ECG change present.</AbstractText>Ninety percent of LVSD may be detected, and when there is atrial fibrillation, pacing or LBBB, or QRS ≥ 120 ms/Q-waves and NT-proBNP>35 pmol/L, a diagnostic echocardiography should be considered.</AbstractText> |
9,958 | Autonomic and cardio-respiratory responses to exercise in Brugada Syndrome patients. | Imbalances of the autonomic nervous (ANS), the cardiovascular system, and ionics might contribute to the manifestation of The Brugada Syndrome (BrS). Thus, this study has aimed to investigate the cardio-respiratory fitness and the responses of the ANS both at rest and during a sub-maximal exercise stress test, in BrS patients and in gender-matched and age-matched healthy sedentary controls.</AbstractText>Eleven BrS patients and 23 healthy controls were recruited in Khon Kaen, Thailand. They performed an exercise test on a cycle ergometer, and during the exercise, expired gas samples and electrocardiograms were collected. Blood glucose and electrolyte concentrations were analyzed before and after exercise. Then the heart rate variability (HRV) and the heart rate recovery (HRR) were analyzed from the electrocardiograms.</AbstractText>The BrS patients showed a higher parasympathetic activation during exercise recovery than baseline. They had a smaller level of sympathetic activation during the period of exercise recovery than the controls did. They also showed a significantly lower peak HR, HRR, and peak oxygen consumption than the controls (p</i><0.05). All subjects had a significantly lower percentage of peak oxygen consumption and respiratory exchange ratio during low-intensity (p</i><0.01) and moderate-intensity (p</i><0.05) exercise than during high-intensity exercise. The BrS patients had mild hyperkalemia which is reduced according to the exercise.</AbstractText>Thai BrS patients had a more rapid rate of restoration of the parasympathetic and smaller level of sympathetic activation after exercise. They had mild hyperkalemia which is reduced according to the exercise. Furthermore, they exhibited impaired cardio-respiratory fitness.</AbstractText> |
9,959 | Congenitally unguarded tricuspid valve orifice with right ventricular apical isolation in an adult. | Congenitally unguarded tricuspid valve (TV) orifice, a variant of TV dysplasia, is a rare malformation with protean manifestations. This report describes a symptomatic adult male with gross right heart failure and atrial fibrillation, who was found to have an unguarded TV orifice with isolation of the trabecular apical cavity of the right ventricle (RV) and muscular ridges separating outflow tract (forme-fruste of the double-chambered RV). The right ventricular outflow tract remained patent. |
9,960 | Citalopram-Induced Long QT Syndrome and the Mammalian Dive Reflex. | While SCUBA diving, a 44-year-old Caucasian patient had an abnormal cardiac rhythm, presumably Torsade de Pointes (TdP), during the initial descent to depth. Upon surfacing, she developed ventricular fibrillation and died. The patient had been treated for mild depression for nearly a year with citalopram 60 mg per day, a drug known to cause prolonged QT interval. She had also been treated with two potentially hepatotoxic drugs. Liver impairment causes selective loss of cytochrome P450 (CYP) 2C19 activity, the major pathway for metabolism of citalopram. The post mortem blood level of citalopram was 1300 ng/mL. The patient was found to be an intermediate metabolizer via CYP2D6, the major pathway for metabolism of desmethylcitalopram; the level of which was also abnormally high. It is suggested that drug-induced long QT syndrome (DILQTS), caused by citalopram, combined with the mammalian dive reflex triggered malignant ventricular rhythms resulting in the patient's death. It is further suggested that, in general, the dive reflex increases the risk of fatal cardiac rhythms when the QT interval is prolonged by drugs. |
9,961 | Early Amiodarone-Induced Pulmonary Toxicity after Endovascular Aneurysm Repair: A Case Report. | Amiodarone is an antiarrhythmic drug that has been commonly used to treat supraventricular and ventricular arrhythmias. This drug is an iodine-containing compound that tends to accumulate in several organs, including the lungs. Especially, its main metabolically active metabolite desethylamiodarone can adversely affect many organs. A very well-known severe complication of amiodarone therapy is the amiodarone-induced pulmonary toxicity. This article presents the case study of an 82-year-old male patient with acute amiodarone-induced pulmonary toxicity. The patient underwent endovascular aneurysm repair for rapidly increasing abdominal aortic aneurysm. During the postoperative period the patient developed rapid atrial fibrillation and amiodarone therapy was initiated. Subsequently, the patient went into acute respiratory failure and was requiring high supplemental oxygen support and a chest X-ray revealed bilateral pulmonary infiltrates. During the hospital course the patient required mechanical ventilator support. With discontinuation of amiodarone, supportive therapy and steroid treatment patient symptoms significantly improved. Amiodarone-induced pulmonary toxicity must be considered in the differential diagnosis of all patients on the medication with progressive or acute respiratory symptoms. Early discontinuation of amiodarone and aggressive corticosteroid therapy should be considered as a viable treatment strategy. |
9,962 | Mechanical Chest Compressions in Prolonged Cardiac Arrest due to ST Elevation Myocardial Infarction Can Cause Myocardial Contusion. | Acute coronary syndrome is a common cause of sudden cardiac death. We present a case report of a 60-year-old man without a history of coronary artery disease who presented with ST-elevation myocardial infarction. During transportation to the hospital, he developed ventricular fibrillation (VF) and later pulseless electrical activity. Chest compressions with LUCAS 2 (Medtronic, Minneapolis, MN) automated mechanical compression-decompression device were initiated. Coronary angiography showed total occlusion of the left main coronary artery and primary percutaneous coronary intervention (PCI) was performed. After the PCI, his heart started to generate effective contractions and LUCAS could be discontinued. Return of spontaneous circulation was achieved after 90 minutes of cardiac arrest. The patient died of cardiogenic shock 11 hours later. An autopsy revealed a transmural anterolateral myocardial infarction but also massive subepicardial hemorrhage and interstitial edema and hemorrhages on histologic samples from regions of the myocardium outside the infarction itself and also from the right ventricle. These lesions were concluded to be a myocardial contusion. The true incidence of myocardial contusion as a consequence of mechanical chest compressions is not known. We speculate that severe myocardial contusion might have influenced outcome of our patient. |
9,963 | Salbutamol Abuse is Associated with Ventricular Fibrillation. | Salbutamol-induced cardiac complications are well-established. Herein, we describe a case of a 24-year female who was admitted to the emergency department because of a suicide attempt with salbutamol (76 mg). Salbutamol abuse induced the development of supraventricular tachycardia and ventricular fibrillation. Regular sinus rhythm was restored with defibrillation. The hypokalemic patient who stayed in the intensive care unit was discharged after 48 hours of hospitalization. |
9,964 | [Regularity of agonal respiration after untreated cardiac arrest in a swine model]. | To explore the regularity of incidence of agonal respiration (AR) and agonal respiration frequency rate (ARFR) during untreated cardiac arrest (CA) after ventricular fibrillation (VF) in a swine model.</AbstractText>Ten healthy male domestic pigs weighing (25.0 ± 3.0) kg were employed in this experiment. VF was induced by intraventricular shock with alternating current without treatment for 8 minutes. The incidence of AR and ARFR per minute were recorded for 8 minutes. Statistical analysis was performed using SPSS 19.0 system software.</AbstractText>AR occurred in all animals after VF induced CA within 8 minutes. There was 1 animal showed AR at the first minute with ARFR (0.2 ± 0.1) times/min, 4 animals showed AR at the second minute with ARFR (1.2 ± 1.0) times/min, 7 animals showed AR at the third minute with ARFR (2.7 ± 1.4) times/min, all animals showed AR at the fourth to fifth minute with ARFR (3.7 ± 1.6) times/min and (3.2 ± 1.9) times/min, 7 animals showed AR at the sixth minute with ARFR (1.3 ± 1.0) times/min, no animal showed AR at the seventh minute, and 1 animal showed AR at the eighth minute with ARFR (0.2 ± 0.1) times/min. The first and the last AR were observed at (2.02 ± 0.84) minutes and (5.21 ± 1.12) minutes respectively. Occurrence of AR reached its peak at the fourth to fifth minute, and it was absent at the seventh minute. ARFR after CA showed a crescendo-decrescendo pattern, which increased from (0.2 ± 0.1) times/min to (3.7 ± 1.6) times/min followed by a fall to (0.2 ± 0.1) times/min.</AbstractText>AR is one of the symbolic signs after CA. AR occurred in all animals during untreated VF, and it reaches its peak at the fourth to fifth minute, with a crescendo-decrescendo pattern of ARFR. Effective identification and treatment in victim with AR timely can help to improve the success rate of cardiopulmonary resuscitation and survival rate.</AbstractText> |
9,965 | [Effects and risks of hypothermia during blood purification in the treatment of postoperative cardiogenic shock in valvular heart diseases]. | To implement hypothermia during blood purification to investigate its effect and risk in the treatment of postoperative cardiogenic shock in valvular heart disease.</AbstractText>A non-blinded prospective randomized controlled trial (RCT) was conducted. Patients with valvular heart disease suffering from postoperative cardiogenic shock admitted to intensive care unit (ICU) of Wuhan Asian Heart Hospital from January 2011 to December 2014 were enrolled, and they were randomly divided into normothermic continuous blood purification (CBP) group (NT group) and hypothermia CBP group (HT group) according to random number table and envelope enclosed method. The patients in both groups were given continuous renal replacement therapy (CVVH), the blood temperature in NT group was remained at 36.5-37.3 °C , and it was controlled at 34.0-35.0 °C in HT group. The data were collected before and 1, 2, 3 days after treatment, including cardiac index (CI), the oxygen supply/oxygen consumption ratio (DO₂/VO₂), acute physiology and chronic health evaluation III (APACHE III) score, multiple organ dysfunction (MODS) score. The length of ICU stay, duration of mechanical ventilation, duration of CBP, ICU mortality and the incidence of complication were recorded.</AbstractText>A total of 95 patients were enrolled, with 47 patients in NT group, and 48 in HT group. There was no significant difference in gender, age, preoperative cardiac function, cardiothoracic ratio and type of valve replacement between two groups. Compared with those before treatment, no significant difference was found in CI, DO₂/VO₂ ratio, APACHE III score, MODS score on 1, 2, 3 days after treatment in NT group (all P > 0.05). But in HT group, DO₂/VO₂ ratio was significantly improved on 1 day after treatment (2.5 ± 0.7 vs. 1.8 ± 0.4, P < 0.05), CI (mL · s⁻¹ · m⁻²: 50.01 ± 8.34 vs. 31.67 ± 11.67), APACHE III score ( 50.6 ± 6.2 vs. 77.5 ± 5.5), and MODS score (6.0 ± 1.5 vs. 9.3 ± 3.4) were significantly improved 3 days after treatment (all P < 0.05). Compared with those in NT group, DO₂NO2 ratio in HT group was significantly increased from 1 day after treatment (2.5 ± 0.7 vs. 1.8 ± 0.4, P < 0.05), and CI (mL · s⁻¹ · m⁻²: 38.34 ± 10.00 vs. 35.01 ± 6.67), APACHE III score (68.9 ± 7.1 vs. 81.2 ± 7.3), and MODS score (8.9 ± 2.7 vs. 10.6 ± 2.4) were significantly improved from 2 days after treatment (all P < 0.05). In respect of clinical outcomes, compared with NT group, the length of ICU stay (days: 6.9 ± 3.4 vs. 12.5 ± 3.5, t = 2.024, P = 0.017) and duration of mechanical ventilation (days: 4.2 ± 1.3 vs. 7.5 ± 2.7, t = 1.895, P = 0.034) in HT group was significantly shortened, duration of CBP was also significantly shortened (days: 4.6 ± 1.4 vs. 10.5 ± 4.0, t = 2.256, P = 0.019), and ICU mortality was significantly lowered (12.50% vs. 23.40, χ² = 1.987, P = 0.024), but there was no significant difference in incidence of infection (54.17% vs. 53.19%, χ² = 0.689, P = 0.341), ventricular arrhythmia (31.25% vs. 36.17%, χ² = 0.772, P = 0.237), and muscle fibrillation (14.58% vs. 8.51%, χ² = 0.714, P = 0.346), and blood loss (mL: 617.0 ± 60.7 vs. 550.9 ± 85.2, t = 1.290, P = 0.203) between HT group and NT group. The incidence of bradycardia in HT group was significantly higher than that of the NT group (29.17% vs. 14.89%, χ² = 2.368 P = 0.029).</AbstractText>Blood purification under hypothermia is a safe and effective therapeutic procedure for postoperative cardiogenic shock in patients with valvular heart disease, and it may improve the prognosis of postoperative patients.</AbstractText> |
9,966 | Heart Failure with Preserved Ejection Fraction - Concept, Pathophysiology, Diagnosis and Challenges for Treatment. | Heart failure (HF) with preserved left ventricular (LV) ejection fraction (HFpEF) occurs in 40 to 60% of the patients with HF, with a prognosis which is similar to HF with reduced ejection fraction (HFrEF). HFpEF pathophysiology is different from that of HFrEF, and has been characterized with diastolic dysfunction. Diastolic dysfunction has been defined with elevated left ventricular stiffness, prolonged iso-volumetric LV relaxation, slow LV filing and elevated LV end-diastolic pressure. Arterial hypertension occurs in majority cases with HFpEF worldwide. Patients are mostly older and obese. Diabetes mellitus and atrial fibrillation appear proportionally in a high frequency of patients with HFpEF. The HFpEF diagnosis is based on existence of symptoms and signs of heart failure, normal or approximately normal ejection and diagnosing of LV diastolic dysfunction by means of heart catheterization or Doppler echocardiography and/or elevated concentration of plasma natriuretic peptide. The present recommendations for HFpEF treatment include blood pressure control, heart chamber frequency control when atrial fibrillation exists, in some situations even coronary revascularization and an attempt for sinus rhythm reestablishment. Up to now, it is considered that no medication or a group of medications improve the survival of HFpEF patients. Due to these causes and the bad prognosis of the disorder, rigorous control is recommended of the previously mentioned precipitating factors for this disorder. This paper presents a universal review of the most important parameters which determine this disorder. |
9,967 | Cardiac Resynchronization Therapy May Be Antiarrhythmic Particularly in Responders: A Systematic Review and Meta-Analysis. | This study sought to study the effect of echocardiographic response to cardiac resynchronization therapy (CRT) on ventricular arrhythmias (VA). The effect of CRT-defibrillator on sustained VA was compared with implantable cardioverter-defibrillator (ICD)-only therapy.</AbstractText>CRT is an effective adjunctive therapy in selected patients with advanced congestive heart failure, but its effect on VA remains controversial.</AbstractText>PubMed was searched to identify studies. For primary comparison, studies reporting incidence of VA in patients with congestive heart failure with CRT compared with ICD were included. For secondary comparison, studies reporting incidence of VA in echocardiographic responders compared with nonresponders were included. Studies reporting incidence of VA in CRT nonresponders before and after CRT upgrade from ICD were assessed for the third comparison. Inverse variance method in a random-effects model was used to combine effect sizes.</AbstractText>Thirteen studies (4,631 subjects) were included in the primary meta-analysis. Patients with CRT had a significantly lower incidence of VA compared with patients with ICD only (odds ratio: 0.754; confidence interval: 0.594 to 0.959). Thirteen studies (n = 3,667) were included in the meta-analysis of VA in CRT responders versus nonresponders. Responders had a significantly lower risk of VA (odds ratio: 0.436; confidence interval: 0.323 to 0.589). Multivariate meta-regression showed that the percentage beta-blocker use and follow-up duration explained heterogeneity between the studies. Three studies were included in the comparison of VA in CRT nonresponders before and after upgrade from ICD. CRT nonresponders had an elevated risk of VA compared with ICD-only subjects (odds ratio: 1.497; confidence interval: 1.225 to 1.829).</AbstractText>CRT may significantly reduce risk of VA compared with ICDs in patients who meet criteria for CRT. CRT responders have significant reduction in VA compared with nonresponders. CRT nonresponse might significantly increase risk of VA.</AbstractText>Copyright © 2016 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.</CopyrightInformation> |
9,968 | Right Ventricular Pacing-Induced Heart Failure after Mitral Valve Replacement. | It is an unfortunate fact that pacing-induced heart failure after cardiac surgery is frequently ignored by medical professionals. A 60-year-old woman with chronic atrial fibrillation with a single-lead right ventricular permanent pacemaker for a prolonged ventricular pause underwent mitral valve replacement 6 months later for severe stenosis (NYHA functional class III). The patient's pacing rate was increased from the preoperative level of 60 beats per minute (bpm) to 70 bpm in order to facilitate weaning from the cardiopulmonary bypass. However, her postoperative low cardiac output continued to progress, despite the presence of inotropes. The patient's cold limbs and oliguria persisted until she underwent echocardiographic imaging, which showed dyssynchronous ventricular contraction 29 days post-surgery but which improved after the pacing rate was reduced below her spontaneous rate. Ultimately, clinicians should exercise caution when increasing right ventricular pacing for postoperative stunned myocardium. Due to the problems that can arise from an increased pacing rate, postoperative pacing strategy in patients complicated with low cardiac output after mitral valve replacement merits further discussion.</AbstractText>Dyssynchrony; Mitral valve replacement; Right ventricular pacing; Stunned myocardium.</AbstractText> |
9,969 | [Antiarrhythmic effect of oligonucleotides accompanied by activation of HSP70 protein in the heart of rats]. | The mechanisms of the protective effect of oligonucleotides (OGN) during pathological processes are poorlyunderstood. The goal of this work was to study the effect of OGN on arrhythmias induced by myocardial ischemia and reperfusion, and the HSP70 level in the heart. As a source of OGN was used the drug "Derinat" ("Technomedservis", Russia). In male Wistar rats were pre-treated the drug for 7 days (i/m, 7.5 mg/kg).The intensity of the arrhythmias was assessed by ECG during 10 min occlusion of the left coronary artery and subsequent 5 min of reperfusion. Protein HSP70 determined in the left ventricle of the heart by Western-blot analysis. During ischemia, this drug reduced duration of extrasystolia by 13 times and the incidence of ventricular tachycardia by 1.5 times. During reperfusion the drug reduced the incidence of ventricular fibrillation, a more than 2-fold, as compared with the control (respectively 23% vs 56%) and by 5 times its duration (8,4 ± 2,3 48,1 ± sec vs 18 7 sec). "Derinat" increased the HSP70 level in the heart by 65% compared with control.</AbstractText>These data support the fact that the activation of HSP70 synthesis, induced by OGN is one of the mechanisms that increases the heart resistance to the ischemic and reperfusion damages.</AbstractText> |
9,970 | Practical applicability of landiolol, an ultra-short-acting β1-selective blocker, for rapid atrial and ventricular tachyarrhythmias with left ventricular dysfunction. | Landiolol effectively controls rapid heart rate in atrial fibrillation or flutter (AF/AFL) patients with left ventricular (LV) dysfunction. However, predicting landiolol Responders and Non-Responders and patients who will experience adverse effects remains a challenge. The aim of this study was to clarify the potential applicability of landiolol for rapid AF/AFL and refractory ventricular tachyarrhythmias (VTs) in patients with heart failure.</AbstractText>A total of 39 patients with AF/AFL with ventricular response ≥120 bpm and 12 VTs were retrospectively enrolled. Landiolol Responders for rapid AF/AFL were defined as patients whose ventricular response was suppressed to less than 110 bpm or decreased by ≥20% from the initial heart rate after administration of landiolol. Responders for VTs were defined as patients with no recurrent VTs during the 24 h after the initiation of landiolol.</AbstractText>For AF/AFL, 29 patients (74%) were Responders. In nine patients (31%), AF was spontaneously terminated after starting landiolol. Eight Non-Responders (80%) needed to have AF terminated by cardioversion. Left ventricular ejection fraction (LVEF) at baseline was significantly associated with landiolol efficacy. For VTs, seven patients (58%) were Responders, and smaller LV diastolic and systolic diameters were associated with landiolol efficacy. Hypotension after landiolol treatment occurred in 5 of 51 patients, and lower LV systolic function was associated with the development of adverse events.</AbstractText>Landiolol is effective in patients with heart failure not only due to rapid AF/AFL but also due to VTs. However, preserved LVEF is important for efficacy and safety in landiolol treatment.</AbstractText> |
9,971 | [Wearable Automatic External Defibrillators]. | Defibrillation is the most effective method of treating ventricular fibrillation(VF), this paper introduces wearable automatic external defibrillators based on embedded system which includes EGG measurements, bioelectrical impedance measurement, discharge defibrillation module, which can automatic identify VF signal, biphasic exponential waveform defibrillation discharge. After verified by animal tests, the device can realize EGG acquisition and automatic identification. After identifying the ventricular fibrillation signal, it can automatic defibrillate to abort ventricular fibrillation and to realize the cardiac electrical cardioversion. |
9,972 | Characteristics of syncope in patients with dilated cardiomyopathy. | Syncope carries a poor prognosis among patients with dilated cardiomyopathy (DCM).</AbstractText>To assess the prevalence, describe the underlying mechanisms and to identify risk factors for syncope in patients with DCM.</AbstractText>One thousand six hundred and ten medical files of 897 patients with a diagnosis of DCM were reviewed. Patients with syncope were identified and their clinical and paraclinical profiles were compared to an equal number of age- and sex-matched patients with DCM without syncope.</AbstractText>Thirty patients (27 males) with an average age of 62.5 years were identified, corresponding to a prevalence of syncope of 3.3%. A cardiac origin of syncope was identified in 56% of patients (n=17): ventricular arrhythmias in 33% (n=10), and conduction disorders in 23% (n=7). Other mechanisms of syncope were neurally mediated in 7% (n=2) and orthostatic hypotension in 7% (n=2). In 30% of cases (n=9), the etiology was unidentified. There were no significant differences regarding the etiology of DCM, ejection fraction (35.3% vs 35.3%, p=1.0), NYHA class (mild or advanced, p=0.79) and associated conditions (hypertension, p=0.36; diabetes, p=0.75; atrial fibrillation, p=0.43; and dyslipidemia, p=0.33) between the two groups. However, among patients with syncope, patients with a noncardiac cause were more likely to have hypertension (61.53% vs 23.52%, p=0.08) and diabetes (46.15% vs 5.88%, p=0.03).</AbstractText>In patients with DCM, syncope is a relatively rare finding. Cardiac causes (arrhythmias and conduction disorders) are responsible for the majority of cases. Risk factors for syncope in these patients remain to be determined.</AbstractText>Copyright © 2015 Cardiological Society of India. Published by Elsevier B.V. All rights reserved.</CopyrightInformation> |
9,973 | N-terminal-pro-brain natriuretic peptide, a surrogate biomarker of combined clinical and hemodynamic outcomes following percutaneous transvenous mitral commissurotomy. | To examine the relationship between plasma levels of N-terminal-proB type natriuretic peptide (NT-proBNP) and various echocardiographic and hemodynamic parameters in patients with mitral stenosis undergoing percutaneous transvenous mitral commissurotomy (PTMC).</AbstractText>The study population consisted of 100 patients with rheumatic mitral stenosis who underwent PTMC. NT-proBNP levels in these patients were measured before PTMC and 48 hours after PTMC. These levels were then correlated with various echocardiographic and hemodynamic parameters measured before and after PTMC.</AbstractText>Eighty-one percent of the study population were women, and the most common presenting symptom was dyspnea which was present in 94% of the patients. Dyspnea New York Heart Association class correlated significantly with baseline NT-proBNP levels (r = 0.63; p < 0.01). The plasma NT-proBNP levels in these patients increased as echocardiogram signs of left atrial enlargement and right ventricular hypertrophy developed (r = 0.59, p < 0.01). Patients in atrial fibrillation had significantly higher NT-proBNP levels than patients in sinus rhythm. Baseline NT-proBNP levels correlated significantly with left atrial volume (r = 0.38; p < 0.01), left atrial volume index (r = 0.45; p < 0.01), systolic pulmonary artery pressures (r = 0.42; p < 0.01), and mean pulmonary artery pressures (r = 0.41; p < 0.01). All patients who underwent successful PTMC showed a significant decrease in NT-proBNP (decreased from a mean 763.8 pg/mL to 348.6 pg/mL) along with a significant improvement in all echocardiographic and hemodynamic parameters (p < 0.01). The percent change in NT-proBNP correlated significantly with the percent improvement noted with left atrial volume (r = 0.39; p < 0.01), left atrial volume index (r = 0.41; p < 0.01), systolic (r = 0.32, p < 0.01), and mean pulmonary artery pressures (r = 0.31, p < 0.01).</AbstractText>The decrease in NT-proBNP levels following PTMC reflects an improvement in clinical and hemodynamic status; hence, it is reasonable to suggest that NT-proBNP is helpful in evaluating the response to PTMC.</AbstractText> |
9,974 | Global Survey of Esophageal Injury in Atrial Fibrillation Ablation: Characteristics and Outcomes of Esophageal Perforation and Fistula. | This study sought to assess the incidence, operator demographics, clinical characteristics, procedural factors, and prognosis of esophageal perforation and fistula after atrial fibrillation ablation.</AbstractText>Esophageal injury is a feared complication of atrial fibrillation ablation.</AbstractText>An Internet-based global survey soliciting anonymous information regarding esophageal perforation and fistula was emailed to 3,080 physicians. Detailed information regarding physician, patient, and procedural characteristics related to esophageal perforation with or without fistula was collected.</AbstractText>The survey was completed by 405 of 3,080 physicians (13%). Responding physicians performed 191,215 atrial fibrillation ablations and esophageal perforation with or without fistula occurred in 31 patients (0.016%) with multiple ablation catheter types despite monitoring of esophageal position or temperature during ablation in 90% of patients. Among patients who present with esophageal perforation, death, or severe neurologic injury occurred more frequently in patients with greater body mass index (30.9 ± 6.8 kg/m2</sup> vs. 25.8 ± 3.3 kg/m2</sup>; p = 0.03), and lower left ventricular ejection fraction (55.1 ± 9.1% vs. 61.7 ± 5.4%; p = 0.04). Among analyzed patients, atrial-esophageal fistula was seen in 72%, pericardial-esophageal fistula in 14%, and esophageal perforation without fistula in 14%. Mortality was 79% with atrial-esophageal fistula and 13% in esophageal perforation without atrial-esophageal fistula.</AbstractText>Esophageal perforation is rare but continues to occur with multiple catheter types despite esophageal monitoring during ablation. The prognosis of esophageal perforation is substantially improved if diagnosed and treated before development of atrial-esophageal fistula. An early surgical approach to esophageal perforation should be strongly considered regardless of evidence of fistula.</AbstractText>Copyright © 2016 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.</CopyrightInformation> |
9,975 | Neopterin and interleukin-6 as predictors of recurrent atrial fibrillation. | Available evidence suggests that inflammation may be associated with atrial fibrillation (AF). This prospective and observational study aimed to assess whether plasma neopterin (NPT) and interleukin-6 (IL-6) levels before and after electrical cardioversion (CV) predict AF recurrence.</AbstractText>The study was designed as a prospective observational trial. Blood samples were collected (24 hours before, 24 h after CV, and 7 days after CV) in 60 patients with a dual-chamber pacemakar and preserved left ventricular systolic function who underwent successful CV of persistent AF. All significant parameters associated with AF recurrence lasting ≥30 min and detected by pacemaker data logs were evaluated in multivariate logistic regression analysis. Echocardiography was performed 7 days after CV in patients with sinus rhythm. The control group included 17 subjects without AF.</AbstractText>The analysis included 51 patients who remained in sinus rhythm 7 days after CV. During 12 months of follow-up, AF recurred in 46 patients. Baseline IL-6 levels did not differ between the two groups, but baseline NPT levels were higher in the study group than in the control group (19±7 vs. 11±5 nmol/mL, p<0.001). NPT levels of ≥14.6 nmol/L at baseline and ≥13.3 nmol/L 7 days after CV separated the patients with AF recurrence from those without arrhythmia after CV. Only left atrial emptying fraction <38% was an independent predictor of AF recurrence (p=0.03), whereas NPT levels of ≥13.3 nmol/L 7 days after CV showed borderline statistical significance (p=0.07).</AbstractText>Increased NPT level was observed in patients with persistent AF. Neither baseline IL-6 and NPT levels nor their changes within 7 days after CV were predictive of AF recurrence. Further studies are needed to establish the prognostic significance of NPT in patients with AF.</AbstractText> |
9,976 | [Placenta percreta--a severe obstetric complication despite correct diagnosis--a case report]. | This paper presents a case of a pregnant woman with a history of two cesarean sections. The patient was admitted to the hospital because of vaginal bleeding. The ultrasound revealed a placenta covering the internal os. The placenta was characterized by heterogeneous echogenicity with visible irregular hypoechogenic areas and blurred border between the placenta and the cervix. Rich vascularity was observed on the border of the placenta, urethra and the urinary bladder. Cystoscopy showed severe congestion around the urethra. On the back wall of the bladder a slightly increased vascularity was seen, which did not allow to confirm or exclude placental ingrowth in the urinary bladder. At 38 weeks, the patient was scheduled for an elective cesarean section. A classic perpendicular incision and leaving the placenta in the uterine cavity were proposed. After opening the abdomen, a strong vascularization in the region of lower part of the uterus and the urinary bladder was seen. Uterine incision in the fundus and the posterior wall was performed. A female fetus (weight: 2950g, Apgar: 10,10) was born. Then, the umbilical cord was ligated with non-absorbable suture and inserted back into the uterus. However, due to the presence of abundant and persistent vaginal bleeding during the next few minutes, conversion to obstetric hysterectomy was required. During relaparotomy fragments of the placenta appeared on the right side after sliding the urinary bladder. The bladder and the left ureter were damaged during surgery. The urinary bladder was sewn after removal of the uterus. Next, the urologist anastomosed end-to-end the left ureter on the pigtail catheter In the third hour of operation, cardiac arrest was caused by ventricular fibrillation. Immediate resuscitation with defibrillation allowed to restore normal function of the cardiovascular system. Total blood loss during the operation was 3000-4000 ml. During surgery 10 units of packed RBCs, 7 units of fresh frozen plasma, and 4 units of cryoprecipitate were transfused. The patient received antibiotics and anticoagulation therapy. Polyuria was diagnosed in the following days of puerperium, accompanied by electrolyte disturbances in serum and urine. The patient was treated with vasopressin and the electrolyte disturbances were corrected. On day 10 postpartum, the urinary catheter was removed, and clear significant improvement and stabilization of renal function and patient health were obtained. The patient was discharged from the hospital on day 19 of the puerperium. In summary it is clear that the steadily increasing rate of cesarean deliveries may result in the future in an increased number of abnormal placentation cases. Abnormal placentation is one of the most important risk factors of severe obstetric complications, including perinatal massive hemorrhage, which can lead to abnormal organ perfusion with cardiac arrest. Therefore, prenatal diagnosis and identification of abnormal placentation are vital in order to plan adequately the date, place, and mode of delivery as well as to ensure the availability of highly qualified specialists in the field of obstetrics and anesthesia, and organize sufficient amount of blood products and blood substitutes. |
9,977 | [Long-term outcome after cardioverter-defibrillator implantation in patients with Brugada syndrome]. | To observe the long-term outcome of implantable cardioverter-defibrillator (ICD) implantation in Brugada syndrome patients and to explore how to reduce the frequency of ICD nappropriate schocks.</AbstractText>This study included 14 symptomatic patients (mean age (44.3 ± 8.3) years old; all males) with Brugada syndrome implanted with ICD in our hospital between 1998 and 2012, and these patients were followed up routinely every 6 months. The initial ICD parameters were set according o conventional experience. The ventricular tachycardia (VT) zone was programmed to ventricular rate 150-188 bpm/cycle length (CL) 400-320 ms and the ventricular fibrillation (VF) zone was programmed to ventricular rate ≥ 188 bpm/CL ≤ 320 ms. The total events were recorded by ICD. The ICD parameters revision was made by electrophysiological (EP) experts in case of inappropriate shocks.</AbstractText>Patients were followed up for mean (43.0 ± 28.3) months. A total of 297 VF/VT events were recorded by ICD. Electrophysiological experts found that 90% (178/198) episodes were true VF ( CL 130-250 ms) among of 198 VF episodes and 147 VF episodes were terminated by one shock and 21 VF events were terminated by two or more shocks, and the rest 10 VF terminated spontaneously. Only 9% (9/99) VT events were true VT (CL 320-360 ms) among of 99 VT episodes. Eight VT episodes were converted by antitachycardia pacing therapy (ATP) and the other one terminated spontaneously. The rest 90 VT episodes (91%) were supraventricular arrhythmias (SVT, CL 340-390 ms). About 90% inappropriate shocks can be reduced by Wavelet discrimination function and optimal programming (VF zone ventricular rate ≥ 222 bpm/CL ≤ 270 ms and/or VT zone ventricular rate 167-222 bpm/CL 270-360 ms ) according to the characteristics of arrhythmia of individual patient.</AbstractText>ICD can effectively prevent sudden cardiac death and syncope in high-risk patients with Brugada syndrome. The most common complication is inappropriate shock due to SVT. Optimal ICD programming with Wavelet discrimination function can effectively reduce the frequency of inappropriate shock rate.</AbstractText> |
9,978 | An overlap of Brugada syndrome and arrhythmogenic right ventricular cardiomyopathy/dysplasia. | Overlapping characteristics of Brugada syndrome (BrS) and arrhythmogenic right ventricular cardiomyopathy/dysplasia (ARVC/D) have been reported in recent studies, but little is known about the overlapping disease state of BrS and ARVC/D. A 36-year-old man, hospitalized at our institution for syncope, presented with this overlapping disease state. The electrocardiogram showed spontaneous coved-type ST-segment elevation, and ventricular fibrillation was induced by right ventricular outflow tract stimulation in an electrophysiological study. BrS was subsequently diagnosed; additionally, the presence of epsilon-like waves and right ventricular structural abnormalities met with the 2010 revised task force criteria for ARVC/D. After careful investigation for both BrS and ARVC/D, an implantable cardioverter defibrillator was inserted in the patient. This case revealed 2 important clinical findings: (1) BrS and ARVC/D clinical features can coexist in a single patient, and EPS might be useful for determining the phenotype of overlapping disease (e.g., BrS-like or ARVC/D-like). (2) An overlapping disease state of BrS and ARVC/D can change phenotypically during its clinical course. Therefore, careful examination and attentive follow-up are required for patients with BrS or ARVC/D. |
9,979 | An appropriate shock of the wearable cardioverter-defibrillator in an outpatient setting. | The wearable cardioverter-defibrillator (WCD) represents an alternative clinical approach to prevent sudden cardiac death as a bridge to therapy when making a final decision regarding the need for an implantable cardioverter defibrillator (ICD), especially in patients who are in the so-called gray zone according to ICD guidelines. Although the WCD system was introduced in Japan in April 2014, data regarding its usage and experience are limited. We report the first case of appropriate shock therapy using the WCD in an outpatient setting in Japan. We describe the case of a 22-year-old-woman who received the first case of successful appropriate WCD shock therapy in an outpatient setting in Japan. |
9,980 | Measurement of diffuse ventricular fibrosis with myocardial T1 in patients with atrial fibrillation. | Atrial fibrillation (AF) is associated with cardiac fibrosis, which can now be measured noninvasively using T1-mapping with cardiac magnetic resonance imaging (CMRI). This study aimed to assess the impact of AF on ventricular T1 at the time of CMRI.</AbstractText>Subjects with AF scheduled for AF ablation underwent CMRI with standard electrocardiography gating and breath-hold protocols on a 1.5 T scanner with post-contrast ventricular T1 recorded from 6 regions of interest at the mid-ventricle. Baseline demographic, clinical, and imaging characteristics were examined using univariate and multivariable linear regression modeling for an association with myocardial T1.</AbstractText>One hundred fifty-seven patients were studied (32% women; median age, 61 years [interquartile range {IQR}, 55-67], 50% persistent AF [episodes>7 days or requiring electrical or pharmacologic cardioversion], 30% in AF at the time of the CMRI). The median global T1 was 404 ms (IQR, 381-428). AF at the time of CMRI was associated with a 4.4% shorter T1 (p=0.000) compared to sinus rhythm when adjusted for age, sex, persistent AF, body mass index, congestive heart failure, and renal dysfunction (estimated glomerular filtration rate<60). A post-hoc multivariate model adjusted for heart rate suggested that heart rate elevation (p=0.009) contributes to the reduction in T1 observed in patients with AF at the time of CMRI. No association between ventricular T1 and AF recurrence after ablation was demonstrated.</AbstractText>AF at the time of CMRI was associated with lower post-contrast ventricular T1 compared with sinus rhythm. This effect was at least partly due to elevated heart rate. T1 was not associated with the recurrence of AF after ablation.</AbstractText> |
9,981 | An inappropriate defibrillator shock during ventricular tachycardia. | Ventricular oversensing in patients with defibrillators is an infrequent but deleterious condition. We report a patient with a cardiac resynchronization-defibrillation device that presented with hyperkalemia and syncope. Device interrogation revealed ventricular double-counting within the QRS of a slow ventricular tachycardia, resulting detection of the slow ventricular tachycardia in the ventricular fibrillation zone, and delivery of an effective therapy, below device programmed detection rate. This case of defibrillator inappropriate detection emphasizes the relevance of device electrogram interrogation in order to minimize inappropriate therapies. |
9,982 | Dual chamber pacing mode in an atrial antitachycardia pacing device without a ventricular lead - A necessary evil. | We present a case of a single chamber atrial pacemaker implanted for sinus node dysfunction and treatment of macroreentrant atrial tachycardias with atrial antitachycardia pacing. The patient presented with sustained atrial tachycardia above the detection rate, however, the device was unable to detect the tachycardia and did not deliver the programmed therapy. We discuss the nuances of the atrial tachyarrhythmia detection algorithms, and the programming strategies to maximize detection of atrial arrhythmias in a single chamber atrial pacemaker. |
9,983 | Delayed AICD therapy and cardiac arrest resulting from undersensing of ventricular fibrillation in a subject with hypertrophic cardiomyopathy-A case report. | Defibrillation testing is no longer routinely performed after automatic implantable cardioverter-defibrillator (AICD) implantation. However, certain subjects undergoing AICD implantation may be at higher risk of undersensing of ventricular arrhythmias resulting in potentially fatal outcomes. We present the case of a 30-year-old woman with hypertrophic cardiomyopathy (HCM; 'asymmetric septal hypertophy' morphologic variant) and prophylactic AICD who experienced an out of hospital cardiac arrest. AICD interrogation revealed undersensing as a result of intermittent high amplitude electrograms during an episode of ventricular fibrillation (VF). The subject underwent replacement and repositioning of the AICD lead along with pulse generator replacement (that utilized a different VF sensing algorithm) with appropriate sensing of VF and successful defibrillation testing. The presence of intermittent high amplitude electrograms during episodes of VF in AICDs using the AGC function should be recognized as a situation that may necessitate interventions to prevent undersensing and consequent delay in therapy. |
9,984 | Direct His-Bundle Pacing Improved Left Ventricular Function and Remodelling in a Biventricular Pacing Nonresponder. | The optimal pacing modality after atrioventricular junction (AVJ) ablation remains unclear. Herein, we describe the case of a heart failure patient who had AVJ ablation for chronic atrial fibrillation and received a cardiac resynchronization therapy defibrillator device. Because of the lack of clinical response to biventricular pacing, the device was revised with the addition of direct His bundle pacing, which resulted in significant improvement in functional status and left ventricular indices. This case illustrated direct His bundle pacing as an alternative for conventional biventricular pacing in some cardiac resynchronization therapy nonresponders who undergo AVJ ablation for atrial fibrillation and have an intact distal conduction system. |
9,985 | Heart Transplant in Patients with Predominantly Rheumatic Valvular Heart Disease. | International records indicate that only 2.6% of patients with heart transplants have valvular heart disease. The study aim was to evaluate the epidemiological and clinical profile of patients with valvular heart disease undergoing heart transplantation.</AbstractText>Between 1985 and 2013, a total of 569 heart transplants was performed at the authors' institution. Twenty patients (13 men, seven women; mean age 39.5 +/- 15.2 years) underwent heart transplant due to structural (primary) valvular disease. Analyses were made of the patients' clinical profile, laboratory data, echocardiographic and histopathological data, and mortality and rejection.</AbstractText>Of the patients, 18 (90%) had a rheumatic etiology, with 85% having undergone previous valve surgery (45% had one or more operations), and 95% with a normal functioning valve prosthesis at the time of transplantation. Atrial fibrillation was present in seven patients (35%), while nine (45%) were in NYHA functional class IV and eight (40%) in class III. The indication for cardiac transplantation was refractory heart failure in seven patients (35%) and persistent NYHA class III/IV in ten (50%). The mean left ventricular ejection fraction (LVEF) was 26.6 +/- 7.9%. The one-year mortality was 20%. Histological examination of the recipients' hearts showed five (27.7%) to have reactivated rheumatic myocarditis without prior diagnosis at the time of transplantation. Univariate analysis showed that age, gender, LVEF, rheumatic activity and rejection were not associated with mortality at one year.</AbstractText>Among the present patient cohort, rheumatic heart disease was the leading cause of heart transplantation, and a significant proportion of these patients had reactivated myocarditis diagnosed in the histological analyses. Thus, it appears valid to investigate the existence of rheumatic activity, especially in valvular cardiomyopathy with severe systolic dysfunction before transplantation.</AbstractText> |
9,986 | Natural history of coexistent mitral regurgitation after aortic valve replacement. | The long-term evolution of coexistent mitral regurgitation (MR) after aortic valve replacement (AVR) for aortic stenosis remains poorly defined. Prior studies have demonstrated that acute improvement in MR after AVR is modest, and more aggressive approaches have been advocated. This study examines the evolution of MR after AVR and identifies prognostic indicators for MR improvement.</AbstractText>We retrospectively evaluated demographic and echocardiographic data of 423 patients who underwent primary isolated AVR for aortic stenosis with coexistent mild (n = 314) or moderate (n = 109) MR at our institution, from 2004 to 2013. For each patient, preoperative and postoperative MR was extracted from 903 echocardiograms and graded on a 0 to 4+ scale. Hierarchic linear models were used to estimate postoperative residual MR over a 5-year follow-up period. Patients were then stratified by improvement in MR, and preoperative risk factors and survival were compared between groups. Cox proportional hazards regression was used to assess the association between survival and preoperative and postoperative MR.</AbstractText>The overall acute reduction in MR was -0.23 degrees per patient. Patients with moderate MR had a -0.53 degree reduction in MR, whereas patients with mild MR had only a -0.13 degree reduction in MR (P < .001). Residual MR, however, worsened over time and regressed back to baseline, particularly in patients with preoperative moderate MR. At last follow-up, 70 (17%) patients returned to 2+ or worse MR. Residual MR at last echocardiographic follow-up was not affected by left ventricular ejection fraction, severity of preoperative aortic valve gradient (AVG), magnitude of reduction of AVG, or other comorbidities. Degree of preoperative MR did not affect midterm survival. Patients whose MR improved after AVR demonstrated a trend toward improved survival (75% vs 65% 5-year survival; P = .06), compared with those without MR whose survival remained unchanged or worsened.</AbstractText>Coexistent MR modestly improves after AVR, but eventually regresses back to baseline or worsens over time in many patients. Preoperative AVG, reduction of AVG, heart failure, or atrial fibrillation was not predictive of residual MR. Moderate preoperative MR did not adversely affect 5-year survival. Patients with improvement in MR, however, demonstrated a trend toward improved survival at 5 years. More aggressive approaches for coexistent moderate MR should be considered in patients who need AVR for aortic stenosis.</AbstractText>Copyright © 2016 The American Association for Thoracic Surgery. Published by Elsevier Inc. All rights reserved.</CopyrightInformation> |
9,987 | Practice Patterns for Outpatients With Stable Coronary Artery Disease: A Case Vignette-based Survey Among French Cardiologists. | Although medical management of patients with coronary artery disease (CAD) is often based on scientific guidelines, a number of everyday clinical situations are not specifically covered by recommendations or the level of evidence is low. The aim of this study was to assess practice patterns regarding routine management of patients with stable CAD.</AbstractText>A survey comprising six questions on two clinical scenarios regarding stable CAD management was sent to 345 cardiologists from the Nord-Pas-de-Calais Region (France). We first assessed practice patterns globally and then searched for associations with physician characteristics (age, gender, sub-specialty, and type of practice).</AbstractText>The response rate was 92%. Regarding management of asymptomatic CAD, 86% of the cardiologists performed routine exercise testing, before which, 69% withdrew β-blockers. After a positive exercise test, 26% immediately performed coronary angiography and 67%, further imaging tests. In the absence of left ventricular dysfunction or history of myocardial infarction, routine β-blocker prescription for stable CAD was selected by 43%. When anticoagulation was needed for atrial fibrillation, 41% initiated direct oral anticoagulants rather than vitamin-K antagonists and 50% combined aspirin with anticoagulants. For recurrent stable angina in patients with known CAD, 24% performed coronary angiography directly, 49% requested a stress test, and 27% opted for medical therapy without further diagnostic testing. Age, gender of the cardiologist, academic environment, and practice of interventional cardiology were associated with certain management patterns.</AbstractText>When not guided by high-level recommendations, practice patterns for routine clinical situations in stable CAD vary considerably. Future clinical trials should address these clinical interrogations.</AbstractText> |
9,988 | Effects of Shen-Fu injection on coagulation-fibrinolysis disorders in a porcine model of cardiac arrest. | The objective of the study is to investigate the effects of Shen-Fu injection (SFI) on coagulation-fibrinolysis disorders in a porcine model of cardiac arrest.</AbstractText>Thirty Wuzhishan pigs were randomly assigned into the sham operation group (SO group, n = 6), epinephrine group (EP group, n = 12), and SFI group (n = 12). After 8 minutes of untreated ventricular fibrillation (VF), pigs in the EP group or SFI group were administered with either EP (0.02 mg/kg) or SFI (1.0 mL/kg), respectively. Plasma levels of tissue factor, thrombin-antithrombin complex, tissue factor pathway inhibitor, antithrombin III, protein C, tissue plasminogen activator, plasminogen activator inhibitor 1, soluble thrombomodulin, and soluble endothelial protein C receptor were measured at baseline, 1, 6, 12, and 24 hours after return of spontaneous circulation (ROSC). In addition, arterial lactate levels were measured at baseline, 1, 6, 12, and 24 hours after ROSC, and lactate clearance was calculated at 1, 6, 12, and 24 hours after ROSC.</AbstractText>Compared with the EP group, tissue factor, thrombin-antithrombin complex, tissue factor pathway inhibitor, tissue plasminogen activator, and plasminogen activator inhibitor 1 levels were significantly lower, whereas antithrombin III and protein C levels were significantly higher in the SFI group (all P < .05). In addition, soluble thrombomodulin and soluble endothelial protein C receptor levels in the SFI group were significantly lower in comparison to the EP group (all P < .01). Furthermore, arterial lactate levels were significantly lower, and lactate clearance was higher in the SFI group (all P < .01).</AbstractText>This study demonstrates that SFI can inhibit coagulation-fibrinolysis disorders after cardiac arrest, which may be associated with alleviating endothelial damage and improving systemic metabolism.</AbstractText>Copyright © 2015 Elsevier Inc. All rights reserved.</CopyrightInformation> |
9,989 | Blunted rate-dependent left atrial pressure response during isoproterenol infusion in atrial fibrillation patients with impaired left ventricular diastolic function: a comparison to pacing. | A heart rate (HR)-dependent haemodynamic linkage between peak left atrial (LA) pressure during sinus rhythm (LAPpeak) and estimated left ventricular (LV) filling pressure (E/Em) has not yet been explored. We hypothesized that rate-dependent LAPpeak response differs depending on E/Em in patients with atrial fibrillation (AF).</AbstractText>A total of 331 patients (68.0% male, 59.8 ± 10.8 years old) undergoing radiofrequency catheter ablation (RFCA) for AF were included, and their LAPpeak in sinus rhythm was recorded at the beginning of the procedure and at the HRs of 90, 100, 110, and 120 b.p.m. during right atrial pacing and isoproterenol (ISO-stress) infusion. We compared LAPpeak changes between patients with E/Em ≥ 15 (n = 58) and those with <15 (n = 273). (i) The patterns of pacing rate-dependent LAPpeak increase were similar in both the E/Em < 15 (P < 0.001) and E/Em ≥ 15 groups (P = 0.002). (ii) The ISO-stress reduced LAPpeak in patients with E/Em < 15 (P = 0.015), but not in those with E/Em ≥ 15 (P = 0.582). (iii) Paradoxical ISO-stress LAP elevation in patients with E/Em ≥ 15 was independently associated with 1-year follow-up E/Em reduction (B = -4.07, 95% CI -5.41 to -2.72, P < 0.001). Coexistence of E/Em ≥ 15 and ISO-stress LAP elevation increased specificity in predicting 1-year follow-up E/Em reduction after AF ablation than E/Em alone.</AbstractText>Isoproterenol LAPpeak reduction was blunted in patients with impaired LV diastolic function estimated by E/Em ≥ 15. The improvement of LV diastolic dysfunction 1 year after AF ablation was independently associated with both paradoxical ISO-stress LAP elevation and E/Em ≥ 15 at the time of procedure.</AbstractText>NCT02138695.</AbstractText>Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2015. For permissions please email: journals.permissions@oup.com.</CopyrightInformation> |
9,990 | The role of variability in night-time mean heart rate on the prediction of ventricular arrhythmias and all-cause mortality in implantable cardioverter defibrillator patients. | This study was to use implantable cardioverter defibrillator (ICD) home monitoring (HM) feature to evaluate the role of mean night-time heart rate (MNHR) in the occurrence of ventricular arrhythmias (VAs) and mortality.</AbstractText>This study retrospectively analysed clinical and ICD device data in 318 ICD patients. Data of the first 30-day MNHR (recorded 02:00-06:00 am) by HM were collected. The average and standard deviation of 30-day MNHR (AVHR and SDHR, respectively) were then determined in each patient. The primary endpoint was appropriate ICD treatment of VAs. The secondary endpoint was all-cause mortality. During a mean follow-up period of 32 ± 10 months, 179 of the 318 patients (56.3%) experienced VAs, 123 patients (38.7%) were treated by ICD shocks, and 37 patients (11.6%) died. The overall SDHR in this study cohort was 4.5 ± 3.0 bpm. Based on the receiver operating characteristic curve, the cut-off value of SDHR = 3.685 bpm was identified to predict VAs. In the Kaplan-Meier survival, SDHR ≥ 3.685 bpm was associated with increased VAs [hazard ratio (HR) = 1.885; 95% confidence interval (CI) = 1.362-2.609; P < 0.001], shock events (HR = 1.637; 95% CI = 1.11-2.414; P = 0.013), all-cause mortality (HR = 2.42; 95% CI = 1.266-4.627; P = 0.008), and the combined endpoints (HR = 1.872; 95% CI = 1.365-2.567; P < 0.001). In univariate and multivariate Cox models (adjusting for clinical factors), SDHR ≥ 3.685 bpm was still an independent predictor for all endpoints.</AbstractText>In ICD population, SDHR ≥ 3.685 bpm was an independent predictor for VAs and all-cause mortality.</AbstractText>Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2015. For permissions please email: journals.permissions@oup.com.</CopyrightInformation> |
9,991 | First clinical experience of the safety and feasibility of total subcutaneous implantable defibrillator in an Asian population. | The safety and feasibility of a subcutaneous implantable cardioverter-defibrillator (S-ICD) has been demonstrated in the treatment of life-threatening ventricular tachyarrhythmias (VT). Nonetheless, its safety and feasibility in an Asian population with smaller body-build is unclear.</AbstractText>Twenty-one Asian patients who underwent S-ICD from 1 April 2014 to 2 February 2015 in five institutions in Hong Kong and Singapore were retrospectively reviewed. Twenty-one patients with a mean age of 50.0 ± 14.1 years (range 29-77 years, 82.6% male) were included. Among them, 17 (81.0%) were Chinese, 3 (14.3%) were Malay, and 1 (4.8%) was Indian. Their mean body mass index was 23.0 ± 4.0 kg/m(2). An S-ICD was implanted for primary and secondary prevention in 13 (61.9%) and 8 (38.1%) patients, respectively. The indications included Brugada syndrome (n = 6, 28.6%), ischaemic cardiomyopathy (CMP, n = 6, 28.6%), dilated CMP (n = 4, 19.0%), hypertrophic CMP (n = 2, 9.5%), and idiopathic ventricular fibrillation (n = 2, 9.5%). Three patients (14.3%) had prior infected transvenous ICD. There were no acute complications but eight wound complications (persistent wound bleeding requiring intervention = 2; delayed wound healing: upper sternal wound = 3; generator site = 1; local wound infection = 2) were observed in six (28.2%) patients. After a mean follow-up of 107.2 ± 81.3 days (range of 14-254 days), one patient underwent three successful appropriate shocks for treatment of VTs. No inappropriate therapy was documented.</AbstractText>Our initial experience shows that S-ICD is a feasible treatment for VT among an Asian population with smaller body-build. There was nonetheless a relatively high rate of wound complications.</AbstractText>Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2015. For permissions please email: journals.permissions@oup.com.</CopyrightInformation> |
9,992 | Sudden cardiac death in China: current status and future perspectives. | Sudden cardiac death (SCD) is a major cause of mortality worldwide. Similar to the number of SCDs in western countries including the USA, the number of SCDs in China is ∼544,000 annually. However, there are significant differences in patient characteristics between Chinese primary prevention population and U.S. primary prevention population. In contrast to western countries where implantable cardioverter-defibrillator (ICD) devices have been well adopted as a major effective method for both primary and secondary prevention of SCD, China has a low prevalence of ICD utilization (∼1.5 device per 1 million people). Socioeconomic and political factors, awareness and knowledge of SCD, and the difference in disease patterns have led to the underutilization of ICD in China. China, as the most populated and the second largest economic country in the world, has now taken variable approaches to address this pressing health problem and enhances the delivery of lifesaving therapies, including arrhythmia ablation and medical treatment besides ICD, to patients who are at risk of SCD. |
9,993 | Electrical Injury-Induced Complete Atrioventricular Block: Is Permanent Pacemaker Required? | A considerable percentage of electrical injuries occur as a result of work activities. Electrical injury can lead to various cardiovascular disorders: acute myocardial necrosis, myocardial ischemia, heart failure, arrhythmias, hemorrhagic pericarditis, acute hypertension with peripheral vasospasm, and anomalous, nonspecific ECG alterations. Ventricular fibrillation is the most common arrhythmia resulting from electrical injury and is the leading cause of death in electrical (especially low voltage alternating current) injury cases. Asystole, premature ventricular contractions, ventricular tachycardia, conduction disorders (various degrees of heart blocks, bundle-brunch blocks), supraventricular tachycardia, and atrial fibrillation are the other arrhythmic complications of electrical injury. Complete atrioventricular block has rarely been reported and permanent pacemaker was required for the treatment in some of these cases. Herein, we present a case of reversible complete atrioventricular block due to low voltage electrical injury in a young electrical technician. |
9,994 | Early Repolarisation - What Should the Clinician Do? | The early repolarisation (ER) pattern is a common ECG finding. Most individuals with the ER pattern are at minimal risk for arrhythmic events. In others, ER increases the arrhythmic risk of underlying cardiac pathology. Rarely ER syndrome will manifest as a primary arrhythmogenic disorder causing ventricular fibrillation (VF). ER syndrome is defined as syncope attributed to ventricular arrhythmias or cardiac arrest attributed to ER following systematic exclusion of other etiologies. Some ECG features associated with ER portend a higher risk. However, clinically useful risk-stratifying tools to identify the asymptomatic patient at high risk are lacking. Patients with asymptomatic ER and no family history of malignant ER should be reassured. All patients with ER should continue to have modifiable cardiac risk factors addressed. Symptomatic patients should be systematically investigated, directed by symptoms. |
9,995 | Contemporary Mapping Techniques of Complex Cardiac Arrhythmias - Identifying and Modifying the Arrhythmogenic Substrate. | Cardiac electrophysiology has moved a long way forward during recent decades in the comprehension and treatment of complex cardiac arrhythmias. Contemporary electroanatomical mapping systems, along with state-of-the-art technology in the manufacture of electrophysiology catheters and cardiac imaging modalities, have significantly enriched our armamentarium, enabling the implementation of various mapping strategies and techniques in electrophysiology procedures. Beyond conventional mapping strategies, ablation of complex fractionated electrograms and rotor ablation in atrial fibrillation ablation procedures, the identification and modification of the underlying arrhythmogenic substrate has emerged as a strategy that leads to improved outcomes. Arrhythmogenic substrate modification also has a major role in ventricular tachycardia ablation procedures. Optimisation of contact between tissue and catheter and image integration are a further step forward to augment our precision and effectiveness. Hybridisation of existing technologies with a reasonable cost should be our goal over the next few years. |
9,996 | Long-Term Prognostic Role of the Diagnostic Criteria for Arrhythmogenic Right Ventricular Cardiomyopathy/Dysplasia. | The aim of this study was to evaluate the long-term prognostic role of the 2010 task force criteria (TFC)-based scoring in patients with arrhythmogenic right ventricular cardiomyopathy/dysplasia (ARVC/D).</AbstractText>Categories of the 2010 TFC include the risk factors for cardiovascular mortality and sudden cardiac death in patients with ARVC/D.</AbstractText>Ninety patients with ARVC/D who met the definitive diagnosis of the 2010 TFC were retrospectively studied. ARVC/D risk score was calculated as the sum of major (2 points) and minor (1 point) criteria in all 6 subdivided categories of the TFC and was divided into tertile groups of scores; group A (4 to 6 points), group B (7 to 9 points), and group C (10 to 12 points). The primary endpoints were major adverse cardiovascular events: cardiovascular death, heart failure hospitalization, and sustained ventricular tachycardia or ventricular fibrillation.</AbstractText>During the follow-up period of 10.2 ± 7.1 years, 19 patients died because of cardiovascular causes, 28 patients were admitted because of worsened heart failure, and 47 patients experienced sustained ventricular tachycardia or ventricular fibrillation. Patients in groups B and C were at increased risk for major adverse cardiovascular events compared with those in group A (hazard ratio [HR]: 4.80; 95% confidence interval [CI]: 1.87 to 12.33; p = 0.001; and HR: 6.15; 95% CI: 2.20 to 17.21; p = 0.001, respectively). Patients in groups B and C were at increased risk for sustained ventricular tachycardia or ventricular fibrillation compared with those in group A (HR: 6.64; 95% CI: 2.00 to 22.03; p = 0.002; and HR: 9.18; 95% CI: 2.60 to 32.40; p = 0.001, respectively).</AbstractText>Our study suggests that risk scoring based on the 2010 TFC is useful to predict major adverse cardiovascular events in patients with ARVC/D.</AbstractText>Copyright © 2016 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.</CopyrightInformation> |
9,997 | [Hypertrophic cardiomyopathy with midventricular obstruction of the left ventricle (MVO)--case report]. | A 76-year old woman with a history of stage 3 arterial hypertension, paroxysmal atrial fibrillation, hypercholesterolemia and type 2 diabetes mellitus. Ventricular tachycardia was the first clinical manifestation of the disease. Echocardiography revealed hypertrophic cardiomyopathy with a high intraventricular gradient of 47 mmHg and midventricular obstruction at the level of the papillary muscles (the lumen of the left ventricle was 1-2 mm during systole). No ventricular aneurysm was found but the ventricle was elongated and dilated in the periapical part where systolic function was decreased but synchronized in time. Coronary angiograms showed no narrowing of coronary arteries. A single-chamber cardioverter-defibrillator (ICD, implantable cardioverter-defibrillator) was implanted to prevent sudden cardiac death. Modified-release metoprolol and amiodarone were administered in antiarrhythmic therapy. This case represents a rare kind of hypertrophic cardiomyopathy in an elderly woman which is characterized by midventricular obstruction. |
9,998 | [Occurrence and clinical characteristics of sleep apnea syndrome in heart failure patients with atrial fibrillation]. | To evaluate the occurrence and clinical characteristics of sleep apnea syndrome (SAS) in heart failure (HF) patients with atrial fibrillation (AF).</AbstractText>From HF patients hospitalized in the First Affiliated Hospital of Nanjing Medical University during June 2012 and June 2014, subjects were recruited based on electrocardiography examination, including 110 patients with AF (coexisting AF group) and 105 parallel control patients without AF but with matched age, gender and body mass index (simple HF group). Comparison was made about the occurrence and characteristics of SAS between two groups.</AbstractText>There was no statistical difference in causes of HF, complications, New York Heart Association class and basic medication between two groups. Compared with the patients in simple HF group, the patients in coexisting AF group had a significantly higher Epworth sleepiness scale score, larger cardiothoracic ratio (10.1±5.8 vs 8.2±5.5, 0.63±0.08 vs 0.57±0.07; both P<0.05), and shorter 6-minute walk distance [(305±70) vs (335±69) m, P<0.05]. There was no difference in left ventricular ejection fraction, left ventricular end-diastolic dimension and left ventricular end-systolic dimension between two groups. However, left atrial diameter was remarkably larger in coexisting AF group than that in simple HF group (P<0.05). The prevalence of SAS was higher in coexisting AF group than that in simple HF group (36.4% vs 20.0%, P<0.05). Compared with simple HF group, the coexisting AF group had a higher apnea/hypopnea index [4(1, 16) vs 3(1, 7) times/h, P<0.05]. No significant differences were detected between two groups among the rapid of eye movement sleep stage/total sleep time, arousal index, mean and lowest pulse oxygen saturation (SpO2) and oxygen desaturation index.</AbstractText>HF patients with AF have a higher frequency of SAS, more severe daytime sleepiness and poorer physical activity than matched simple HF patients without AF.</AbstractText> |
9,999 | Epidemiology of Out-of-Hospital Cardiac Arrests Among Japanese Centenarians: 2005 to 2013. | Although the number of centenarians has been rapidly increasing in industrialized countries, no clinical studies evaluated their characteristics and outcomes from out-of-hospital cardiac arrests (OHCAs). This nationwide, population-based, observation of the whole population of Japan enrolled consecutive OHCA centenarians with resuscitation attempts before emergency medical service arrival from 2005 to 2013. The primary outcome measure was 1-month survival from OHCAs. The multivariate logistic regression model was used to assess factors associated with 1-month survival in this population. Among a total of 4,937 OHCA centenarians before emergency medical service arrival, the numbers of those with OHCAs increased from 70 in 2005 to 136 in 2013 in men and from 227 in 2005 to 587 in 2013 in women. Women accounted for 80.3%. Ventricular fibrillation (VF) as first documented rhythm was 2.5%. The proportions of victims receiving bystander cardiopulmonary resuscitation were 64.2%. The proportion of 1-month survival from OHCAs in centenarians was only 1.1%. In a multivariate analysis, age was not associated with 1-month survival from OHCAs (adjusted odds ratio [OR] for one increment of age 1.01; 95% confidence interval [CI] 0.87 to 1.18). Witness by a bystander (adjusted OR 3.45; 95% CI 1.88 to 6.31) and VF as first documented rhythm (adjusted OR 5.49; 95% CI 2.24 to 13.43) were significant positive predictors for 1-month survival. Cardiac origin was significantly poor in 1-month survival compared with noncardiac origin (adjusted OR 0.37; 95% CI 0.21 to 0.64). In conclusion, survival from OHCAs in centenarians was very poor, but witness by a bystander and VF as first documented rhythm were associated with improved survival. |
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