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14,100
Heart failure epicardial fat increases atrial arrhythmogenesis.
Obesity is an important risk factor for atrial fibrillation (AF) and heart failure (HF). The effects of epicardial fat on atrial electrophysiology were not clear. This study was to evaluate whether HF may modulate the effects of epicardial fat on atrial electrophysiology.</AbstractText>Conventional microelectrodes recording was used to record the action potential in left (LA) and right (RA) atria of healthy (control) rabbits before and after application of epicardial fat from control or HF (ventricular pacing of 360-400 bpm for 4 weeks) rabbits. Adipokine profiles were checked in epicardial fat of control and HF rabbits.</AbstractText>The LA 90% of AP duration was prolonged by control epicardial fat (from 77 &#xb1; 6 to 87 &#xb1; 7 ms, p&lt;0.05, n=7), and by HF epicardial fat (from 78 &#xb1; 3 to 98 &#xb1; 4 ms, p&lt;0.001, n=9). However, control or HF epicardial fat did not change the AP morphology in RA. HF epicardial fat increased the contractility in LA (61 &#xb1; 11 vs. 35 &#xb1; 6 mg, p=0.001), but not in RA. Control fat did not change the LA or RA contractility. Moreover, control and HF epicardial fat induced early and delayed afterdepolarizations in LA and RA, but only HF epicardial fat provoked spontaneous activity and burst firing in LA (n=3/9, 33.3% vs. n=0/7, 0%, n=0/9, 0%, p&lt;0.05). Compared to control fat, HF epicardial fat, had lower resistin, C-reactive protein and serum amyloid A, but similar interleukin-6, leptin, monocyte chemotactic protein-1, adiponectin and adipsin.</AbstractText>HF epicardial fat increases atrial arrhythmogenesis, which may contribute to the higher atrial arrhythmia in obesity.</AbstractText>Copyright &#xa9; 2012 Elsevier Ireland Ltd. All rights reserved.</CopyrightInformation>
14,101
Aggressive cardiovascular phenotype of aneurysms-osteoarthritis syndrome caused by pathogenic SMAD3 variants.
The purpose of this study was describe the cardiovascular phenotype of the aneurysms-osteoarthritis syndrome (AOS) and to provide clinical recommendations.</AbstractText>AOS, caused by pathogenic SMAD3 variants, is a recently described autosomal dominant syndrome characterized by aneurysms and arterial tortuosity in combination with osteoarthritis.</AbstractText>AOS patients in participating centers underwent extensive cardiovascular evaluation, including imaging, arterial stiffness measurements, and biochemical studies.</AbstractText>We included 44 AOS patients from 7 families with pathogenic SMAD3 variants (mean age: 42 &#xb1; 17 years). In 71%, an aortic root aneurysm was found. In 33%, aneurysms in other arteries in the thorax and abdomen were diagnosed, and in 48%, arterial tortuosity was diagnosed. In 16 patients, cerebrovascular imaging was performed, and cerebrovascular abnormalities were detected in 56% of them. Fifteen deaths occurred at a mean age of 54 &#xb1; 15 years. The main cause of death was aortic dissection (9 of 15; 60%), which occurred at mildly increased aortic diameters (range: 40 to 63 mm). Furthermore, cardiac abnormalities were diagnosed, such as congenital heart defects (6%), mitral valve abnormalities (51%), left ventricular hypertrophy (19%), and atrial fibrillation (22%). N-terminal brain natriuretic peptide (NT-proBNP) was significantly higher in AOS patients compared with matched controls (p &lt; 0.001). Aortic pulse wave velocity was high-normal (9.2 &#xb1; 2.2 m/s), indicating increased aortic stiffness, which strongly correlated with NT-proBNP (r = 0.731, p = 0.005).</AbstractText>AOS predisposes patients to aggressive and widespread cardiovascular disease and is associated with high mortality. Dissections can occur at relatively mildly increased aortic diameters; therefore, early elective repair of the ascending aorta should be considered. Moreover, cerebrovascular abnormalities were encountered in most patients.</AbstractText>Copyright &#xa9; 2012 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.</CopyrightInformation>
14,102
Circulating matrix metalloproteinases in adolescents with hypertrophic cardiomyopathy and ventricular arrhythmia.
Myocardial fibrosis is a hallmark of hypertrophic cardiomyopathy (HCM) and a risk factor for ventricular arrhythmia. Fibrosis can be reflected in circulating matrix remodeling protein concentrations. We explored differences in circulating markers of extracellular matrix turnover between young HCM patients with versus without history of serious arrhythmia.</AbstractText>Using multiplexed and single ELISA, matrix metalloproteinases (MMPs) 1, 2, 3, and 9; tissue inhibitor of metalloproteinases (TIMPs) 1, 2, and 4; and collagen I carboxyterminal peptide (CICP) were measured in plasma from 45 young HCM patients (80% male patients; median age, 17 years [interquartile range, 15-20]). Participants were grouped into serious ventricular arrhythmia history (VA) versus no ventricular arrhythmia history (NoVA). Differences in MMPs between groups were examined nonparametrically. Relationships between MMPs and ventricular arrhythmia were assessed with linear regression, adjusted for interventricular septal thickness, family history of sudden death, abnormal exercise blood pressure, and implantable cardioverter-defibrillator (ICD). In post hoc sensitivity analysis, age was substituted for ICD. The 14 VA patients were older than 31 NoVA patients (median, 19 versus 17 years; P=0.03). All 14 VA and 12 NoVA patients had an ICD. MMP3 concentration was significantly higher in the VA group (VA median, 12.9 &#x3bc;g/mL [interquartile range, 5.7-16.7 &#x3bc;g/mL] versus NoVA, 5.8 &#x3bc;g/mL [interquartile range, 3.7-10.0 &#x3bc;g/mL]; P=0.01). On multivariable analysis, VA was independently associated with increasing MMP3 (standardized &#x3b2;, 0.37; P=0.01). Post hoc adjustment for age attenuated this association.</AbstractText>Circulating MMP3 may be a marker of ventricular arrhythmia in adolescent patients with HCM. Because of our role as pediatric providers, we cannot exclude age-related confounding.</AbstractText>
14,103
Dynamicity of the J-wave in idiopathic ventricular fibrillation with a special reference to pause-dependent augmentation of the J-wave.
This study evaluated the pause-dependency of the J-wave to characterize this phenomenon in idiopathic ventricular fibrillation (VF).</AbstractText>The J-wave can be found in apparently healthy subjects and in patients at risk for sudden cardiac death, and risk stratification is therefore needed.</AbstractText>Forty patients with J-wave-associated idiopathic VF were studied for J waves with special reference concerning pause-dependent augmentation. J waves were defined as those &#x2265;0.1 mV above the isoelectric line and were compared with 76 non-VF patients of comparable age and sex.</AbstractText>The J-wave was larger in patients with idiopathic VF than in the controls: 0.360 &#xb1; 0.181 mV versus 0.192 &#xb1; 0.064 mV (p = 0.0011). J waves were augmented during storms of VF (n = 9 [22.5%]), which was controlled by isoproterenol; they disappeared within weeks in 5 patients. In addition, sudden prolongation of the R-R interval was observed in 27 patients induced by benign arrhythmia, and 15 patients (55.6%) demonstrated pause-dependent augmentation (from 0.391 &#xb1; 0.126 mV to 0.549 &#xb1; 0.220 mV; p &lt; 0.0001). In the other 12 experimental subjects and in the 76 control subjects, J waves remained unchanged. Pause-dependent augmentation of J waves was detected in 55.6% (sensitivity) but was specific (100%) in the patients with idiopathic VF with high positive (100%) and negative (86.4%) predictive values.</AbstractText>Pause-dependent augmentation of J waves was confirmed in about one-half of the patients with idiopathic VF after sudden R-R prolongation. Such dynamicity of J waves was specific to idiopathic VF and may be used for risk stratification.</AbstractText>Copyright &#xa9; 2012 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.</CopyrightInformation>
14,104
Rocuronium and sugammadex used effectively for electroconvulsive therapy in a patient with Brugada syndrome.
We report the successful anesthetic management of a patient with Brugada syndrome who underwent electroconvulsive therapy to treat bipolar disorder. Suxamethonium and neostigmine were contraindicated to avoid the vagotonic effects that can precipitate ventricular fibrillation during anesthesia in patients with Brugada syndrome. The combination of 1.2 mg/kg rocuronium and 10 mg/kg sugammadex was effectively and safely used to induce and antagonize neuromuscular block for 8 consecutive electroconvulsive therapy sessions in this patient.
14,105
Two distinct electrocardiographic forms of idiopathic ventricular arrhythmia originating in the vicinity of the His bundle.
The objective is to assess electrocardiographic characteristics predicting the precise location of ventricular arrhythmia (VA) origin within the right ventricle (RV) close to the His bundle (HB) region.</AbstractText>Twenty-five patients (14 men, age 65 &#xb1; 14 years) underwent successful catheter ablation of para-Hisian VA. Ventricular arrhythmias were considered to arise in the vicinity of the HB region based on the criteria that mapping exhibited the earliest RV activation before QRS onset in the HB region. Surface 12-lead electrocardiogram during the para-Hisian VAs was analysed. Of the 25 patients, 8 originated from the RV antero-septum just above the HB region, and 17 arose from the RV mid-septum just below the HB region. There was no significant difference in precedence of the local ventricular electrogram of the HB region from the onset of surface QRS during VAs. Surface electrocardiographic findings were characterized according to R-wave amplitude in lead I (0.43 &#xb1; 0.18 vs. 0.67 &#xb1; 0.19 mV, P = 0.005), mean R-wave amplitude in inferior leads (1.12 &#xb1; 0.32 vs. 0.71 &#xb1; 0.24 mV, P = 0.002), R-wave amplitude ratio of leads III/II (0.77 &#xb1; 0.10 vs. 0.50 &#xb1; 0.23, P = 0.005), incidence of S-wave in lead III [1/8 (13%) vs. 16/17 (94%), P &lt; 0.001], and QS morphology in lead V1 [3/8 (38%) vs. 17/17 (100%), P = 0.001].</AbstractText>Despite their adjacent locations, para-Hisian VAs could be classified into two subgroups with distinctive electrocardiographic characteristics according to origin either above or below the HB region. The present findings can be helpful for planning catheter ablation of para-Hisian VAs, and can reduce the risk of inadvertent atrioventricular block.</AbstractText>
14,106
[Does a woman's heart beat faster?].
Recent publications have identified a different epidemiological prevalence related to sex in some of the most common supraventricular and ventricular arrhythmias. This fact is attributed to the effect of sex hormones on myocardial cell electrophysiology. Women, in particular, have a higher prevalence than males with regard to intranodal reentrant tachycardia, idiopathic monomorphic ventricular tachycardia and ventricular arrhythmias in congenital or acquired long QT syndrome. A higher incidence in females with regard to complications during atrial fibrillation has also been reported. This paper examines data from the literature regarding gender differences in the prevalence of the most common arrhythmias, the causes of these differences, and some discriminating aspects related to female sex in the architecture of published clinical studies.
14,107
Impact of preoperative atrial fibrillation on mortality and cardiovascular outcomes of mechanical mitral valve replacement for rheumatic mitral valve disease.
The prognostic significance of preoperative atrial fibrillation on mitral valve replacement remains unclear. The aim of this study was to explore the effects of the presence of preoperative atrial fibrillation on mortality and cardiovascular outcomes of mitral valve replacement for rheumatic valve disease.</AbstractText>A retrospective analysis was performed on a total of 793 patients who underwent mitral valve replacement with or without tricuspid valve repair in our hospital. The patients selected were divided into two groups according to preoperative rhythm status. Patients with preoperative atrial fibrillation were assigned to the AF group, while patients in preoperative sinus rhythm were assigned to the SR group. Postoperative follow-up was performed by outpatient visits, as well as by telephone and written correspondence. Data gathered included survivorship, postoperative complications, left ventricular function and tricuspid regurgitation.</AbstractText>For patients with atrial fibrillation vs those in sinus rhythm, there was no difference in postoperative mortality and morbidity. Follow-up was a mean of 8.6 &#xb1; 2.4 years. For patients with preoperative atrial fibrillation, 10-year survival from a Kaplan-Meier curve was 88.7%, compared with 96.6% in patients with preoperative sinus rhythm (P = 0.002). Multivariate analysis identified low left ventricular ejection fraction, older age, large left atrium and preoperative atrial fibrillation as significant adverse predictors for overall survival. Freedom from thromboembolism complications at 13 years was lower for patients with preoperative atrial fibrillation without maze procedure and left atrial appendage ligation, compared with that for patients with preoperative sinus rhythm without maze procedure and left atrial appendage ligation, and patients with concomitant maze procedure and left atrial appendage ligation (76.3 vs 94.8 vs 94.0%, respectively; P = 0.001). On echocardiography, the proportion of patients with significant tricuspid regurgitation was 38.7% (atrial fibrillation patients) vs 25.4% (patients in sinus rhythm; P &lt; 0.001). Left ventricular ejection fraction measured 5 years after surgery increased by an average of 1.2% in the AF group, while it increased by 5.3% in the SR group (P = 0.028).</AbstractText>Preoperative atrial fibrillation is a risk factor for long-term mortality, thromboembolism complications and tricuspid regurgitation, and it also has an adverse effect on the degree of improvement when considering left ventricular function.</AbstractText>
14,108
Successful surgical removal of an entrapped intravascular ultrasonography catheter in the left circumflex coronary artery.
Entrapment of an intravascular ultrasonography (IVUS) catheter is an infrequent but serious complication associated with percutaneous coronary intervention (PCI). A 67-year-old man who presented with exertional chest pain had an angiographic finding of 99 % stenosis of left circumflex coronary artery. PCI with stent implantation was performed successfully with an assessment by IVUS showing adequate stent expansion and apposition. When the IVUS catheter was retracted, it became trapped at the stent strut. The stent was deformed and the IVUS catheter became stuck there. Ventricular fibrillation suddenly occurred with deterioration of the coronary flow. He was transferred to the operating room just after insertion of intra-aortic balloon pumping. The IVUS catheter, the guidewire, and the deformed stent were all removed under cardiopulmonary bypass. Coronary artery bypass graft with a saphenous vein was also performed at the more distal segment from the entrapment site. The postoperative course was uneventful with no graft occlusion.
14,109
Recrudescent digoxin toxicity treated with plasma exchange: a case report and review of literature.
A 53-year-old woman presented with digitalis toxicity caused by acute overdose that manifested as atrial tachycardia with block, sinus pauses, and competing AV junctional rhythm with atrial fibrillation. Patient admitted to overdosing with digoxin 15-20 h before presentation with intent to commit suicide. Serum digoxin level was 35.6 ng/ml and renal function was normal. Patient was treated with 1,040 mg of digoxin-specific antibody Fab fragment with prompt resolution of arrhythmias and restoration of sinus rhythm. Four hours after digoxin antibody administration, serum digoxin level declined to 0.2 ng/ml. Eighteen hours after treatment with Fab fragment, patient developed premature ventricular complexes, atrial tachycardia with and without atrioventricular block, and non-sustained ventricular tachycardia followed by ventricular fibrillation from which she was successfully resuscitated. Electrocardiogram showed no evidence of acute myocardial infarction, and emergent coronary angiogram did not reveal significant coronary artery disease. Repeat digoxin level was 20.4 ng/ml. A diagnosis of recrudescent digoxin toxicity was made and the patient was treated with one session of plasma exchange with resolution of arrhythmias. Immediately after plasma exchange, digoxin level decreased to 10.4 ng/ml, and after 10 h, the level further decreased to 6.6 ng/ml. The following day, digoxin level had decreased to 2.9 ng/ml. Our experience with this case would suggest that plasma exchange should be considered as a treatment modality for recrudescent digoxin toxicity.
14,110
Is it worth placing ventricular pacing wires in all patients post-coronary artery bypass grafting?
A best evidence topic in cardiac surgery was written according to a structured protocol. The question addressed was whether ventricular pacing wires should be placed routinely in all patients undergoing coronary artery bypass grafting (CABG) regardless of immediate post-cardiopulmonary bypass (CPB) rhythm status. Using the reported search, 142 papers were found, from which 10 papers represented the best evidence on the subject. The author, date and country of 10 publications, study type, patient group studied, relevant outcomes and results are tabulated. Complete atrio-ventricular (AV) block is the main reason for inserting ventricular pacing wires upon conclusion of CABG. Eight studies found complete AV block to be a rare entity post-CABG. The rate of complete AV block in CABG in our review ranged from 0.3 to 24%. The calculated average rate of AV block in all studies was 2.4%. The number needed to treat with ventricular wires to support a patient who develops AV block is 42. One randomized controlled trial found 3% risk of complete AV block post-CABG. Another cohort of 222 patients revealed a rate of 1.8% for complete AV block. For one cohort of 770 patients, post-CABG the rate of complete AV block was found to be 0.3%. In one cohort of 25 patients, there was a rate of 4% for complete AV block post-CABG. Another study of 564 patients revealed a rate of 0.7% for complete AV block. A study of 4999 patients post-CABG reported a rate of 1.2% for complete AV block. In one cohort of 93 patients, there was a 4% risk of complete AV block. Another cohort of 62 patients showed a rate of 1.6% for complete AV block. Only two papers found the rate of complete AV block post-CABG to be as high as 24 and 16%. Both studies were limited by sample size. In conclusion, routine ventricular pacing wire insertion post-CABG is unnecessary given that routine use of ventricular wires can occasionally cause complications such as bleeding and cardiac tamponade and thus is not risk free. We also found that the incidence of complete AV block is probably higher in on-CPB CABG than off-CPB CABG and that AV pacing may be haemodynamically beneficial for some patients postoperatively.
14,111
[Systolic and diastolic intraventricular asynchrony of the left ventricular myocardium in patients with pacemaker].
To study intraventricular asynchrony and effects of pacemaker implantation on asynchrony severity in patients with rhythm and conduction disorders.</AbstractText>The study of 46 patients with cardiac arrhythmia (atrial fibrillation, sick sinus syndrome, AB-block of the third degree) included such examinations as echocardiography, tissue dopplerography (PWTDI) before pacemaker implantation and 7 days after it. Electromechanic systolic and diastolic myocardial asynchrony was assessed by intraventricular heterogeneity index (IHb, IHm, TSD) in 8 segments of the left ventricle (LV) at the basal and mean levels. Values obtained in examination of 32 healthy volunteers were considered normal.</AbstractText>Parameters of systolic and diastolic asynchrony in patients with cardiac arrhythmia significantly differ from normal ones. Basal LV diastolic asynchrony was detected in 41-48% patients, systolic one--in 62-100%, systolodiastolic--in 41% cases. Pacemaker implantation into the right heart significantly reduces LV systolic asynchrony while diastolic one was unaffected in an early postoperative period. The best sensitivity in detection of systolic asynchrony is achieved with TsSD index. Informative value of diastolic asynchrony parameters is much less than of the systolic one.</AbstractText>Indices of systolic asynchrony (TsSD, IhbS, IhmS) can be used for heart condition control after pacemaker implantation.</AbstractText>
14,112
Improvement of P-wave dispersion is associated with a lower incidence of atrial fibrillation after cardiac resynchronization therapy.
P-wave dispersion (PWD) is a useful predictor of paroxysmal atrial fibrillation (AF). The effect of cardiac resynchronization therapy (CRT) on PWD and the prognostic implications of the improvement in PWD remain undefined. The aim of the study was to explore the clinical significance of the improvement of PWD after CRT.</AbstractText>Electrocardiographic studies were performed before and three months after CRT in 81 patients (57 men and 24 women; age (60.5 &#xb1; 11.2) years) with standard CRT indication but no history of AF. A significant improvement of PWD (PWD responder) was defined as a relative decrease &#x2265; 20% from baseline PWD. The primary endpoints were new-onset AF detected by electrocardiogram (ECG) or CRT.</AbstractText>After (30.6 &#xb1; 7.5) months of follow-up, PWD responders (n = 43) had a significantly lower incidence of AF than did PWD nonresponders, 12% vs. 29% (P &lt; 0.001). In Cox proportional hazard analysis, PWD responders was the only predictor of lower risk of new-onset AF (HR 0.33, 95% confidence interval 0.12 - 0.96, P = 0.033).</AbstractText>Improvement of P-wave dispersion after CRT was associated with a lower incidence of AF, which may be related to the significant improvement in left ventricular systolic function and the reverse modeling of the left atrium.</AbstractText>
14,113
Enhanced transmural dispersion of repolarization in patients with J wave syndromes.
Recently, great attention has been paid to the risk stratification of asymptomatic patients with an electrocardiographic early repolarization (ER) pattern. We investigated several repolarization parameters including the Tpeak-Tend interval and Tpeak-Tend/QT ratio in healthy individuals and patients with J wave syndrome who were aborted from sudden cardiac death.</AbstractText>Ninety-two subjects were enrolled: 12 patients with ventricular fibrillation associated with J waves, 40 healthy subjects with an uneventful ER pattern and 40 healthy control subjects (C) without any evident J waves. Using ambulatory electrocardiogram recordings, the average QT interval, corrected QT interval (QTc), Tpeak-Tend (Tp-e) interval, which is the interval from the peak to the end of the T wave, and Tp-e/QT ratio were calculated. Using ANOVA and post hoc analysis, there was no significant difference in the average QT and QTc in all 3 groups (QT; 396 &#xb1; 27 vs 405 &#xb1; 27 vs 403 &#xb1; 27 m, QTc; 420 &#xb1; 26 vs 421 &#xb1; 21 vs 403 &#xb1; 19 milliseconds in the C, ER pattern and J groups, respectively). The Tp-e interval and Tp-e/QT ratio were significantly more increased in the J wave group than the ER Pattern group (Tp-e: 86.7 &#xb1; 14 milliseconds vs 68 &#xb1; 13.2 milliseconds, P &lt; 0.001, Tp-e/QT; 0.209 &#xb1; 0.04 vs 0.171 &#xb1; 0.03, P &lt; 0.001), but they did not significantly differ between the C and ER pattern groups (Tp-e: 68.6 &#xb1; 7.5 vs 68 &#xb1; 13.2, P = 0.97, Tp-e/QT 0.174 &#xb1; 0.02 vs 0.171 &#xb1; 0.03, P = 0.4).</AbstractText>As novel markers of heterogeneity of ventricular repolarization, Tpeak-Tend interval and Tp-Te/QT ratio are significantly increased in patients with J wave syndromes compared to age and sex-matched uneventful ER.</AbstractText>&#xa9; 2012 Wiley Periodicals, Inc.</CopyrightInformation>
14,114
Prevalence of QT interval prolongation in patients admitted to cardiac care units and frequency of subsequent administration of QT interval-prolonging drugs: a prospective, observational study in a large urban academic medical center in the US.
Cardiac arrest due to torsades de pointes (TdP) is a rare but catastrophic event in hospitals. Patients admitted to cardiac units are at higher risk of drug-induced QT interval prolongation and TdP, due to a preponderance of risk factors. Few data exist regarding the prevalence of QT interval prolongation in patients admitted to cardiac units or the frequency of administering QT interval-prolonging drugs to patients presenting with QT interval prolongation.</AbstractText>The aim of this study was to determine the prevalence of Bazett's-corrected QT (QT(c)) interval prolongation upon admission to cardiac units and the proportion of patients presenting with QT(c) interval prolongation who are subsequently administered QT interval-prolonging drugs during hospitalization.</AbstractText>This was a prospective, observational study conducted over a 1-year period (October 2008-October 2009) in 1159 consecutive patients admitted to two cardiac units in a large urban academic medical centre located in Indianapolis, IN, USA. Patients were enrolled into the study at the time of admission to the hospital and were followed daily during hospitalization. Exclusion criteria were age &lt;18 years, ECG rhythm of complete ventricular pacing, and patient designation as 'outpatient' in a bed and/or duration of stay &lt;24 hours. Data collected included demographic information, past medical history, daily progress notes, medication administration records, laboratory data, ECGs, telemetry monitoring strips and diagnostic reports. All patients underwent continuous cardiac telemetry monitoring and/or had a baseline 12-lead ECG obtained within 4 hours of admission. QT intervals were determined manually from lead II of 12-lead ECGs or from continuous lead II telemetry monitoring strips. QT(c) interval prolongation was defined as &#x2265;470&#x2009;ms for males and &#x2265;480&#x2009;ms for females. In both males and females, QT(c) interval &gt;500&#x2009;ms was considered abnormally high. A medication was classified as QT interval-prolonging if there were published data indicating that the drug causes QT interval prolongation and/or TdP. Study endpoints were (i) prevalence of QT(c) interval prolongation upon admission to the Cardiac Medical Critical Care Unit (CMCCU) or an Advanced Heart Care Unit (AHCU); (ii) proportion of patients admitted to the CMCCU/AHCU with QT(c) interval prolongation who subsequently were administered QT interval-prolonging drugs during hospitalization; (iii) the proportion of these higher-risk patients in whom TdP risk factor monitoring was performed; (iv) proportion of patients with QT(c) interval prolongation who subsequently received QT-prolonging drugs and who experienced further QT(c) interval prolongation.</AbstractText>Of 1159 patients enrolled, 259 patients met exclusion criteria, resulting in a final sample size of 900 patients.</AbstractText>mean (&#xb1; SD) age, 65&#x2009;&#xb1;&#x2009;15 years; female, 47%; Caucasian, 70%. Admitting diagnoses: heart failure (22%), myocardial infarction (16%), atrial fibrillation (9%), sudden cardiac arrest (3%). QT(c) interval prolongation was present in 27.9% of patients on admission; 18.2% had QT(c) interval &gt;500&#x2009;ms. Of 251 patients admitted with QT(c) interval prolongation, 87 (34.7%) were subsequently administered QT interval-prolonging drugs. Of 166 patients admitted with QT(c) interval &gt;500&#x2009;ms, 70 (42.2%) were subsequently administered QT interval-prolonging drugs; additional QT(c) interval prolongation &#x2265;60&#x2009;ms occurred in 57.1% of these patients.</AbstractText>QT(c) interval prolongation is common among patients admitted to cardiac units. QT interval-prolonging drugs are commonly prescribed to patients presenting with QT(c) interval prolongation.</AbstractText>
14,115
Thrombo-embolism and antithrombotic therapy for heart failure in sinus rhythm. A joint consensus document from the ESC Heart Failure Association and the ESC Working Group on Thrombosis.
Chronic heart failure (HF) with either reduced or preserved ejection fraction is common and remains an extremely serious disorder with a high mortality and morbidity. Many complications related to HF can be related to thrombosis. Epidemiological and pathophysiological data also link HF to an increased risk of thrombosis, leading to the clinical consequences of sudden death, stroke, systemic thrombo-embolism, and/or venous thrombo-embolism. This consensus document of the Heart Failure Association (EHFA) of the European Society of Cardiology (ESC) and the ESC Working Group on Thrombosis reviews the published evidence and summarizes 'best practice', and puts forward consensus statements that may help to define evidence gaps and assist management decisions in everyday clinical practice. In HF patients with atrial fibrillation, oral anticoagulation is recommended, and the CHA(2)DS(2)-VASc and HAS-BLED scores should be used to determine the likely risk-benefit ratio (thrombo-embolism prevention vs. risk of bleeding) of oral anticoagulation. In HF patients with reduced left ventricular ejection fraction who are in sinus rhythm there is no evidence of an overall benefit of vitamin K antagonists (e.g. warfarin) on mortality, with risk of major bleeding. Despite the potential for a reduction in ischaemic stroke, there is currently no compelling reason to use warfarin routinely for these patients. Risk factors associated with increased risk of thrombo-embolic events should be identified and decisions regarding use of anticoagulation individualized. Patient values and preferences are important determinants when balancing the risk of thrombo-embolism against bleeding risk. New oral anticoagulants that offer a different risk-benefit profile compared with warfarin may appear as an attractive therapeutic option, but this would need to be confirmed in clinical trials.
14,116
Meta-analysis of cardiovascular outcomes with dronedarone in patients with atrial fibrillation or heart failure.<Pagination><StartPage>607</StartPage><EndPage>613</EndPage><MedlinePgn>607-13</MedlinePgn></Pagination><ELocationID EIdType="doi" ValidYN="Y">10.1016/j.amjcard.2012.04.034</ELocationID><Abstract><AbstractText>Dronedarone is a benzofuran derivative approved by the Food and Drug Administration to decrease the risk of cardiovascular hospitalization in patients with paroxysmal or persistent atrial fibrillation (AF) and associated cardiovascular risk factors who are in sinus rhythm or will undergo cardioversion. There has been recent evidence to suggest that dronedarone may not have a favorable safety profile. We decided to evaluate all available evidence on the cardiovascular safety of this drug. A systematic search was made of the PubMed, CENTRAL, and EMBASE databases for randomized controlled trials from 1966 through 2011 comparing dronedarone to comparators in AF/heart failure. Intervention was dronedarone for AF for some studies and heart failure for others. Comparators included standard medical therapy and/or placebo and amiodarone for 1 study. Outcomes assessed were all-cause mortality, cardiovascular mortality, ventricular arrhythmias, embolic events, acute coronary syndrome, heart failure exacerbations, and hospitalization rates in the intervention versus comparator group at the end of &#x2265; 3 months of follow up with abstraction of data by 1 author. Seven randomized controlled trials were included in our analysis. Dronedarone use was associated with a trend toward worse all-cause and cardiovascular mortalities and increased heart failure exacerbations. It also showed numerically higher event rates for all other outcome events except acute coronary syndrome. Our pooled analysis showed increased all-cause and cardiovascular mortalities and increased heart failure exacerbations with use of dronedarone across a wide spectrum of populations. In conclusion, we recommend exercising caution using dronedarone, especially in patients with cardiovascular risk factors.</AbstractText><CopyrightInformation>Copyright &#xa9; 2012 Elsevier Inc. All rights reserved.</CopyrightInformation></Abstract><AuthorList CompleteYN="Y"><Author ValidYN="Y"><LastName>Chatterjee</LastName><ForeName>Saurav</ForeName><Initials>S</Initials><AffiliationInfo><Affiliation>Maimonides Medical Center, Brooklyn, New York. sauravchatterjeemd@gmail.com</Affiliation></AffiliationInfo></Author><Author ValidYN="Y"><LastName>Ghosh</LastName><ForeName>Joydeep</ForeName><Initials>J</Initials></Author><Author ValidYN="Y"><LastName>Lichstein</LastName><ForeName>Edgar</ForeName><Initials>E</Initials></Author><Author ValidYN="Y"><LastName>Aikat</LastName><ForeName>Shamik</ForeName><Initials>S</Initials></Author><Author ValidYN="Y"><LastName>Mukherjee</LastName><ForeName>Debabrata</ForeName><Initials>D</Initials></Author></AuthorList><Language>eng</Language><PublicationTypeList><PublicationType UI="D016428">Journal Article</PublicationType><PublicationType UI="D017418">Meta-Analysis</PublicationType></PublicationTypeList><ArticleDate DateType="Electronic"><Year>2012</Year><Month>05</Month><Day>19</Day></ArticleDate></Article><MedlineJournalInfo><Country>United States</Country><MedlineTA>Am J Cardiol</MedlineTA><NlmUniqueID>0207277</NlmUniqueID><ISSNLinking>0002-9149</ISSNLinking></MedlineJournalInfo><ChemicalList><Chemical><RegistryNumber>0</RegistryNumber><NameOfSubstance UI="D000889">Anti-Arrhythmia Agents</NameOfSubstance></Chemical><Chemical><RegistryNumber>JQZ1L091Y2</RegistryNumber><NameOfSubstance UI="D000077764">Dronedarone</NameOfSubstance></Chemical><Chemical><RegistryNumber>N3RQ532IUT</RegistryNumber><NameOfSubstance UI="D000638">Amiodarone</NameOfSubstance></Chemical></ChemicalList><CitationSubset>IM</CitationSubset><MeshHeadingList><MeshHeading><DescriptorName UI="D000638" MajorTopicYN="N">Amiodarone</DescriptorName><QualifierName UI="Q000009" MajorTopicYN="N">adverse effects</QualifierName><QualifierName UI="Q000031" MajorTopicYN="Y">analogs &amp; derivatives</QualifierName><QualifierName UI="Q000627" MajorTopicYN="N">therapeutic use</QualifierName></MeshHeading><MeshHeading><DescriptorName UI="D000889" MajorTopicYN="N">Anti-Arrhythmia Agents</DescriptorName><QualifierName UI="Q000009" MajorTopicYN="Y">adverse effects</QualifierName><QualifierName UI="Q000627" MajorTopicYN="N">therapeutic use</QualifierName></MeshHeading><MeshHeading><DescriptorName UI="D001281" MajorTopicYN="N">Atrial Fibrillation</DescriptorName><QualifierName UI="Q000188" MajorTopicYN="Y">drug therapy</QualifierName><QualifierName UI="Q000401" MajorTopicYN="N">mortality</QualifierName></MeshHeading><MeshHeading><DescriptorName UI="D000077764" MajorTopicYN="N">Dronedarone</DescriptorName></MeshHeading><MeshHeading><DescriptorName UI="D006333" MajorTopicYN="N">Heart Failure</DescriptorName><QualifierName UI="Q000188" MajorTopicYN="Y">drug therapy</QualifierName><QualifierName UI="Q000401" MajorTopicYN="N">mortality</QualifierName></MeshHeading><MeshHeading><DescriptorName UI="D006801" MajorTopicYN="N">Humans</DescriptorName></MeshHeading><MeshHeading><DescriptorName UI="D016032" MajorTopicYN="N">Randomized Controlled Trials as Topic</DescriptorName></MeshHeading><MeshHeading><DescriptorName UI="D016896" MajorTopicYN="N">Treatment Outcome</DescriptorName></MeshHeading></MeshHeadingList></MedlineCitation><PubmedData><History><PubMedPubDate PubStatus="received"><Year>2012</Year><Month>2</Month><Day>27</Day></PubMedPubDate><PubMedPubDate PubStatus="revised"><Year>2012</Year><Month>4</Month><Day>3</Day></PubMedPubDate><PubMedPubDate PubStatus="accepted"><Year>2012</Year><Month>4</Month><Day>3</Day></PubMedPubDate><PubMedPubDate PubStatus="entrez"><Year>2012</Year><Month>5</Month><Day>22</Day><Hour>6</Hour><Minute>0</Minute></PubMedPubDate><PubMedPubDate PubStatus="pubmed"><Year>2012</Year><Month>5</Month><Day>23</Day><Hour>6</Hour><Minute>0</Minute></PubMedPubDate><PubMedPubDate PubStatus="medline"><Year>2012</Year><Month>12</Month><Day>10</Day><Hour>6</Hour><Minute>0</Minute></PubMedPubDate></History><PublicationStatus>ppublish</PublicationStatus><ArticleIdList><ArticleId IdType="pubmed">22608952</ArticleId><ArticleId IdType="doi">10.1016/j.amjcard.2012.04.034</ArticleId><ArticleId IdType="pii">S0002-9149(12)01194-0</ArticleId></ArticleIdList></PubmedData></PubmedArticle><PubmedArticle><MedlineCitation Status="MEDLINE" Owner="NLM"><PMID Version="1">22606887</PMID><DateCompleted><Year>2012</Year><Month>07</Month><Day>10</Day></DateCompleted><DateRevised><Year>2016</Year><Month>10</Month><Day>18</Day></DateRevised><Article PubModel="Print"><Journal><ISSN IssnType="Print">1019-5297</ISSN><JournalIssue CitedMedium="Print"><Issue>5-6</Issue><PubDate><Year>2011</Year><Season>Jul-Sep</Season></PubDate></JournalIssue><Title>Likars'ka sprava</Title><ISOAbbreviation>Lik Sprava</ISOAbbreviation></Journal>[Structural and functional changes of myocardium in Chernobyl disaster clean-up workers with atrial fibrillation].
Dronedarone is a benzofuran derivative approved by the Food and Drug Administration to decrease the risk of cardiovascular hospitalization in patients with paroxysmal or persistent atrial fibrillation (AF) and associated cardiovascular risk factors who are in sinus rhythm or will undergo cardioversion. There has been recent evidence to suggest that dronedarone may not have a favorable safety profile. We decided to evaluate all available evidence on the cardiovascular safety of this drug. A systematic search was made of the PubMed, CENTRAL, and EMBASE databases for randomized controlled trials from 1966 through 2011 comparing dronedarone to comparators in AF/heart failure. Intervention was dronedarone for AF for some studies and heart failure for others. Comparators included standard medical therapy and/or placebo and amiodarone for 1 study. Outcomes assessed were all-cause mortality, cardiovascular mortality, ventricular arrhythmias, embolic events, acute coronary syndrome, heart failure exacerbations, and hospitalization rates in the intervention versus comparator group at the end of &#x2265; 3 months of follow up with abstraction of data by 1 author. Seven randomized controlled trials were included in our analysis. Dronedarone use was associated with a trend toward worse all-cause and cardiovascular mortalities and increased heart failure exacerbations. It also showed numerically higher event rates for all other outcome events except acute coronary syndrome. Our pooled analysis showed increased all-cause and cardiovascular mortalities and increased heart failure exacerbations with use of dronedarone across a wide spectrum of populations. In conclusion, we recommend exercising caution using dronedarone, especially in patients with cardiovascular risk factors.<CopyrightInformation>Copyright &#xa9; 2012 Elsevier Inc. All rights reserved.</CopyrightInformation></Abstract><AuthorList CompleteYN="Y"><Author ValidYN="Y"><LastName>Chatterjee</LastName><ForeName>Saurav</ForeName><Initials>S</Initials><AffiliationInfo><Affiliation>Maimonides Medical Center, Brooklyn, New York. sauravchatterjeemd@gmail.com</Affiliation></AffiliationInfo></Author><Author ValidYN="Y"><LastName>Ghosh</LastName><ForeName>Joydeep</ForeName><Initials>J</Initials></Author><Author ValidYN="Y"><LastName>Lichstein</LastName><ForeName>Edgar</ForeName><Initials>E</Initials></Author><Author ValidYN="Y"><LastName>Aikat</LastName><ForeName>Shamik</ForeName><Initials>S</Initials></Author><Author ValidYN="Y"><LastName>Mukherjee</LastName><ForeName>Debabrata</ForeName><Initials>D</Initials></Author></AuthorList><Language>eng</Language><PublicationTypeList><PublicationType UI="D016428">Journal Article</PublicationType><PublicationType UI="D017418">Meta-Analysis</PublicationType></PublicationTypeList><ArticleDate DateType="Electronic"><Year>2012</Year><Month>05</Month><Day>19</Day></ArticleDate></Article><MedlineJournalInfo><Country>United States</Country><MedlineTA>Am J Cardiol</MedlineTA><NlmUniqueID>0207277</NlmUniqueID><ISSNLinking>0002-9149</ISSNLinking></MedlineJournalInfo><ChemicalList><Chemical><RegistryNumber>0</RegistryNumber><NameOfSubstance UI="D000889">Anti-Arrhythmia Agents</NameOfSubstance></Chemical><Chemical><RegistryNumber>JQZ1L091Y2</RegistryNumber><NameOfSubstance UI="D000077764">Dronedarone</NameOfSubstance></Chemical><Chemical><RegistryNumber>N3RQ532IUT</RegistryNumber><NameOfSubstance UI="D000638">Amiodarone</NameOfSubstance></Chemical></ChemicalList><CitationSubset>IM</CitationSubset><MeshHeadingList><MeshHeading><DescriptorName UI="D000638" MajorTopicYN="N">Amiodarone</DescriptorName><QualifierName UI="Q000009" MajorTopicYN="N">adverse effects</QualifierName><QualifierName UI="Q000031" MajorTopicYN="Y">analogs &amp; derivatives</QualifierName><QualifierName UI="Q000627" MajorTopicYN="N">therapeutic use</QualifierName></MeshHeading><MeshHeading><DescriptorName UI="D000889" MajorTopicYN="N">Anti-Arrhythmia Agents</DescriptorName><QualifierName UI="Q000009" MajorTopicYN="Y">adverse effects</QualifierName><QualifierName UI="Q000627" MajorTopicYN="N">therapeutic use</QualifierName></MeshHeading><MeshHeading><DescriptorName UI="D001281" MajorTopicYN="N">Atrial Fibrillation</DescriptorName><QualifierName UI="Q000188" MajorTopicYN="Y">drug therapy</QualifierName><QualifierName UI="Q000401" MajorTopicYN="N">mortality</QualifierName></MeshHeading><MeshHeading><DescriptorName UI="D000077764" MajorTopicYN="N">Dronedarone</DescriptorName></MeshHeading><MeshHeading><DescriptorName UI="D006333" MajorTopicYN="N">Heart Failure</DescriptorName><QualifierName UI="Q000188" MajorTopicYN="Y">drug therapy</QualifierName><QualifierName UI="Q000401" MajorTopicYN="N">mortality</QualifierName></MeshHeading><MeshHeading><DescriptorName UI="D006801" MajorTopicYN="N">Humans</DescriptorName></MeshHeading><MeshHeading><DescriptorName UI="D016032" MajorTopicYN="N">Randomized Controlled Trials as Topic</DescriptorName></MeshHeading><MeshHeading><DescriptorName UI="D016896" MajorTopicYN="N">Treatment Outcome</DescriptorName></MeshHeading></MeshHeadingList></MedlineCitation><PubmedData><History><PubMedPubDate PubStatus="received"><Year>2012</Year><Month>2</Month><Day>27</Day></PubMedPubDate><PubMedPubDate PubStatus="revised"><Year>2012</Year><Month>4</Month><Day>3</Day></PubMedPubDate><PubMedPubDate PubStatus="accepted"><Year>2012</Year><Month>4</Month><Day>3</Day></PubMedPubDate><PubMedPubDate PubStatus="entrez"><Year>2012</Year><Month>5</Month><Day>22</Day><Hour>6</Hour><Minute>0</Minute></PubMedPubDate><PubMedPubDate PubStatus="pubmed"><Year>2012</Year><Month>5</Month><Day>23</Day><Hour>6</Hour><Minute>0</Minute></PubMedPubDate><PubMedPubDate PubStatus="medline"><Year>2012</Year><Month>12</Month><Day>10</Day><Hour>6</Hour><Minute>0</Minute></PubMedPubDate></History><PublicationStatus>ppublish</PublicationStatus><ArticleIdList><ArticleId IdType="pubmed">22608952</ArticleId><ArticleId IdType="doi">10.1016/j.amjcard.2012.04.034</ArticleId><ArticleId IdType="pii">S0002-9149(12)01194-0</ArticleId></ArticleIdList></PubmedData></PubmedArticle><PubmedArticle><MedlineCitation Status="MEDLINE" Owner="NLM"><PMID Version="1">22606887</PMID><DateCompleted><Year>2012</Year><Month>07</Month><Day>10</Day></DateCompleted><DateRevised><Year>2016</Year><Month>10</Month><Day>18</Day></DateRevised><Article PubModel="Print"><Journal><ISSN IssnType="Print">1019-5297</ISSN><JournalIssue CitedMedium="Print"><Issue>5-6</Issue><PubDate><Year>2011</Year><Season>Jul-Sep</Season></PubDate></JournalIssue><Title>Likars'ka sprava</Title><ISOAbbreviation>Lik Sprava</ISOAbbreviation></Journal><ArticleTitle>[Structural and functional changes of myocardium in Chernobyl disaster clean-up workers with atrial fibrillation].</ArticleTitle><Pagination><StartPage>18</StartPage><EndPage>24</EndPage><MedlinePgn>18-24</MedlinePgn></Pagination><Abstract>Particularities and clinical importance of the structural and functional changes of myocardium were estimated in Chernobyl disaster clean-up workers with atrial fibrillation (AF). We examined 122 men with AF, which was associated with ischemic heart disease and arterial hypertension. Paroxysmal AF was diagnosed in 42 patients, 80 patients had permanent AE Control group comprised 80 men without AF. Echocardiography and Doppler studies were performed using ultrasound scanner Aloka SSD-630 (Japan). Significant structural and functional changes of the heart were revealed already in paroxysmal AF and became more pronounced in permanent AF. Increased left atrial size, its ratio to left ventricular end diastolic diameter, diastolic dysfunction were important echocardiographic predictors of AF. Heart walls thickening was accompanied by disorders of myocardial relaxation, increase in myocardial mass led to ischemia, and together they promoted overload, dysfunction of atrium and development of AF. Obligatory echocardiographic examination of the Chernobyl disaster clean-up workers with ischemic heart disease and arterial hypertension is necessary for predicting AF early, ordering adequate therapy in proper time and improving prognosis.
14,117
Accidental intrathecal injection of tranexamic Acid.
Tranexamic acid (TXA) is a popular antifibrinolytic drug that is commonly used in patients with bleeding disorder. Major morbidities and mortalities have been reported following inadvertent intrathecal injection of TXA. In this paper, inadvertent intrathecal injection of TXA has resulted from similarities in appearance between TXA and heavy bupivacaine 0.5% ampoules. The patient experienced severe pain in the back and gluteal region upon injection in association with systemic hypertension and tachycardia followed by generalized myoclonic seizures and ventricular fibrillation.
14,118
ECG telemonitoring during home-based cardiac rehabilitation in heart failure patients.
We assessed ECGs recorded during home-based telemonitored cardiac rehabilitation (HTCR) in stable patients with heart-failure. The study included 75 patients with heart failure (NYHA II, III), with a mean age of 56 years. They participated in an eight-week programme of home cardiac rehabilitation which was telemonitored with a device which recorded 16-s fragments of their ECG. These fragments were transmitted via mobile phone to a monitoring centre. The times of the automatic ECG recordings were pre-set and coordinated with the cardiac rehabilitation. Patients were able to make additional recordings when they felt unwell using a tele-event-Holter ECG facility. During the study, 5757 HTCR sessions were recorded and 11,534 transmitted ECG fragments were evaluated. Most ECGs originated from the automatic recordings. Singular supraventricular and ventricular premature beats and ventricular couplets were detected in 16%, 69% and 16% of patients, respectively. Twenty ECGs were recorded when patients felt unwell: non sustained ventricular tachycardia occurred in three patients and paroxysmal atrial fibrillation episode in two patients. Heart failure patients undergoing HTCR did not develop any arrhythmia which required a change of the procedure, confirming it was safe. Cardiac rehabilitation at home was improved by utilizing the tele-event-Holter ECG facility.
14,119
Tension pneumoperitoneum complicated with tension pneumothorax in a patient with diaphragmatic eventration.
Tension pneumothorax complicating a pneumoperitoneum is a rare but known entity. However, all previously published articles report an air leak through defects in the diaphragm connecting the pneumoperitoneum and the pneumothorax. Here, the case of a 36-year-old man in whom the pneumoperitoneum acted like a tension pneumothorax because of a congenital eventration of the left diaphragm without penetration is presented. Emergency needle decompression of the abdomen was performed. A gastric ulcer that had passed through the diaphragm to the right lung was diagnosed intraoperatively. Unfortunately, the patient developed a ventricular fibrillation that remained resistant to all resuscitative efforts, and the patient died shortly afterwards.
14,120
Causes of in-hospital cardiac arrest and influence on outcome.
To evaluate the relationship between cause and outcome of in-hospital cardiac arrest.</AbstractText>Retrospective analysis of resuscitation data, causes of cardiac arrest and outcome with a follow-up to 6 months of a cardiac arrest registry in an emergency department of a tertiary care hospital, covering a 17.5-year period.</AbstractText>Of 1041 patients, 653 were male (63%), the median age was 64 years (IQR 53-73), 51% suffered cardiac arrest in the emergency department. The first recorded rhythm showed PEA in 432 (41%), ventricular fibrillation in 404 (39%) and asystole in 205 (20%) patients. Cardiac arrest of cardiac origin occurred in 63% of all patients, with 35% of them due to acute myocardial infarction. Non-cardiac causes were mostly due to pulmonary causes (15% of all patients). Aortic dissection/rupture, exsanguination, intoxication and adverse drug reactions, metabolic, cerebral, sepsis and accidental hypothermia each ranged between 1 and 4% of the cohort. Of all patients, 376 (36%) were discharged in good neurologic condition. Overall, patients with cardiac causes had a significantly better outcome than those with non-cardiac causes (44% vs. 23%, p&lt;0.01). Patients with pulmonary causes survived in 24%. The other subgroups showed widely divergent survival results (3-65%). Patients who had suffered cardiac arrest in the emergency department had a better outcome then patients of the regular ward or radiology department.</AbstractText>In hospital cardiac arrest is caused mainly by cardiac and pulmonary causes, outcome depends on the cause, with a big variability.</AbstractText>Copyright &#xa9; 2012 Elsevier Ireland Ltd. All rights reserved.</CopyrightInformation>
14,121
[Computer modeling of ventricular fibrillation].
Electrical activity of a heart in ventricular fibrillation was modeled as a sum of independent pulse streams with various amplitude-frequency and phase characteristics. Results of computer experiments were compared with those of real physiological experiments on rabbits. Identification of the model was carried out by means of the least-squares procedure. The offered technique allows a computer model investigation of internal structure of irregularities of ventricular fibrillation.
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Ventricular muscarinic receptor remodeling in patients with and without primary ventricular fibrillation. An imaging study.
Vagal innervation modulates the electrical stability of the left ventricle (LV) during ischemia. Thus, abnormal parasympathetic activity in myocardial infarction (MI) patients with primary ventricular fibrillation (FV) can account for their arrhythmic disorders. We evaluated LV muscarinic receptor density (B (max)) after MI in patients with (FV(G), n = 11) or without (nFV(G), n = 12) primary FV.</AbstractText>The B (max) was measured by positron emission tomography and the specific antagonist [(11)C]methylquinuclidinyl benzilate ([(11)C]MQNB) in 23 patients 39 &#xb1; 19 days post-MI, and 10 volunteers. Myocardial damage was quantified by delayed contrast-enhanced magnetic resonance imaging. Three short-axis slices per subject were analyzed and six time-activity curves per slice were fitted to a 3-compartment ligand-receptor model. The B (max) in remote regions of the 23 patients (67 &#xb1; 36 pmol/mL &#xb7; tissue; n = 139) was higher than in normal regions of volunteers (33 &#xb1; 16 pmol/mL &#xb7; tissue; n = 171; P = .01). Receptor density in remote regions was similarly upregulated in nFV(G) (69 &#xb1; 31 pmol/mL &#xb7; tissue, n = 73) and FV(G) (66 &#xb1; 40 pmol/mL &#xb7; tissue, n = 66; P = .72). In damaged regions, the B (max) was reduced in both patient groups (44 pmol/mL &#xb7; tissue).</AbstractText>Chronically infarcted patients with or without primary FV share similar patterns of ventricular muscarinic receptor remodeling, characterized by receptor upregulation, in remote non-damaged territories.</AbstractText>
14,123
Extracorporeal membrane oxygenation-assisted primary percutaneous coronary intervention may improve survival of patients with acute myocardial infarction complicated by profound cardiogenic shock.
The aim of this study was to evaluate the impact of extracorporeal membrane oxygenation (ECMO) assistance on the clinical outcome of patients with acute myocardial infarction (AMI) that is complicated by profound cardiogenic shock (CS) who received primary percutaneous coronary intervention (PCI).</AbstractText>We collected patients from January 2004 through December 2006 (stage 1); 25 patients who presented with AMI and received primary PCI and had profound CS were enrolled in the study. Intraaortic balloon counterpulsation (IABP) was the only modality for extracorporeal support in our hospital. From January 2007 through December 2009 (stage 2), 33 patients who presented with AMI and received primary PCI and had profound CS were enrolled; for this stage; both intra-aortic balloon counter-pulsation and ECMO support were available in our facility.</AbstractText>A Kaplan-Meier survival analysis displayed significantly improved survival for patients in stage 2 (P = .001; 1-year survival in stage 1 vs 2; 24% vs 63.64%). Patients presenting with either STEMI (ST segment elevation myocardial infarction) or NSTEMI (Non-ST segment elevation myocardial infarction) benefited from ECMO-assisted PCI (P &lt; .05). In stage 1, patients with refractory ventricular tachycardia/ventricular fibrillation had a very low survival rate; however, in stage 2, the survival rate of patients with and without refractory ventricular tachycardia/ventricular fibrillation was similar (P = .316).</AbstractText>Extracorporeal membrane oxygenation-assisted PCI for patients with AMI that is complicated by profound CS may improve the 30-day and 1-year survival rates.</AbstractText>Copyright &#xa9; 2012 Elsevier Inc. All rights reserved.</CopyrightInformation>
14,124
Recurrence of ventricular fibrillation in a patient with non-type 1 Brugada electrocardiographic morphology.
A healthy 25-year-old man suffered from loss of consciousness due to ventricular fibrillation (VF). Emergency services required multiple cardioversion to restore sinus rhythm. Repeated electrocardiographic (ECG) recordings after admission showed non-type 1 Brugada ST-segment elevation in V1 and V2. Intravenous pilsicainide infusion augmented the ST-segment elevation but its morphology did not represent type-1 ECG. Intravenous administration of isoproterenol normalized the ST-segment elevation, and programmed electrical stimulation induced VF. Spontaneous VF recurred 1 year after introduction of implantable cardioverter defibrillator. Non-type 1 ST-segment elevation, to which pharmacological responses are similar to Brugada syndrome, may be used as a hallmark of ventricular tachyarrhythmia.
14,125
Sudden death of cardiac origin and psychotropic drugs.
Mortality rate is high in psychiatric patients versus general population. An important cause of this increased mortality is sudden cardiac death (SCD) as a major side-effect of psychotropic drugs. These SCDs generally result from arrhythmias occurring when the posology is high and may attain a toxic threshold but also at dosages within therapeutic range, in the presence of risk factors. There are three kinds of risk factors: physiological (e.g., low cardiac rate of sportsmen), physiopathological (e.g., hepatic insufficiency, hypothyroidism) and "therapeutic" (due to interactions between psychotropic drugs and other medicines). Association of pharmacological agents may increase the likelihood of SCDs either by (i) a pharmacokinetic mechanism (e.g., increased torsadogenic potential of a psychotropic drug when its destruction and/or elimination are compromised) or (ii) a pharmacodynamical mechanism (e.g., mutual potentiation of proarrhythmic properties of two drugs). In addition, some psychotropic drugs may induce sudden death in cases of pre-existing congenital cardiopathies such as (i) congenital long QT syndrome, predisposing to torsade de pointes that eventually cause syncope and sudden death. (ii) A Brugada syndrome, that may directly cause ventricular fibrillation due to reduced sodium current through Nav1.5 channels. Moreover, psychotropic drugs may be a direct cause of cardiac lesions also leading to SCD. This is the case, for example, of phenothiazines responsible for ischemic coronaropathies and of clozapine that is involved in the occurrence of myocarditis. The aims of this work are to delineate: (i) the risk of SCD related to the use of psychotropic drugs; (ii) mechanisms involved in the occurrence of such SCD; (iii) preventive actions of psychotropic drugs side effects, on the basis of the knowledge of patient-specific risk factors, documented from clinical history, ionic balance, and ECG investigation by the psychiatrist.
14,126
Adverse effects of permanent atrial fibrillation on heart failure in patients with preserved left ventricular function and chronic right apical pacing for complete heart block.
The impact of atrial fibrillation (AF) on heart failure (HF) was evaluated in patients with preserved left ventricular (LV) function and long-term right ventricular (RV) pacing for complete heart block.</AbstractText>Clinical, echocardiographic, and laboratory parameters of HF were assessed in 35 patients with established AF who had undergone ablation of the atrioventricular node and pacemaker implantation (Group A) and 31 patients who received dual-chamber pacing for spontaneous complete heart block (Group B).</AbstractText>During a follow-up period of 12.7&#xa0;&#xb1;&#xa0;7.5&#xa0;years, New York Heart Association (NYHA) functional class increased from 1.3&#xa0;&#xb1;&#xa0;0.5 to 2.1&#xa0;&#xb1;&#xa0;0.6 (p&#xa0;&lt;&#xa0;0.0001) in Group A, and from 1.3&#xa0;&#xb1;&#xa0;0.4 to 1.6&#xa0;&#xb1;&#xa0;0.7 (p&#xa0;&lt;&#xa0;0.01) in Group B. Left ventricular ejection fraction (LVEF) decreased from 59.7&#xa0;&#xb1;&#xa0;5.1 to 53.0&#xa0;&#xb1;&#xa0;8.2&#xa0;(p&#xa0;&lt;&#xa0;0.0001) in Group A, but remained stable (58.6&#xa0;&#xb1;&#xa0;4.2 vs. 56.9&#xa0;&#xb1;&#xa0;7.0&#xa0;%, p&#xa0;=&#xa0;0,21) in Group B. At the end of follow-up, markers of LV function were moderately depressed in Group A compared with those in Group B: NYHA class 2.1&#xa0;&#xb1;&#xa0;0.6 versus 1.6&#xa0;&#xb1;&#xa0;0.7, p&#xa0;=&#xa0;0.001; LVEF 53.0&#xa0;&#xb1;&#xa0;8.2 versus 56.9&#xa0;&#xb1;&#xa0;7.0&#xa0;%, p&#xa0;&lt;&#xa0;0.05; LV diastolic diameter 53.6&#xa0;&#xb1;&#xa0;5.8&#xa0;mm versus 50.7&#xa0;&#xb1;&#xa0;4.9&#xa0;mm, p&#xa0;&lt;&#xa0;0.05; N-terminal pro-brain natriuretic peptide (NT-proBNP) 1116.8&#xa0;&#xb1;&#xa0;883.9 versus 622.9&#xa0;&#xb1;&#xa0;1059.4&#xa0;pg/ml, p&#xa0;&lt;&#xa0;0.05. Progression of paroxysmal AF to permanent AF during follow-up was common, while new onset of AF was rare. Permanent AF was an independent predictor of declining LVEF &gt;10&#xa0;%, increasing NYHA class &#x2265;1, and NT-proBNP levels &gt;1,000&#xa0;pg/ml.</AbstractText>Permanent AF was associated with adverse effects on LV function and symptoms of HF in patients with long-term RV pacing for complete heart block, and appears to play an important role in the development of HF in this specific patient cohort.</AbstractText>
14,127
Novel computed tomography indexes of left atrial appendage stasis.
Contrast enhanced multi-detector computed tomography (MDCT) may detect left atrial appendage (LAA) thrombus; however, its ability to qualify LAA stasis has not been studied. We sought to identify MDCT derived LAA radiographic parameters which could qualify LAA stasis as defined by established transesophageal echocardiography (TEE) parameters. Pre-procedural MDCT followed by TEE (median procedural time difference of 11 days) from 45 patients who underwent ablation for atrial fibrillation were analyzed retrospectively. Contrast enhanced, non-gated, helical MDCT (64 detector row) was performed according to the institutional protocol. Using a combination of parametric and nonparametric tests, the mean attenuation and heterogeneity parameters of LAA attenuation were correlated with the presence of spontaneous echocardiographic contrast and Doppler derived LAA emptying velocity on TEE. If significant correlation is observed, a receiver operating curve analysis will be performed. The baseline characteristics of the studied population were; age, 62 &#xb1; 11; CHADS2 score, 2.0 &#xb1; 1.2; heart rate, 79 &#xb1; 10 bpm; left ventricular ejection fraction, 49 &#xb1; 14%. SEC was seen on TEE in 19 patients; ten with mild, eight with moderate, and one had severe SEC. No patients had LAA thrombus. Compared with the group without SEC, those with SEC had significantly increased coefficient of variation (0.19 vs. 0.14, p = 0.014) and range to mean ratio (1.04 vs. 0.73, p = 0.011). There was no significant correlation between mean LAA attenuation and LAA emptying velocity. However, the range, range to mean ratio, standard deviation and coefficient of variation of LAA attenuation had a significantly negative correlation with LAA emptying velocity (r = -0.486, r = -0.497, r = -0.434, r = -0.466, respectively, all p &lt; 0.05). On receiver operating curve analysis, each of the heterogeneity parameters significantly discriminated LAA emptying velocities &#x2264;30 cm/s, with areas under the curve of 0.88, 0.83, 0.81 and 0.76 respectively. In patients with atrial fibrillation, increased contrast heterogeneity within the LAA on MDCT correlated with decreased LAA emptying velocity on TEE. Contrast enhanced MDCT provides an adjunctive, noninvasive technique for Qualification of LAA stasis.
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Xanthine oxidase inhibition prevents atrial fibrillation in a canine model of atrial pacing-induced left ventricular dysfunction.
Oxidative stress could be a possible mechanism and a therapeutic target of atrial fibrillation (AF). Xanthine oxidase (XO) inhibition reduces oxidative stress, but the effects of XO inhibitor on AF have not been evaluated. Hence, we assessed the effects of XO inhibitor, allopurinol, on progression of atrial vulnerability in dogs associated with tachycardia-induced cardiomyopathy.</AbstractText>The dogs were subjected to atrial tachypacing (ATP, 400 bpm) without atrioventricular block for 4 weeks. The dynamics of atrial-tachycardia remodeling were evaluated in allopurinol-treated dogs (ALO, n = 5), placebo-treated controls (CTL, n = 6), and sham-operated dogs (n = 6). In CTL dogs, 4 weeks of ATP significantly increased AF duration (DAF; from 0.2 &#xb1; 0.2 seconds to 173 &#xb1; 67 seconds, P &lt; 0.05) and decreased atrial effective refractory period (ERP; from 152 &#xb1; 9 milliseconds to 80 &#xb1; 4 milliseconds at a cycle length of 350 milliseconds, P &lt; 0.01). Allopurinol attenuated the ATP effects on ERP (118 &#xb1; 6 milliseconds, P &lt; 0.01) or DAF (0.6 &#xb1; 0.3 seconds, P &lt; 0.05). In CTL dogs, ATP-induced rapid ventricular responses decreased left ventricular ejection fraction (LVEF; from 58.6 &#xb1; 0.1 to 23.5 &#xb1; 2.4%, P &lt; 0.01), and increased left atrial diameter (LAD; from 17 &#xb1; 1 mm to 24 &#xb1; 1 mm, P &lt; 0.01). ATP increased atrial fibrosis when compared with sham-operated dogs (CTL 10.7 &#xb1; 0.8% vs Sham 1.1 &#xb1; 0.3%, P &lt; 0.01). Allopurinol suppressed atrial fibrosis (2.3 &#xb1; 0.6%, P &lt; 0.01 vs CTL) and eNOS reduction without affecting LVEF (20.6 &#xb1; 2.2%, ns) and LAD (23 &#xb1; 1 mm, ns).</AbstractText>Allopurinol suppresses AF promotion by preventing both electrical and structural remodeling. These results suggest that XO may play an important role in enhancement of atrial vulnerability, and might be a novel target of AF therapy.</AbstractText>&#xa9; 2012 Wiley Periodicals, Inc.</CopyrightInformation>
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Low rate of atrial fibrillation recurrence verified by implantable loop recorder monitoring following a convergent epicardial and endocardial ablation of atrial fibrillation.
Evaluate long-term outcomes in patients undergoing the Convergent procedure (CP) for the treatment of atrial fibrillation (AF).</AbstractText>The CP provides a multidisciplinary approach, combining endoscopic creation of epicardial linear lesions followed by endocardial mapping and ablation and targets persistent and longstanding persistent AF patients who are at increased risk of heart failure, stroke, and mortality.</AbstractText>Outcomes from a prospective nonrandomized study were recorded for consecutive patients by interrogation of implanted Reveal monitors. Rhythm status and AF burden were quantified 6-24 months postprocedure, and compared relative to AF type, gender, age, body mass index, left atrial size, left ventricular ejection fraction, and congestive heart failure, hypertension, age &gt;75 years, age between 65 and 74 years, stroke/TIA/TE, vascular disease (previous MI, peripheral arterial disease or aortic plaque), diabetes mellitus, female (CHA(2) DS(2) VASc).</AbstractText>A total of 50 patients were enrolled with 94% having persistent or longstanding persistent AF. There were 2 atrioesophageal fistulas reported. In one patient, the fistula resulted in death at 33 days postprocedure; in the second, the fistula was surgically repaired but patient died 8 months postprocedure from a CVI. After CP, 95% of patients were in sinus rhythm at 6-month follow-up; 88% at 12 months; and 87% at 24 months. The median AF burden recorded with Reveal XT monitors was 0.0%, 0.1%, and 0.1% at 6, 12, and 24 months with 81%, 81%, and 87% of patients reporting a burden less than 3%, respectively.</AbstractText>Using 24 &#xd7; 7 continuous loop recording, the CP demonstrated success in treating persistent and longstanding persistent AF patients. Endocardial mapping and catheter ablation with diagnostic confirmation of procedural success complemented the endoscopic creation of epicardial linear lesions in restoring sinus rhythm.</AbstractText>&#xa9; 2012 Wiley Periodicals, Inc.</CopyrightInformation>
14,130
The prevalence of early repolarization in patients with noncompaction cardiomyopathy presenting with malignant ventricular arrhythmias.
Early Repolarization in Noncompaction Cardiomyopathy.&#x2002;</AbstractText>Early repolarization (ER) is associated with malignant ventricular arrhythmias, including ventricular fibrillation (VF) and sudden cardiac death (SCD). One possible mechanism is increased trabeculation with deep intramyocardial invagination, carrying the Purkinje system deeper into the myocardium resulting in delayed depolarization and inhomogenous repolarization. Noncompaction cardiomyopathy (NCCM) is a recently classified, primary cardiomyopathy with excessive trabeculations. In these patients ventricular arrhythmias, including sustained VT and VF, occur frequently. The aim of this study was to determine the prevalence of ER in NCCM patients, especially in those primarily presenting with malignant ventricular arrhythmias or SCD.</AbstractText>We analyzed prospective data from our NCCM registry including 84 patients, median age: 40 (3-79) years.</AbstractText>Fourteen patients (17%) initially presented with sustained VT (n = 5) or VF (n = 9) and 70 (83%) with heart failure or else. After the exclusion of 20 patients with the left bundle branch block, 25 (39%) NCCM patients had ER; 3 (6%) located in inferior leads, 14 (27%) in lateral leads, and 8 (15%) in both. None had ER in leads V1 to V3. In those presenting with VT/VF, 9/12 (75%) had ER (2 in inferior leads, 3 in lateral leads and 4 in both), versus 16/52 (31%) in the other patients (P = 0.02). If the NCCM population was dichotomized according to the presence or absence of ER, the long-term outcome for VT/VF appeared worse in the ER positive patients (P = 0.05).</AbstractText>There is a high prevalence of ER in NCCM patients, especially in those who present with malignant ventricular arrhythmias. (J Cardiovasc Electrophysiol, Vol. 23, pp. 938-944, September 2012).</AbstractText>&#xa9; 2012 Wiley Periodicals, Inc.</CopyrightInformation>
14,131
Defects in cytoskeletal signaling pathways, arrhythmia, and sudden cardiac death.
Ankyrin polypeptides are cellular adapter proteins that tether integral membrane proteins to the cytoskeleton in a host of human organs. Initially identified as integral components of the cytoskeleton in erythrocytes, a recent explosion in ankyrin research has demonstrated that these proteins play prominent roles in cytoskeletal signaling pathways and membrane protein trafficking/regulation in a variety of excitable and non-excitable cells including heart and brain. Importantly, ankyrin research has translated from bench to bedside with the discovery of human gene variants associated with ventricular arrhythmias that alter ankyrin-based pathways. Ankyrin polypeptides have also been found to play an instrumental role in various forms of sinus node disease and atrial fibrillation (AF). Mouse models of ankyrin-deficiency have played fundamental roles in the translation of ankyrin-based research to new clinical understanding of human sinus node disease, AF, and ventricular tachycardia.
14,132
Neural control of ventricular rate in ambulatory dogs with pacing-induced sustained atrial fibrillation.
We hypothesize that inferior vena cava-inferior atrial ganglionated plexus nerve activity (IVC-IAGPNA) is responsible for ventricular rate (VR) control during atrial fibrillation (AF) in ambulatory dogs.</AbstractText>We recorded bilateral cervical vagal nerve activity (VNA) and IVC-IAGPNA during baseline sinus rhythm and during pacing-induced sustained AF in 6 ambulatory dogs. Integrated nerve activities and average VR were measured every 10 seconds over 24 hours. Left VNA was associated with VR reduction during AF in 5 dogs (from 211 bpm [95% CI, 186-233] to 178 bpm [95% CI, 145-210]; P&lt;0.001) and right VNA in 1 dog (from 208 bpm [95% CI, 197-223] to 181 bpm [95% CI, 163-200]; P&lt;0.01). There were good correlations between IVC-IAGPNA and left VNA in the former 5 dogs and between IVC-IAGPNA and right VNA in the last dog. IVC-IAGPNA was associated with VR reduction in all dogs studied. Right VNA was associated with baseline sinus rate reduction from 105 bpm (95% CI, 95-116) to 77 bpm (95% CI, 64-91; P&lt;0.01) in 4 dogs, whereas left VNA was associated with sinus rate reduction from 111 bpm (95% CI, 90-1250) to 81 bpm (95% CI, 67-103; P&lt;0.01) in 2 dogs.</AbstractText>IVC-IAGPNA is invariably associated with VR reduction during AF. In comparison, right or left VNA was associated with VR reduction only when it coactivates with the IVC-IAGPNA. The vagal nerve that controls VR during AF may be different from that which controls sinus rhythm.</AbstractText>
14,133
[Sudden cardiac death of rhythmic origin in athletes: literature review].
The sudden death in athletes is, in the vast majority of cases, related to ventricular fibrillation, often in a subject with unknown cardiovascular abnormality; this dramatic event has a significant impact on society and the medical profession. We conducted through a literature review an analysis of data on sudden cardiac death of rhythmic origin in athletes; sudden death may be cardiovascular in 95.3% of cases and related to ventricular arrhythmia in 88% cases. The main causes are: hypertrophic cardiomyopathy, congenital anomalies of coronary arteries, and arhythmogenic right ventricular dysplasia for athletes under 35 years, and atherosclerosis beyond 35 years. Prevention is based on three main areas: the medical assessment and screening for cardiovascular disease; the chain of survival; the education of the athlete and the public. All these measures should improve significantly the survival prognosis of patients suffering from these accidents.
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QRS prolongation induced by cardiac resynchronization therapy correlates with deterioration in left ventricular function.
The benefits of cardiac resynchronization in inducing reverse ventricular remodeling in patients with left ventricular (LV) systolic dysfunction have been well established. Still, up to 30% of the patients fail to derive significant improvement from this therapy. A subset of "nonresponders" experience deterioration in LV function following cardiac resynchronization therapy (CRT). Characteristics of this patient population, however, have not been studied.</AbstractText>To determine characteristics of patients who experience deterioration in LV function following CRT.</AbstractText>Clinical, electrocardiographic, and echocardiographic data were collected in 856 consecutive patients presenting for a new CRT device. For inclusion, all patients had an LV ejection fraction '40%, a QRS duration '120 ms, and available baseline and follow-up echocardiograms and electrocardiograms. Deterioration in LV function was defined as an absolute decrease of 5% or greater in ejection fraction from baseline. Multivariate models were constructed to identify variables significantly associated with deterioration.</AbstractText>A total of 507 patients met inclusion criteria, of which 60 (11.8%) met criteria for deterioration. Patients with deterioration were more likely to be men (86.7% vs 66.9%; P = .002), have a non-left bundle branch block morphology (41.7% vs 23.7%; P = .001), and a history of atrial fibrillation (66.7% vs 51.7%; P = .03). On comparing the pre-CRT QRS duration with the first biventricular-paced QRS duration post-CRT implant, it was found that patients with LV deterioration had significant QRS widening than did those without deterioration (ms) (+3.9 &#xb1; 34.1 vs -9.0 &#xb1; 27.4, P = .007, respectively). In multivariate analysis, QRS widening indexed to the baseline QRS duration was significantly associated with LV deterioration (odds ratio 1.14 [1.06-1.23]; P = .001).</AbstractText>QRS widening is associated with deterioration in LV function following CRT.</AbstractText>Copyright &#xa9; 2012 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.</CopyrightInformation>
14,135
Transthoracic Echocardiography with Doppler Tissue Imaging predicts weaning failure from mechanical ventilation: evolution of the left ventricle relaxation rate during a spontaneous breathing trial is the key factor in weaning outcome.
There is growing evidence to suggest that transthoracic echocardiography (TTE) should be used to identify the cardiac origin of respiratory weaning failure.</AbstractText>first, to evaluate the ability of transthoracic echocardiography, with mitral Doppler inflow E velocity to annular tissue Doppler Ea wave velocity (E/Ea) ratio measurement, to predict weaning failure from mechanical ventilation in patients, including those with atrial fibrillation; and second, to determine whether the depressed left ejection fraction and/or diastolic dysfunction participate in weaning outcome.</AbstractText>The sample included patients on mechanical ventilation for over 48 hours. A complete echocardiography was performed just before the spontaneous breathing trial (SBT) and 10 minutes after starting the SBT. Systolic dysfunction was defined by a left ventricle ejection fraction under 50% and relaxation impairment by a protodiastolic annulus mitral velocity Ea under or equal to 8 cm/second.</AbstractText>A total of 68 patients were included. Twenty failed the weaning process and the other 48 patients succeeded. Before the SBT, the E/Ea ratio was higher in the failed group than in the successful group. The E/Ea measured during the SBT was also higher in the failed group. The cut-off value, obtained from receiver operating characteristics (ROC) curve analysis, to predict weaning failure gave an E/Ea ratio during the SBT of 14.5 with a sensitivity of 75% and a specificity of 95.8%. The left ventricular ejection fraction did not differ between the two groups whereas Ea was lower in the failed group. Ea increased during SBT in the successful group while no change occurred in the failed group.</AbstractText>Measurement of the E/Ea ratio with TTE could predict weaning failure. Diastolic dysfunction with relaxation impairment is strongly associated with weaning failure. Moreover, the impossibility of enhancing the left ventricle relaxation rate during the SBT seems to be the key factor of weaning failure. In contrast, the systolic dysfunction was not associated with weaning outcome.</AbstractText>
14,136
A low tilt waveform in the transthoracic defibrillation of ventricular arrhythmias during cardiac arrest.
Most commercially available defibrillators utilise a high tilt waveform. Work in atrial fibrillation has shown improved defibrillation success using low tilt waveforms. We hypothesise that a novel low tilt biphasic waveform will be non-inferior to a standard tilt waveform whilst delivering lower energy for the defibrillation of ventricular arrhythmias.</AbstractText>Patients in cardiac arrest who experienced ventricular arrhythmias received shocks from a novel low tilt waveform defibrillator at 120J or a standard tilt waveform defibrillator at 150J. Resuscitation guidelines were followed as per Resuscitation Council UK, 2005. A shock was successful when the ventricular arrhythmia was terminated for &#x2265; 5s following shock delivery.</AbstractText>A total of 113 cardiac arrest cases were included. The low tilt device was used for 56 cases and the standard tilt device for 57 cases. The presenting rhythm was ventricular fibrillation (VF) in 71.7% (81/113), pulseless electrical activity (PEA) in 15.9% (18/113), ventricular tachycardia (VT) in 9.7% (11/113), asystole in 1.8% (2/113) and narrow complex rhythm in 0.9% (1/113). The low tilt device resulted in first shock success in 86% (48/56 cases) vs. the standard tilt device first shock success of 77% (44/57 cases). There was no significant difference in first shock success between the two devices (p=0.36).</AbstractText>The low tilt waveform used in this study demonstrated first shock success rates in keeping with a commercially available high tilt defibrillator which could result in less myocardial damage due to reduced energy requirements.</AbstractText>Crown Copyright &#xa9; 2012. Published by Elsevier Ireland Ltd. All rights reserved.</CopyrightInformation>
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Long-term results of the Maze procedure in patients with mechanical valve.
The advantage of the Maze procedure concomitant with the mechanical valve implantation is unclear. This study evaluated the long-term results of mechanical valve implantation either alone or concomitant with the Maze procedure.</AbstractText>Between 1990 and 2005, 208 patients underwent mitral valve replacement with a mechanical valve. Maze procedure was concomitantly performed in 77 patients, and 54 of these had restored sinus rhythm (Maze group). The other 131 patients did not perform the Maze procedure (non-Maze group). Survival and late outcomes were studied retrospectively with univariate analysis (log-rank test), and a case-matched study by propensity score was performed. The late New York Heart Association (NYHA) functional status obtained by questionnaire and the cardiac function observed by echocardiography were studied for comparison of the two groups.</AbstractText>Survival and late outcomes, except for bleeding, were not significantly different between the groups, and this was also true of the case-matched study. In the NYHA functional status, the Maze group had more class I patients, while the non- Maze group has more class II patients. The left ventricular ejection fraction, left atrial enlargement, and tricuspid regurgitation were not significant factors affecting the differences between class I and II patients.</AbstractText>The Maze procedure is considered to be worth for patients who need life-long anticoagulation for the mechanical valve because it improves the NYHA functional status.</AbstractText>
14,138
Catheter ablation for atrial fibrillation.
Atrial fibrillation (AF) is the most common clinically important cardiac arrhythmia. It is an important cause of stroke, contributes to the burden of heart failure and is a major contributor to health expenditure. Percutaneous catheter ablation is superior to medical therapy in reducing AF recurrences. It has an important role in treatment of patients with failed drug therapy. Successful catheter ablation improves left ventricular function in patients with heart failure. In addition, it may be appropriate for selected highly symptomatic patients as first line therapy. Catheter ablation for AF has been shown in randomised trials to reduce hospital admissions and improve quality of life. There is evidence from registry data to suggest it reduces the risk of stroke and improves mortality. Cost effectiveness has been demonstrated by modelling studies in both Europe and the United States.
14,139
Association of heart rate and outcomes in a broad spectrum of patients with chronic heart failure: results from the CHARM (Candesartan in Heart Failure: Assessment of Reduction in Mortality and morbidity) program.
The aim of this study was to explore the relationship between baseline resting heart rate and outcomes in patients with chronic heart failure (HF) according to baseline left ventricular ejection fraction (LVEF) and cardiac rhythm.</AbstractText>Elevated resting heart rate is associated with worse outcomes in patients with HF and reduced LVEF. Whether this association is also found in patients with HF and preserved LVEF is uncertain, as is the predictive value of heart rate in patients in atrial fibrillation (AF).</AbstractText>Patients enrolled in the CHARM (Candesartan in Heart failure: Assessment of Reduction in Mortality and morbidity) Program were divided into groups by tertiles of baseline heart rate. Cox proportional hazard models were used to investigate the association between heart rate and pre-specified outcomes in the overall population as well as in subgroups defined according to LVEF (&#x2264; 40% vs. &gt;40%) and presence (or absence) of AF at baseline.</AbstractText>After adjusting for predictors of poor prognosis, patients in the highest heart rate tertile had worse outcomes when compared with those in the lowest heart rate group (e.g., for the composite of cardiovascular death or HF hospital stay hazard ratio: 1.23, 95% confidence interval: 1.11 to 1.36, p &lt; 0.001). The relationship between heart rate and outcomes was similar across LVEF categories and was not influenced by beta-blocker use (p value for interaction &gt;0.10 for both endpoints). However, amongst patients in AF at baseline, heart rate had no predictive value (p value for interaction &lt;0.001).</AbstractText>Resting heart rate is an important predictor of outcome in patients with stable chronic HF without AF, regardless of LVEF or beta-blocker use.</AbstractText>Copyright &#xa9; 2012 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.</CopyrightInformation>
14,140
Ventricular arrhythmias in the absence of structural heart disease.
Ventricular arrhythmia (VA) in structurally normal hearts can be broadly considered under non-life-threatening monomorphic and life-threatening polymorphic rhythms. Monomorphic VA is classified on the basis of site of origin in the heart, and the most common areas are the ventricular outflow tracts and left ventricular fascicles. The morphology of the QRS complexes on electrocardiogram is an excellent tool to identify the site of origin of the rhythm. Although these arrhythmias are common and generally carry an excellent prognosis, rare sudden death events have been reported. Very frequent ventricular ectopy may also result in a cardiomyopathy in a minority of patients. Suppression of VA may be achieved using calcium-channel blockers, beta-adrenergic blockers, and class I or III antiarrhythmic drugs. Radiofrequency ablation has emerged as an excellent option to eliminate these arrhythmias, although certain foci including aortic cusps and epicardium may be technically challenging. Polymorphic ventricular tachycardia (VT) is rare and generally occurs in patients with genetic ion channel disorders including long QT syndrome, Brugada syndrome, catecholaminergic polymorphic VT, and short QT syndrome. Unlike monomorphic VT, these arrhythmic syndromes are associated with sudden death. While the cardiac gross morphology is normal, suggesting a structurally normal heart, abnormalities exist at the molecular level and predispose them to arrhythmias. Another fascinating area, idiopathic ventricular fibrillation and early repolarization syndrome, are undergoing research for a genetic basis.
14,141
Use of rate control medication before cardioversion of recent-onset atrial fibrillation or flutter in the emergency department is associated with reduced success rates.
It is believed that when patients present to the emergency department (ED) with recent-onset atrial fibrillation or flutter (RAFF), controlling the ventricular rate before cardioversion improves the success rate. We evaluated the influence of rate control medication and other variables on the success of cardioversion.</AbstractText>This secondary analysis of a medical records review comprised 1,068 patients with RAFF who presented to eight Canadian EDs over 12 months. Univariate analysis was performed to find associations between predictors of conversion to sinus rhythm including use of rate control, rhythm control, and other variables. Predictive variables were incorporated into the multivariate model to calculate adjusted odds ratios (ORs) associated with successful cardioversion.</AbstractText>A total of 634 patients underwent attempted cardioversion: 428 electrical, 354 chemical, and 148 both. Adjusted ORs for factors associated with successful electrical cardioversion were use of rate control medication, 0.39 (95% confidence interval [CI] 0.21-0.74); rhythm control medication, 0.28 (95% CI 0.15-0.53); and CHADS&#x2082; score &gt; 0, 0.43 (95% CI 0.15-0.83). ORs for factors associated with successful chemical cardioversion were use of rate control medication, 1.29 (95% CI 0.82-2.03); female sex, 2.37 (95% CI 1.50-3.72); and use of procainamide, 2.32 (95% CI 1.43-3.74).</AbstractText>We demonstrated reduced successful electrical cardioversion of RAFF when patients were pretreated with either rate or rhythm control medication. Although rate control medication was not associated with increased success of chemical cardioversion, use of procainamide was. Slowing the ventricular rate prior to cardioversion should be avoided.</AbstractText>
14,142
Correlation between left atrial volume index and pulmonary artery pressure in patients with chronic severe mitral regurgitation.
Left atrial dilatation is a response to volume overload in chronic mitral regurgitation (MR). Left atrium volume index (LAVI) was associated with mortality, heart failure and atrial fibrillation in patients with MR. The authors do not know the association between LAVI and pulmonary artery pressure in patients with chronic severe primary MR.</AbstractText>The authors retrospectively studied patients with chronic severe MR (either one or both echocardiographic criteria of effective regurgitant orifice area &gt; or = 40 mm2 or regurgitant volume &gt; or = 60 ml by proximal isovelocity surface area method) who underwent transthoracic echocardiography at Siriraj Hospital between January 2005 and December 2009.</AbstractText>A total of 181 patients (age 53.1 +/- 17.7 years, 53.6% male) were enrolled. Right ventricular systolic pressure (RVSP) tended to increase when LAVI increased (r(s) = 0.32, p &lt; 0.001). The mean RVSP in 4 different quartiles of LAVI (&lt; or = 48.80 ml/ m2, 48.81-66.00 ml/m2, 66.01-97.40 ml/m2, &gt; 97.40 ml/m2) were 41 +/- 14, 42 +/- 16, 44 +/- 16 and 56 +/-18 mmHg, respectively RVSP in patients with LAVI &gt; 97.40 ml/m2 was significantly higher than those of the other 3 quartiles (p = 0.004). LAVI in patients with RVSP &lt; or = 50 and &gt; 50 mmHg were 74 +/- 53 and 116 +/- 82 ml/m2, respectively (p = 0.001).</AbstractText>In chronic severe primary MR, RVSP tends to increase when LAVI increases.</AbstractText>
14,143
Effect of spironolactone on ventricular arrhythmias in patients with left ventricular systolic dysfunction and implantable cardioverter defibrillators.
<AbstractText Label="AIMS/OBJECTIVES" NlmCategory="OBJECTIVE">Patients with implantable cardioverter defibrillators (ICD) often receive an adjunctive anti-arrhythmic therapy. We propose that an addition of spironolactone will reduce the number of clinically significant ventricular arrhythmias and ICD-related therapies.</AbstractText>In a multicentre retrospective study, 64 patients with ischaemic and non-ischaemic dilated cardiomyopathy whose left ventricular ejection fraction (LVEF) was &lt;35% and with ICD were selected. Amongst these patients, 28 patients were on spironolactone and 36 were not taking spironolactone. The ICD interrogation data were analysed for a maximum of 12 months. Wilcoxon Rank Sum test was used to compare the study and control groups. The outcomes were: (1) the number of shocks/anti-tachycardia pacing (ATP) episodes and (2) the number of episodes of ventricular tachycardia (VT) requiring ATP, non-sustained VT (NSVT), and ventricular fibrillation (VF) over the study period. The spironolactone group had fewer monthly, VTs (P=0.027) (requiring ATP). The two groups did not differ in the number of NSVT or VF per month.</AbstractText>Addition of spironolactone as an adjunct to ICD therapy in patients with congestive heart failure (CHF) reduces VT requiring ATP, but does not affect NSVT or VF per month.</AbstractText>Copyright &#xa9; 2012 Cardiological Society of India. Published by Elsevier B.V. All rights reserved.</CopyrightInformation>
14,144
Importance of the underlying substrate in determining thrombus location in atrial fibrillation: implications for left atrial appendage closure.
The left atrial appendage (LAA) has been suggested to be the dominant location of thrombus in atrial fibrillation (AF) and has led to the development of LAA occlusion as a therapeutic modality to reduce stroke risk. However, the patient populations that would benefit most from this therapy are not well defined.</AbstractText>A systematic review was performed to better define subgroups amenable to appendage closure.</AbstractText>The English scientific literature was searched using Pubmed through to March 1, 2011. Reference lists of relevant and review articles were screened to retrieve additional articles.</AbstractText>Studies were only included if they described the location of thrombus in left atrium. Case reports and case series describing less than 10 thrombi were excluded.</AbstractText>Two reviewers independently extracted data and assessed quality of each study.</AbstractText>A total of 34 studies reporting on the location of atrial thrombus in patients with AF were included: 17 in valvular AF, 10 non-valvular AF and 8 in mixed valvular and non-valvular AF. Atrial thrombi were located outside the LAA in 56% (95% CI 53, 60) of valvular AF, 22% (95% CI 19, 25) in mixed cohorts and 11% (95% CI 6, 15) non-valvular AF. In non valvular AF, the studies with higher proportion of thrombi in the left atrial cavity had non-anticoagulated patients and a greater proportion of ventricular dysfunction and history of stroke.</AbstractText>The location of atrial thrombus in patients with AF is dependent on the underlying substrate. In valvular AF, more than half the thrombi are located in the left atrial cavity. In the non-valvular AF group, a smaller proportion of thrombi were located outside the appendage. However, in certain subgroups (ie. non anti-coagulated, left ventricular dysfunction or prior stroke) the chances of left atrial cavity thrombus are higher.</AbstractText>
14,145
Upregulation of CaMKII&#x3b4; during ischaemia-reperfusion is associated with reperfusion-induced arrhythmias and mechanical dysfunction of the rat heart: involvement of sarcolemmal Ca2+-cycling proteins.
Although Ca(2+)/calmodulin-dependent protein kinase II delta (CaMKII&#x3b4;) has been implicated in development of different phenotypes of myocardial ischaemia-reperfusion injury, its involvement in arrhythmogenesis and cardiac stunning is not sufficiently elucidated. Moreover, the mechanisms by which CaMKII&#x3b4; mediates disturbances in excitation-contraction coupling, are not exactly known. To investigate this, KN-93 (0.5 &#xb5;mol/L), a CaMKII inhibitor, was administered before induction of global ischaemia and reperfusion in isolated Langendorff-perfused rat hearts. Expression of CaMKII&#x3b4; and the sarcollemal Ca(2+)-cycling proteins, known to be activated during reperfusion, was analyzed using immunoblotting. KN-93 reduced reperfusion-induced ectopic activity and the incidence of ventricular fibrillation. Likewise, the severity of arrhythmias was lower in KN-treated hearts. During the pre-ischaemia phase, neither inotropic nor chronotropic effects were elicited by KN-93, whereas post-ischaemic contractile recovery was significantly improved. Ischaemia-reperfusion increased the expression of CaMKII&#x3b4; and sodium-calcium exchanger (NCX1) proteins without any influence on the protein content of alpha 1c, a pore-forming subunit of L-type calcium channels (LTCCs). On the other hand, inhibition of CaMKII normalized changes in the expression of CaMKII&#x3b4; and NCX1. Taken together, CaMKII&#x3b4; seems to regulate its own turnover and to be an important component of cascade integrating NCX1, rather than LTCCs that promote ischaemia-reperfusion-induced contractile dysfunction and arrhythmias.
14,146
[The analysis of ECG of different state based on approximate entropy].
In this study, ECG signals of normal sinus rhythm (NSR), ventricular tachycardia (VT) and ventricular fibrillation (VF) were taken out to extract the RR interval series. Approximate entropy (ApEn) values of the RR interval series were calculated and compared among the three groups by ANOVA methods. It was found that the values of ApEn were increased significantly from NSR to VT and then to VF. Approximate entropy may be regarded as an index to discriminate the ECG signals of different state.
14,147
[The results of off-pump coronary artery bypass grafting for patients with malignant disease].
We performed off-pump coronary artery bypass grafting (OPCAB) operations in 95 patients between April 2007 and September 2010, 6 of whom had malignant disease. The malignancies were multiple myeloma (1 patient), malignant lymphoma (1 patient), lung cancer (1 patient), breast cancer (1 patient), stomach cancer (1 patient), and liver cancer (1 patient). The mean number of distal anastomoses was 5. The mean length of postoperative intensive care unit (ICU) stay was 3.7 days, and postoperative hospital stay was 20.0 days. There was no hospital death, but we experienced uncontrollable ventricular tachycardia (VT) and ventricular fibrillation (VF) in the case of multiple myeloma. He was treated by implantation of implantable cardioverter defibrillator (ICD) before discharge. All cases underwent treatment of malignancies early after OPCAB except liver cancer case. Because the patient was diagnosed with liver cancer just before the OPCAB, he was examined on cancer after OPCAB. We conclude that OPCAB is safety performed in a patient with malignant diseaes.
14,148
[Forensic medical diagnostics of chronic narcotic intoxication based on the morphological findings].
The objective of the present work was to develop the forensic medical criteria for chronic narcotic intoxication based on the results of morphological studies. The internal organs from 179 cadavers were available for the examination following death from acute poisoning with narcotic substances or as a result of chronic narcotic intoxication. The studies were carried out with the use of routine histological staining techniques and an immunohistological method. The data obtained provided a basis for the development of criteria to be employed in forensic medical diagnostics of acute poisoning with narcotic drugs and chronic narcotic intoxication. These criteria include ischemia of cerebral neurons, pulmonary emphysema with the formation of foreign body-type granulomas and fibrin/erythrocyte thrombi, morphological signs of ventricular fibrillation, the picture of bacterial endocarditis, follicular hyperplasia of the lymphoid organs, chronic portal hepatitis, and nodular degeneration of the adrenal cortex associated with its atrophy.
14,149
[Assessment of risk factors of atrial fibrillation in patients with metabolic syndrome].
The aim of the work was to identify risk factors of atrial fibrillation (AF) in 151 patients with metabolic syndrome (MS, IDF 2005); 88 of them presented with the recurrent form of AE 63 had no arrhythmia. Practically all patients suffered from arterial hypertension. The groups were comparable in terms of age, concomitant disorders, AH duration, arterial pressure, and severity of chronic heart failure. Patients with permanent AF, hemodynamically significant heart disease, myocardial infarction with wave Q in the medical history, and cardiac aneurysm were excluded from the study. We evaluated anthropometric parameters, carbohydrate and lipid metabolism, daily albuminuria, results of echoCG, and insulin resistance. Patients with AF had worse anthropometric and metabolic parameters and more pronounced remodeling of myocardium with left ventricular diastolic dysfunction, insulin resistance, endothelial dysfunction, and renal lesions than patients with MS without AF Patients with MS having abdominal obesity and AH over 10 years, marked insulin resistance (IR index higher than 2.77), reduced HDL cholesterol level (below 1.1 mmol/l), left atrial dilation (end diastolic size &gt;43mm), albuminuria &gt;60 mg/d, waist circumference &gt;104 cm were at high risk of AF (prognostically unfavourable arrhythmia). It is concluded that dynamic observation of the above MS and echo-CG parameters, and albuminuria coupled to the adequate correction of insulin resistance, control of AH and dyslipidemia is important for the prevention of cardiac arrhythmia.
14,150
Mild functional ischemic mitral regurgitation following acute coronary syndrome: a retrospective study.
Ischemic mitral regurgitation is a frequent complication of acute coronary syndrome. It primarily occurs in patients with a prior myocardial infarction but also may be seen with acute ischemia, a setting in which the MR typically resolves after the ischemia resolves. The vast majority of patients have "functional" ischemic MR. In these individuals, the papillary muscles, chordae, and valve leaflets are normal. However, the leaflets do not coapt and restricted leaflet motion is frequently noted on echocardiography. Ischemic mitral regurgitation indicates a poor prognosis after acute myocardial infarction. This study addresses the clinical characteristics of patients of acute coronary syndrome with mild functional ischemic mitral regurgitation and its impact on immediate in-hospital cardiovascular outcomes and death.</AbstractText>From March 2006 through May 2007, patients who underwent 2-dimensional (2D) color doppler echocardiographic quantification of ischemic mitral regurgitation within 10 days of admission for acute coronary syndrome (ACS) in Manipal Teaching Hospital, a tertiary hospital in the western region of Nepal were noted. The demographic details, conventional risk factors of coronary artery disease, clinical and laboratory findings, treatment course and in-hospital outcomes of all the patients with mild functional ischemic MR following ACS in that time duration were recorded in a designated Performa. A total of 94 patients enrolled in the study were divided into two groups: Group I with mild functional ischemic MR and Group II without MR on 2D echocardigraphic assessment. Patient characteristics, risk factors, ejection fraction, and cardiovascular outcome and death among the two groups were compared and analyzed using software package SPSS 17.0 version.</AbstractText>Group I constituted 64.89% of the study population and Group II comprised of 35.11%. The patients in Group I was more likely to be elderly diabetic (P&lt;0.05), and smokers with hypertension (P &lt; 0.05). Mild functional ischemic MR was more common in patients with STEMI as compared to those with unstable angina and NSTEMI (55.7%, 36.1%, and 8.2%; P &lt; 0.05).The mean ejection fraction in the first group was 54.84% in contrast to 58.92% observed in group II (P &lt; 0.05).The type of wall involvement inferred from EKG analysis was homogeneously distributed in both the groups. Finally, there was no difference in immediate in-hospital (within 10 days) mortality or cardiovascular outcomes (heart failure, ventricular tachycardia/fibrillation, hypotension, and cardiogenic shock) between these two groups.</AbstractText>Ischemic mitral regurgitation following acute coronary syndromeare more likely in elderly diabetics and hypertensive smokers. It is a more common finding in STEMI. Although mild MR following ACS does reduce ejection fraction, the immediate (within 10 days) in-hospital mortality and cardiovascular outcomes are not significantly altered.</AbstractText>
14,151
Hemodynamic findings in severe tricuspid regurgitation.
Tricuspid regurgitation (TR) most commonly occurs in response to right ventricular (RV) dilation with structural abnormalities in the tricuspid valve being rarer. In addition to RV size and valvular integrity, the amount of TR is influenced by RV preload and afterload, the respiratory cycle, left heart function and atrial fibrillation. Hemodynamic changes in right atrial (RA) pressures in severe TR include elevated mean pressures, a large systolic wave called an "s" wave, a prominent 'Y' descent and a blunted 'X' descent. In addition, RV end diastolic pressure is elevated and cardiac output is reduced, especially with exercise. "Ventricularization" of the RA pressure tracing, in which the contour of the RA pressure is similar to, but of lower amplitude than, the contour of the RV pressure is the most specific finding but is found in a minority of patients with severe TR. In summary, alterations in the RA pressure tracing are common in patients with severe TR but specific hemodynamic findings lack sensitivity, which may in part be due to the large effects of RV preload, RV afterload and RA compliance on the amount of TR.
14,152
Successful percutaneous coronary intervention in a case of acute aortic dissection complicated with malperfusion of the left main coronary artery after replacement of the ascending aorta.
A 75-year-old female was admitted to our hospital with sudden back pain and right leg ischemia. Computed tomography showed acute type A aortic dissection with the occlusion of the right common iliac artery. The patient was treated with ascending aorta replacement and femoro-femoral bypass. Three hours after the operation, the patient went into a sudden shock. Electrocardiogram showed ventricular tachycardia and ventricular fibrillation. Percutaneous cardio-pulmonary support was administered and coronary arteriogram (CAG) was proceeded for evaluation of the coronary arteries. Although CAG revealed normal coronary arteries, intravascular ultrasound showed mobile intimal flap at left main coronary artery trunk, suggesting dissection of the coronary artery. Percutaneous coronary intervention of the left main coronary artery trunk was performed. The patient recovered from shock and was discharged from the hospital without any major complication.
14,153
Marine omega-3 fatty acids and coronary heart disease.
To provide an overview of the key earlier intervention studies with marine omega-3 fatty acids and to review and comment on recent studies reporting on mortality outcomes and on selected underlying mechanisms of action.</AbstractText>Studies relating marine omega-3 fatty acid status to current or future outcomes continue to indicate benefits, for example, on incident heart failure, congestive heart failure, acute coronary syndrome, and all-cause mortality. New mechanistic insights into the actions of marine omega-3 fatty acids have been gained. Three fairly large secondary prevention trials have not confirmed the previously reported benefit of marine omega-3 fatty acids towards mortality in survivors of myocardial infarction. Studies of marine omega-3 fatty acids in atrial fibrillation and in cardiac surgery-induced atrial fibrillation have produced inconsistent findings and meta-analyses demonstrate no benefit. A study confirmed that marine omega-3 fatty acids reduce the inflammatory burden with advanced atherosclerotic plaques, so inducing greater stability.</AbstractText>Recent studies of marine omega-3 fatty acids on morbidity of, and mortality from, coronary and cardiovascular disease have produced mixed findings. These studies raise new issues to be addressed in future research.</AbstractText>
14,154
A case of sudden infant death due to a primary cardiac sarcoma.
The case reported herein concerns the unexpected death of a 3-month-old female newborn who suddenly collapsed in her mother's arms and was dead on arrival at the hospital. The clinical histories of the baby and her parents were negative for symptoms or signs of illness, even those of cardiovascular origin. Furthermore, no clinical appearance of a pathologic status was noted by pediatricians after the birth until the last emergency recovery. The autopsy excluded external and internal signs of violence but revealed a large primary cardiac tumor arising from the free wall of the left ventricle, which had totally invaded the heart causing mitral valve deformation. Histological examination showed a low-grade sarcoma that completely infiltrated the myocardial tissue. The pathogenesis of this sudden infant death was postulated as being owing to a fatal ventricular fibrillation combined with a tumor-related restrictive cardiomyopathy obstructing left ventricular filling.
14,155
Safety and efficacy of intracoronary adenosine administration in patients with acute myocardial infarction undergoing primary percutaneous coronary intervention: a meta-analysis of randomized controlled trials.
Studies evaluating intracoronary administration of adenosine for prevention of microvascular dysfunction and ischemic-reperfusion injury in patients with acute myocardial infarction (AMI) undergoing primary percutaneous coronary intervention (PCI) have yielded mixed results. Therefore, we performed a meta-analysis of these trials to evaluate the safety and efficacy of intracoronary adenosine administration in patients with AMI undergoing primary PCI.</AbstractText>A total of seven prospective randomized controlled trials were analyzed. The endpoints extracted were post-procedure residual stent thrombosis (ST) segment elevation and ST segment resolutions (STRes), difference in peak creatine kinase (CK-MB) concentration, thrombolysis in myocardial infarction (TIMI) grade III flow (TIMI 3 flow), myocardial blush grade (MBG) 3, mean difference in post-PCI ejection fraction (EF), all-cause mortality, cardiovascular mortality, heart failure (HF) and major adverse cardiovascular event (MACE). Safety endpoints analyzed were bradycardia, second-degree atrioventricular block (AVB), ventricular tachycardia (VT), ventricular fibrillation (VF) and recurrence of chest pain (CP). The endpoints were analyzed by standard methods of meta-analysis.</AbstractText>Intracoronary adenosine therapy led to significantly more post-PCI STRes [relative risk (RR) 1.39, 95% confidence interval (CI) 1.01-1.90; p = 0.04] and reduction in residual ST segment elevation (RR 0.82, CI 0.69-0.99; p = 0.04) but did not improve TIMI 3 flow (RR 1.09, CI 0.94-1.27; p = 0.25), MBG3 (RR 1.04, CI 0.65-1.69; p = 0.88), peak CK-MB concentration (mean difference -39.43, CI -120.223 to 41.371; p = 0.339) and post-PCI EF (mean difference 1.238, CI -5.802 to 8.277; p = 0.730). There was a trend towards improvement and MACE (RR 0.64, CI 0.40-1.03; p = 0.06), incidence of HF (RR 0.47, CI 0.19-1.12; p = 0.08) and CV mortality (RR 0.15, CI 0.02-1.23; p = 0.08) that did not reach statistical significance but no difference in all-cause mortality (RR 0.77, CI 0.25-2.34; p = 0.64). Safety analysis showed no significant difference in CP events (RR 1.26, CI 0.55-2.86; p = 0.58), bradycardia (RR 2.19, CI 0.24-0.38; p = 0.49), VT (odds ratio 0.61, CI 0.08-4.90; p = 0.64) and VF (RR 0.49, CI 0.13-1.90; p = 0.30), but significantly more second-degree AVB (RR 7.88, CI 4.15-14.9; p &lt; 0.01) in the adenosine group compared with the placebo group.</AbstractText>Intracoronary adenosine administration was well tolerated and significantly improved electrocardiographic outcomes with a tendency towards improvement in MACE, HF and CV mortality that could not reach statistical significance.</AbstractText>
14,156
A KCNJ8 mutation associated with early repolarization and atrial fibrillation.
The Kir 6.1 K(atp) channel is believed to play an important role in ventricular repolarization as determined from both functional and genetic studies of the potassium inwardly-rectifying channel, subfamily J, member 8 (KCNJ8)-S422L missense mutation in patients with J-wave syndromes. Although Kir6.1 is also present in atrial tissue, it is unknown whether this channel modulates atrial repolarization and hence whether the S422L mutation portends a greater risk of atrial arrhythmias. This study sought to examine whether there was an increased frequency of the KCNJ8-S422L mutation among patients with atrial fibrillation (AF) and early repolarization (ER) as a possible novel susceptibility gene for AF.</AbstractText>A total of 325 lone AF probands were identified from the Vanderbilt AF Registry, a collection of clinical data and DNA from consented, consecutively enrolled participants. The coding regions of KCNJ8 were sequenced, and the patient's presenting electrocardiogram (ECG) was reviewed by two independent physicians for ER abnormalities. The KCNJ8-S422L mutation was identified in two AF probands while no other candidate gene variants were identified in these cases. Twenty-two (7%) patients were found to have ER on the ECG, including the two probands carrying the S422L variant. In one small AF kindred, the S422L variant co-segregated with AF and ER.</AbstractText>The KCNJ8-S422L variant is associated with both increased AF susceptibility and ER indicating a role for Kir 6.1 K(atp) channel in both ventricular and atrial repolarization.</AbstractText>
14,157
Correlation between coronary perfusion pressure and quantitative ECG waveform measures during resuscitation of prolonged ventricular fibrillation.
The ventricular fibrillation (VF) waveform is dynamic and predicts defibrillation success. Quantitative waveform measures (QWMs) quantify these changes. Coronary perfusion pressure (CPP), a surrogate for myocardial perfusion, also predicts defibrillation success. The relationship between QWM and CPP has been preliminarily explored. We sought to further delineate this relationship in our porcine model and to determine if it is different between animals with/without ROSC (return of spontaneous circulation).</AbstractText>A relationship exists between QWM and CPP that is different between animals with/without ROSC.</AbstractText>Utilizing a prior experiment in our porcine model of prolonged out-of-hospital VF cardiac arrest, we calculated mean CPP, cumulative dose CPP, and percent recovery of three QWM during resuscitation before the first defibrillation: amplitude spectrum area (AMSA), median slope (MS), and logarithm of the absolute correlations (LAC). A random effects linear regression model with an interaction term CPP ROSC investigated the association between CPP and percent recovery QWM and how this relationship changes with/without ROSC.</AbstractText>For 12 animals, CPP and QWM measures (except LAC) improved during resuscitation. A linear relationship existed between CPP and percent recovery AMSA (coefficient 0.27; 95%CI 0.23, 0.31; p&lt;0.001) and percent recovery MS (coefficient 0.80; 95%CI 0.70, 0.90; p&lt;0.001). A linear relationship existed between cumulative dose CPP and percent recovery AMSA (coefficient 2.29; 95%CI 2.0, 2.56; p&lt;0.001) and percent recovery MS (coefficient 6.68; 95%CI 6.09, 7.26; p&lt;0.001). Animals with ROSC had a significantly "steeper" dose-response relationship.</AbstractText>There is a linear relationship between QWM and CPP during chest compressions in our porcine cardiac arrest model that is different between animals with/without ROSC.</AbstractText>Copyright &#xa9; 2012 Elsevier Ireland Ltd. All rights reserved.</CopyrightInformation>
14,158
Morphological abnormalities in baseline ECGs in healthy normal volunteers participating in phase I studies.
<AbstractText Label="BACKGROUND &amp; OBJECTIVES" NlmCategory="OBJECTIVE">Morphological abnormalities in 12-lead electrocardiograms (ECGs) are seen in subgroups of healthy individuals like athletes and air-force personnel. As these populations may not truly represent healthy individuals, we assessed morphological abnormalities in ECG in healthy volunteers participating in phase I studies, who are screened to exclude associated conditions.</AbstractText>ECGs from 62 phase I studies analyzed in a central ECG laboratory were pooled. A single drug-free baseline ECG from each subject was reviewed by experienced cardiologists. ECG intervals were measured on five consecutive beats and morphological abnormalities identified using standard guidelines.</AbstractText>Morphological abnormalities were detected in 25.5 per cent of 3978 healthy volunteers (2495 males, 1483 females; aged 18-76 yr); the presence was higher in males (29.3% vs. 19.2% in females; P&lt;0.001). Rhythm abnormalities were the commonest (11.5%) followed by conduction abnormalities (5.9%), axis deviation (4%), ST-T wave changes (3.1%) and chamber enlargement (1.4%). Incomplete right bundle branch block (RBBB), short PR interval and right ventricular hypertrophy were common in young subjects (&lt;20 yr) while atrial fibrillation, first degree atrioventricular block, complete RBBB and left anterior fascicular block were more prevalent in elderly subjects (&gt;65 yr). Prolonged PR interval, RBBB and intraventricular conduction defects were more common in males while sinus tachycardia, short PR interval and non-specific T wave changes were more frequent in females.</AbstractText><AbstractText Label="INTERPRETATION &amp; CONCLUSIONS" NlmCategory="CONCLUSIONS">Morphological abnormalities in ECG are commonly seen in healthy volunteers participating in phase I studies; and vary with age and gender. Further studies are required to determine whether these abnormalities persist or if some of these disappear on follow up.</AbstractText>
14,159
Arrhythmia discrimination using hemoglobin spectroscopy in humans.
Inappropriate therapies are frequently delivered by implantable cardioverter-defibrillators (ICDs). We have investigated muscle perfusion as a means of augmenting arrhythmia discrimination by using implanted near-infrared spectroscopy.</AbstractText>To evaluate hemodynamic stability by monitoring muscle perfusion from within the ICD pocket, in fresh tissue and inside the scar capsule on preexisting ICD generators, during induced cardiac arrhythmias, in humans.</AbstractText>The sensor was implanted on or under the pectoral muscle, during ICD defibrillation threshold testing. A microvascular oxygenation trend indicator (O2 Index) was computed during 74 induced ventricular fibrillation and 34 normal sinus rhythm episodes in 34 patients and also during 28 atrial and 90 ventricular overdrive pacing episodes as simulations of supraventricular and ventricular tachycardias, respectively.</AbstractText>On average, the change in oxygenation, based on the O2 Index, was statistically significant (P &lt;.003) from baseline within 3 seconds following cardiac arrest. An optimized O2 Index, used for detecting the hemodynamic trend, exhibited a decreasing trend during ventricular fibrillation (P &lt;.0001) and was different from that during normal sinus rhythm (P &lt;.0001). The sensitivity for the detection of ventricular fibrillation was 100%, and the specificity for the rejection of normal sinus rhythm was 82% in the presence of scar tissue on the optical sensor. For a 35-mm Hg drop in the mean arterial pressure as the threshold for hemodynamic instability, the specificity for the rejection of hemodynamically stable atrial and ventricular pacing episodes was 93% and 71%, respectively.</AbstractText>An implantable near-infrared spectroscopic sensor may be useful for hemodynamic monitoring during cardiac arrhythmias to prevent inappropriate therapy.</AbstractText>Copyright &#xa9; 2012 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.</CopyrightInformation>
14,160
Engaging a whole community in resuscitation.
Survival after out-of-hospital cardiac arrest (OHCA) is influenced by each link in the chain of survival. On the Danish island of Bornholm (population 42,000, area 588 km2) none survived an OHCA in 2001-2003. Therefore, we designed a multifaceted community-based approach aiming at strengthening each link in the chain of survival. The purpose of this study was to evaluate the effect of implementation of the intervention on bystander basic life support (BLS) rates and survival to hospital discharge after OHCA.</AbstractText>Laypersons completed 24-min DVD-based-self-instruction BLS courses in schools and workplaces or 4-h BLS/automated external defibrillator (AED) courses. The local television station had broadcasts about resuscitation. The ambulance personnel were trained and the staff at the island hospital completed BLS courses or more advanced courses.</AbstractText>During 2 years 9226 people (22% of the population) completed the short course and 2453 (6% of the population) completed the 4-h course. The number of AEDs increased from 3 to 147. The bystander BLS rate for OHCAs with a presumed cardiac aetiology (N=96, incidence 114/100,000 person-years) was 47% [95% CI 30-50] and for witnessed OHCAs (N=35) it increased significantly from 22% (2004) to 74% [95% CI 58-86]. The AEDs were deployed in 9 cases. Survival to discharge for all-rhythms OHCA was 5.4% [95% CI 2-12], and for witnessed ventricular fibrillation (N=17) 18% [95% CI 5-42].</AbstractText>Strengthening all links in the chain of survival was associated with significant increases in bystander BLS rates and survival after OHCA on a rural island.</AbstractText>Copyright &#xa9; 2012 Elsevier Ireland Ltd. All rights reserved.</CopyrightInformation>
14,161
Spatiotemporally controlled cardiac conduction block using high-frequency electrical stimulation.
Methods for the electrical inhibition of cardiac excitation have long been sought to control excitability and conduction, but to date remain largely impractical. High-amplitude alternating current (AC) stimulation has been known to extend cardiac action potentials (APs), and has been recently exploited to terminate reentrant arrhythmias by producing reversible conduction blocks. Yet, low-amplitude currents at similar frequencies have been shown to entrain cardiac tissues by generation of repetitive APs, leading in some cases to ventricular fibrillation and hemodynamic collapse in vivo. Therefore, an inhibition method that does not lead to entrainment - irrespective of the stimulation amplitude (bound to fluctuate in an in vivo setting) - is highly desirable.</AbstractText><AbstractText Label="METHODOLOGY/PRINCIPAL FINDINGS" NlmCategory="RESULTS">We investigated the effects of broader amplitude and frequency ranges on the inhibitory effects of extracellular AC stimulation on HL-1 cardiomyocytes cultured on microelectrode arrays, using both sinusoidal and square waveforms. Our results indicate that, at sufficiently high frequencies, cardiac tissue exhibits a binary response to stimulus amplitude with either prolonged APs or no effect, thereby effectively avoiding the risks of entrainment by repetitive firing observed at lower frequencies. We further demonstrate the ability to precisely define reversible local conduction blocks in beating cultures without influencing the propagation activity in non-blocked areas. The conduction blocks were spatiotemporally controlled by electrode geometry and stimuli duration, respectively, and sustainable for long durations (300 s).</AbstractText><AbstractText Label="CONCLUSION/SIGNIFICANCE" NlmCategory="CONCLUSIONS">Inhibition of cardiac excitation induced by high-frequency AC stimulation exhibits a binary response to amplitude above a threshold frequency, enabling the generation of reversible conduction blocks without the risks of entrainment. This inhibition method could yield novel approaches for arrhythmia modeling in vitro, as well as safer and more efficacious tools for in vivo cardiac mapping and radio-frequency ablation guidance applications.</AbstractText>
14,162
Spinal cord stimulation protects against atrial fibrillation induced by tachypacing.
Spinal cord stimulation (SCS) has been shown to modulate atrial electrophysiology and confer protection against ischemia and ventricular arrhythmias in animal models.</AbstractText>To determine whether SCS reduces the susceptibility to atrial fibrillation (AF) induced by tachypacing (TP).</AbstractText>In 21 canines, upper thoracic SCS systems and custom cardiac pacing systems were implanted. Right atrial and left atrial effective refractory periods were measured at baseline and after 15 minutes of SCS. Following recovery in a subset of canines, pacemakers were turned on to induce AF by alternately delivering TP and searching for AF. Canines were randomized to no SCS therapy (CTL) or intermittent SCS therapy on the initiation of TP (EARLY) or after 8 weeks of TP (LATE). AF burden (percent AF relative to total sense time) and AF inducibility (percentage of TP periods resulting in AF) were monitored weekly. After 15 weeks, echocardiography and histology were performed.</AbstractText>Effective refractory periods increased by 21 &#xb1; 14 ms (P = .001) in the left atrium and 29 &#xb1; 12 ms (P = .002) in the right atrium after acute SCS. AF burden was reduced for 11 weeks in EARLY compared with CTL (P &lt;.05) animals. AF inducibility remained lower by week 15 in EARLY compared with CTL animals (32% &#xb1; 10% vs 91% &#xb1; 6%; P &lt;.05). AF burden and inducibility were not significantly different between LATE and CTL animals. There were no structural differences among any groups.</AbstractText>SCS prolonged atrial effective refractory periods and reduced AF burden and inducibility in a canine AF model induced by TP. These data suggest that SCS may represent a treatment option for AF.</AbstractText>Copyright &#xa9; 2012 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.</CopyrightInformation>
14,163
Subcutaneous implantable cardioverter defibrillator in a patient with pectus excavatum.
Sudden cardiac arrest in young healthy adults has concerned the medical and social communities due to its fatal effect. Implantable cardioverter defibrillator (ICD) has been demonstrated to be an effective measure for prevention of sudden death in patients at risk of ventricular arrhythmia. Subcutaneous ICD has been developed to overcome some problems associated with transvenous leads in the conventional ICD. In this case report, we describe the use of completely subcutaneous ICD for a young patient with pectus excavatum following presentation with out-of-hospital VF arrest with no complication in device or lead positioning.
14,164
[Basic cardiopulmonary resuscitation: knowledge, practical skills and effectiveness of maneuvers of general physicians].
General physicians should be adequately trained to deliver effective resuscitation during ventricular fibrillation (VF).</AbstractText>To assess the degree of knowledge, skills and practical effectiveness in cardiopulmonary resuscitation (CPR) of Chilean general physicians.</AbstractText>Forty eight general physicians starting Anesthesiology or Internal Medicine residency programs were evaluated. They answered a modified American Heart Association Basic Life Support Course written test and individually participated in a witnessed VF cardiac arrest simulated scenario. Execution of resuscitation tasks in the correct order, the quality of the maneuvers and the use of defibrillator were registered.</AbstractText>All participants acknowledged the importance of uninterrupted CPR and early defibrillation. Seventy five percent knew the correct frequency of chest compressions, but only 6.25% knew all the effective chest compression characteristics. Ninety eight percent knew the recommended number of breaths per cycle. In practice, 58% performed effective ventilations, 33% performed uninterrupted compressions, 14% did them with adequate frequency and only 8% performed chest compressions adequately. Forty four percent requested a defibrillator within 30 seconds and 31% delivered the first defibrillation within 30 seconds of defibrillator arrival. Airway, breathing, circulation and defibrillation sequence was correctly performed by 12% of participants and 80% acknowledged that their medical training was inadequate or insufficient for managing a cardiac arrest.</AbstractText>Despite an elevated degree of knowledge about key aspects of CPR, this group of Chilean physicians displayed suboptimal practical skills while performing CPR in a simulated scenario, specially delivering effective chest compressions and promptly asking for and using the defibrillator.</AbstractText>
14,165
Serum amyloid a and C-reactive protein independently predict the recurrences of atrial fibrillation after cardioversion in patients with preserved left ventricular function.
Subclinical inflammation and atrial stretch have been recognized as important contributors to atrial fibrillation (AF) onset and perpetuation. The aim of the study was to compare the predictive role of serum inflammatory markers (serum amyloid A [SAA], and C-reactive protein [CRP]) and N-terminal pro brain natriuretic peptide (NT-proBNP) an indice of atrial strain in relation to subacute arrhythmic recurrence rate in patients with persistent AF and normal left ventricular ejection fraction (LVEF).</AbstractText>We studied 57 patients with a mean LVEF of 58.7 &#xb1; 6%. NT-proBNP, SAA and CRP levels were determined few hours before electrical cardioversion and 3 weeks after cardioversion.</AbstractText>Subacute AF recurrences were documented in 19 (33 %) patients. Whereas NT-proBNP levels did not predict arrhythmic outcome, higher SAA (&gt; 6.16-6.19 mg/L) and CRP levels (&gt; 2.99-3.10 mg/L) were significantly associated with AF recurrences (odds ratio [OR], 5.39; 95% confidence interval [CI], 1.59-18.26; P = 0.007 and OR, 14.93; 95% CI, 3.90-57.19; P &lt; 0.001). Both SAA (OR, 18.29; 95% CI, 2.07-161.46; P = 0.009) and high sensitivity CRP (OR, 42.03; 95% CI, 4.83-365.45; P = 0.001) through the multivariate logistic regression analysis show an independent role in predicting the AF recurrence with a sensitivity of 100% (38/38) and a specificity of 52.6% (10/19).</AbstractText>The present study demonstrates that in patients with persistent AF and preserved LVEF, SAA and CRP levels are independent predictors of AF subacute recurrence rate, whereas NT-proBNP, not associated with arrhythmic outcome, reflects the hemodynamic alterations secondary to arrhythmia presence. The simultaneous determination of SAA and high sensitivity CRP has a very high sensitivity (100%) in predicting the AF recurrence.</AbstractText>Copyright &#xa9; 2012 Canadian Cardiovascular Society. Published by Elsevier Inc. All rights reserved.</CopyrightInformation>
14,166
Direct protective effects of dexmedetomidine against myocardial ischemia-reperfusion injury in anesthetized pigs.
Systemic administration of &#x3b1;2-adrenergic agonists has been shown to protect ischemic myocardium, but the direct effects on ischemia-reperfused myocardium have not yet been clarified. This study was carried out to determine the effects of intracoronary dexmedetomidine (DEX) on the myocardial ischemia-reperfusion injury in anesthetized pigs. In open-chest pigs, the left anterior descending coronary artery was perfused through an extracorporeal circuit from the carotid artery. They received intracoronary infusion of DEX at a rate of 1 ng &#xb7; mL(-1) (group LD, n = 9), 10 ng &#xb7; mL(-1) (group MD, n = 9), or 100 ng &#xb7; mL(-1) (group HD, n = 9) of coronary blood flow or vehicle (group C, n = 12) for 30 min before ischemia. Myocardial stunning was produced by 12-min ischemia of the perfused area of left anterior descending coronary artery and 90-min reperfusion. The effect on reperfusion-induced arrhythmias was evaluated using the incidence of ventricular tachycardia or fibrillation after reperfusion. Regional myocardial contractility was evaluated with segment shortening (%SS). Dexmedetomidine significantly reduced the incidence of reperfusion-induced ventricular arrhythmias. Dexmedetomidine significantly improved the recovery of percentage segment shortening at 90 min after reperfusion (32.6% &#xb1; 3.1% in group C, 58.2% &#xb1; 2.1% in group LD, 61.1% &#xb1; 1.8% in group MD, and 72.0% &#xb1; 2.0% in group HD). Dexmedetomidine suppressed the increase in plasma norepinephrine concentration after reperfusion. The results indicate that DEX would exert the protective effect against ischemia-reperfusion injury by the direct action on the myocardium, which is not mediated through the central nervous system.
14,167
Use of implantable cardioverter defibrillators in patients with left ventricular assist devices.
Patients with left ventricular assist devices (LVADs) are at high risk of sustained ventricular arrhythmias, but these may be remarkably well tolerated and the association with sudden death is unclear. Many patients who receive an LVAD already have an implantable cardioverter defibrillator (ICD). While it is standard practice to reactivate a previously implanted ICD in an LVAD recipient, this should include discussion of the revised risks and benefits of ICD therapy following LVAD implantation. In particular, patients should be warned that they might receive a significant number of ICD shocks that may not be life saving. When ICDs are reactivated, device programming should minimize the risk of repeated shocks for non-sustained or well-tolerated ventricular arrhythmias. Implantation of a primary prevention ICD after implantation of an LVAD is not supported by current evidence, poses potential risks, and should be the subject of a clinical trial before it becomes standard practice.
14,168
Sudden cardiac arrest and death following application of shocks from a TASER electronic control device.
The safety of electronic control devices (ECDs) has been questioned. The goal of this study was to analyze in detail cases of loss of consciousness associated with ECD deployment.</AbstractText>Eight cases of TASER X26 ECD-induced loss of consciousness were studied. In each instance, when available, police, medical, and emergency response records, ECD dataport interrogation, automated external defibrillator information, ECG strips, depositions, and autopsy results were analyzed. First recorded rhythms were ventricular tachycardia/fibrillation in 6 cases and asystole (after &#x2248; 30 minutes of nonresponsiveness) in 1 case. An external defibrillator reported a shockable rhythm in 1 case, but no recording was made. This report offers evidence detailing the mechanism by which an ECD can produce transthoracic stimulation resulting in cardiac electrical capture and ventricular arrhythmias leading to cardiac arrest.</AbstractText>ECD stimulation can cause cardiac electrical capture and provoke cardiac arrest resulting from ventricular tachycardia/ventricular fibrillation. After prolonged ventricular tachycardia/ventricular fibrillation without resuscitation, asystole develops.</AbstractText>
14,169
A multicentre, randomized study of telmisartan versus carvedilol for prevention of atrial fibrillation recurrence in hypertensive patients.
Atrial remodelling, leading to atrial fibrillation (AF), is mediated by the renin-angiotensin-aldosterone system.</AbstractText>Mild hypertensive outpatients (systolic/diastolic blood pressure 140-159/90-99 mmHg) in sinus rhythm who had experienced &#x2265; 1 electrocardiogram (ECG)-documented AF episode in the previous six months received randomly telmisartan 80 mg/day or carvedilol 25 mg/day. Blood pressure and 24-hour ECG were monitored monthly for one year; patients were asked to report symptomatic AF episodes and to undergo an ECG as early as possible.</AbstractText>One hundred and thirty-two patients completed the study (telmisartan, n=70; carvedilol, n=62). Significantly fewer AF episodes were reported with telmisartan versus carvedilol (14.3% vs. 37.1%; p&lt;0.003). Left atrial diameter, assessed by echocardiography, was similar with telmisartan and carvedilol (3.4&#xb1;2.3 cm vs. 3.6&#xb1;2.4 cm). At study end, both regimes significantly reduced mean left ventricular mass index, but the reduction obtained with telmisartan was significantly greater than with carvedilol (117.8&#xb1;10.7 vs. 124.7&#xb1;14.5; p&lt;0.0001). Mean blood pressure values were not significantly different between the groups (telmisartan 154/97 to 123/75 mmHg; p&lt;0.001; carvedilol 153/94 to 125/78 mmHg; p&lt;0.001).</AbstractText>Telmisartan was significantly more effective than carvedilol in preventing recurrent AF episodes in hypertensive AF patients, despite a similar lowering of blood pressure.</AbstractText>
14,170
Effectiveness of Public Access Defibrillation with AEDs for Out-of-Hospital Cardiac Arrests in Japan.
In Japan, about 60,000 out-of-hospital cardiac arrests of cardiac etiology occur annually. Early initiation of cardiopulmonary resuscitation (CPR) and early defibrillation with public access automated external defibrillators (AEDs) by bystanders is the key to increasing survival after an out-of-hospital cardiac arrest (OHCA). Japanese data shows that nationwide dissemination of public access AEDs actually increases the rate of survival with a good neurological outcome after OHCA. Recently, the number of public access AEDs has been increasing rapidly, but implementation of AED use and CPR by public bystanders has not been sufficiently frequent, despite having become more common than before. To improve the rate of OHCA survival with a good neurological outcome by making effective use of AEDs, there need to be further spread of AEDs with specific installation criteria as well as infrastructure development for promoting AED use. In addition, educational activities and practical programs should be introduced in the community setting. Recently, many reports, including by the Utstein Osaka Project, have showed that chest compression-only CPR is as effective as conventional CPR with rescue breathing. To save more lives, we should encourage the widespread practice of CPR by widely diffusing AEDs and simplified chest compression-only CPR training.
14,171
Comparison of cardiac stem cells and mesenchymal stem cells transplantation on the cardiac electrophysiology in rats with myocardial infarction.
Whether transplanted cardiac stem cells (CSCs) and mesenchymal stem cells (MSCs) improved ventricular fibrillation threshold (VFT) similarly is still unclear. We sought to compare the effects of the CSC and MSC transplantation on the electrophysiological characteristics and VFT in rats with myocardial infarction (MI).</AbstractText>MI was induced in 30 male Sprague-Dawley rats. Two weeks later, animals were randomized to receive 5&#x2009;&#xd7;&#x2009;10(6) CSCs labeled with PKH26 in PBS or 5&#x2009;&#xd7;&#x2009;10(6) MSCs labeled with PKH26 in phosphate buffer solution(PBS) or PBS alone injection into the infarcted anterior ventricular free wall. Six weeks after the injection, electrophysiological characteristics and VFT were measured. Labeled CSCs and MSCs were observed in 5&#xa0;&#x3bc;m cryostat sections from each heart.</AbstractText>Malignant ventricular arrhythmias were significantly (P&#x2009;=&#x2009;0.0055) less inducible in the CSC group than the MSC group. The VFTs were improved in the CSC group compared with the MSC group. Labeled CSCs and MSCs were identified in the infarct zone and infarct marginal zone. Labeled CSCs expressed Connexin-43, von Willebrand factor, &#x3b1;-smooth muscle actin and &#x3b1;-sarcomeric actin,while the Labeled MSCs expressed von Willebrand factor, &#x3b1;-smooth muscle actin and &#x3b1;-sarcomeric actin in vivo.</AbstractText>After 6&#xa0;weeks of cell transplantation, CSCs are superior to MSCs in modulating the electrophysiological abnormality and improving the VFT in rats with MI. CSCs and MSCs express markers that suggest muscle, endothelium and vascular smooth muscle phenotypes in vivo, but MSCs rarely express Connexin-43.</AbstractText>
14,172
[Video-assisted thoracoscopic removal of esophageal leiomyomas with intraoperative tumor location by endoscopy].
To summarize our experience with video-assisted thoracoscopic (VATS) removal of esophageal leiomyoma located with endoscopy during operation.</AbstractText>Between January 2006 and December 2010, 55 patients with esophageal leiomyoma underwent VATS enucleation. The surgical procedure was similar to that of open thoracotomy with intraoperative endoscopic location of the tumor and examination of the mucosal integrity especially for tumors less than 1 cm in diameter.</AbstractText>Of the 55 patients undergoing VATS tumor removal, 54 patients completed the procedures smoothly, and 1 patient experienced ventricular fibrillation during the operation to require an open thoracotomy. Endoscopy was used in 38 patients during the operation. VATS enucleation differed significantly from open thoracotomy in the volume of bleeding, postoperative fasting days and postoperative hospital stay (P&lt;0.05). The symptoms were completely relieved after the operation without postoperative complications. The patients were followed up for 8 to 59 months (mean 23.0 months) and no recurrence was found.</AbstractText>VATS removal of esophageal leiomyomas is minimally invasive, safe and effective and can serve as the primary option for surgical removal of esophageal leiomyomas.</AbstractText>
14,173
Acute effects of right ventricular apical pacing on left atrial remodeling and function.
The acute effects of right ventricular apical (RVA) pacing on left atrial (LA) function in patients with normal ejection fraction are not clear.</AbstractText>A total of 94 patients (age 68.1 &#xb1; 11.1 years, 26 men) with implanted RVA-based dual-chamber pacemakers were recruited into this study. Patients who were pacemaker-dependent, in persistent atrial fibrillation or left ventricular ejection fraction &lt;45% were excluded. Echocardiography (iE33, Philips, Andover, MA, USA) was performed during intrinsic ventricular conduction (V-sense) and RVA pacing (V-pace) with 15 minutes between switching modes. The total maximal LA volume (LAV(max)), preatrial contraction volume (LAV(pre)), and minimal volume (LAV(min)) were assessed by area-length method. Peak systolic, early diastolic, and peak late diastolic (atrial contractile) velocity (Sm-la, Em-la, and Am-la) and strain (&#x25b;s-la, &#x25b;e-la, and &#x25b;a-la) were measured by color-coded tissue Doppler imaging (TDI) in four mid-LA walls at apical four- and two-chamber views.</AbstractText>During V-pace, LA volumes increased significantly compared with V-sense (LAV(max): 52.0 &#xb1; 18.8 vs 55.2 &#xb1; 21.1 mL, P = 0.005; LAV(pre): 39.8 &#xb1; 16.4 vs 41.3 &#xb1; 16.6 mL, P = 0.014; LAV(min): 27.4 &#xb1; 14.0 vs 29.1 &#xb1; 15.1 mL, P = 0.001). TDI parameters showed significant reduction in Sm-la and Em-la. Furthermore, &#x25b;s-la, &#x25b;e-la, and &#x25b;a-la decreased significantly, especially in patients with preexisting diastolic dysfunction (all P &lt; 0.01).</AbstractText>RVA pacing acutely induced LA enlargement and impaired atrial contractility. Patients with preexisting diastolic dysfunction may be more vulnerable to develop LA dysfunction and remodeling after acute RVA pacing.</AbstractText>&#xa9;2012, The Authors. Journal compilation &#xa9;2012 Wiley Periodicals, Inc.</CopyrightInformation>
14,174
[Coronary ventricular fistula as a late complication of permanent pacing].
A coronary angiography performed for the occurrence of atypical chest pain allowed us to discover a coronary-right ventricular fistula as a rare complication of myocardial penetration by a tined ventricular catheter implanted some years earlier.
14,175
[Cardiac resynchronization therapy: mortality, rehospitalization, and procedure-related complications. A three-year single-center observational study within the Italian Health System].
The aim of this study was to evaluate whether the benefit of cardiac resynchronization therapy with an implantable defibrillator (CRT-D) may differ among classes of indications to device therapy.</AbstractText>All-cause mortality, first hospitalization for non-fatal heart failure, stable improvement of NYHA functional class (responders), and implant-related complications were evaluated retrospectively in 103 patients selected among those (n = 133) who received consecutively CRT-D between 2006 and 2009. Patients were divided into three groups: group IA (n = 65) included patients receiving CRT-D for a class IA indication; group IIa (n = 26) included patients with atrial fibrillation and QRS &#x2265; 130 ms receiving CRT-D for a class IA indication; nonconventional group (NC) (n = 12) included patients with an indication to defibrillator implantation extended to CRT-D because of NYHA class III-IV and echocardiographic evidence of electromechanical dyssynchrony. Echocardiographic examination was performed in all patients to identify wall target for left-side lead placement.</AbstractText>Group IIa patients were slightly older than group IA patients (p&lt;0.05); gender distribution, left ventricular ejection fraction at implantation, ischemic etiology, and heart failure treatment were comparable among groups (all p&gt;0.5), except for a higher digitalis use in group IIa patients (p&lt;0.05). In a mean observation period of 3 years (up to December 2010), the rates of fatal events (IA: 22%, IIa: 23%, NC: 20%), rehospitalization for worsening heart failure (IA: 30%, IIa: 33%, NC: 22%), clinical responders (IA: 78%, IIa: 78%, NC: 78%), implant-related complications requiring reintervention (IA: 15%, IIa: 19%, NC: 25%), including pocket or catheter infections (IA: 5%, IIa: 11%, NC: 8%) were comparable among groups (all p&gt;0.5).</AbstractText>In the "real world", the benefit of CRT-D in advanced heart failure patients might be comparable among class IA, IIa or NC indication.</AbstractText>
14,176
Protective role of simvastatin on isolated rabbit atrioventricular node during experimental atrial fibrillation model: role in rate control of ventricular beats.
The purpose of the present study was to determine (1) whether simvastatin (SV) modifies the rate-dependent conduction time and refractoriness of the atrioventricular (AV) node and (2) how it can change the protective mechanism of the AV node during atrial fibrillation (AF). Predefined stimulation protocols were applied to detect the electrophysiological parameters of the AV node, including atrial-His conduction time, effective refractory period (ERP), functional refractory period (FRP), concealed conduction, excitable index, and fatigue in two groups of isolated, perfused rabbit AV nodal preparations (N=16). The stimulation protocols (fatigue, recovery) were carried out during control and in the presence of SV (0.5, 0.8, 3, and 10 &#x3bc;M). Simulated AF was executed in a separate group (N=8), and specific indexes, including H-H mean, zone of concealment (ZOC), and concealed beats were recorded. SV, in a concentration-dependent manner, prolonged ERP, FRP, and Wenckebach cycle lengths. It (10 &#x3bc;M) significantly increased fatigue and the excitable index. In addition, SV elicited prolongation of ZOC and H-H mean at 3 and 10 &#x3bc;M. SV-evoked prolongation of nodal refractoriness and concealed conduction caused rate-dependent ventricular slowing effects during AF. The ability of simvastatin to decrease the excitable gap by its heterogeneous effects on nodal dual pathways proposes its protective role in AF.
14,177
Comparison of standard versus orthogonal ECG leads for T-wave alternans identification.
T-wave alternans (TWA), an electrophysiologic phenomenon associated with ventricular arrhythmias, is usually detected from selected ECG leads. TWA amplitude measured in the 12-standard and the 3-orthogonal (vectorcardiographic) leads were compared here to identify which lead system yields a more adequate detection of TWA as a noninvasive marker for cardiac vulnerability to ventricular arrhythmias. Our adaptive match filter (AMF) was applied to exercise ECG tracings from 58 patients with an implanted cardiac defibrillator, 29 of which had ventricular tachycardia or fibrillation during follow-up (cases), while the remaining 29 were used as controls. Two kinds of TWA indexes were considered, the single-lead indexes, defined as the mean TWA amplitude over each lead (MTWAA), and lead-system indexes, defined as the mean and the maximum MTWAA values over the standard leads and over the orthogonal leads. Significantly (P &lt; 0.05) higher TWA in the cases versus controls was identified only occasionally by the single-lead indexes (odds ratio: 1.0-9.9, sensitivity: 24-76%, specificity: 76-86%), and consistently by the lead-system indexes (odds ratio: 4.5-8.3, sensitivity: 57-72%, specificity: 76%). The latter indexes also showed a significant correlation (0.65-0.83) between standard and orthogonal leads. Hence, when using the AMF, TWA should be detected in all leads of a system to compute the lead-system indexes, which provide a more reliable TWA identification than single-lead indexes, and a better discrimination of patients at increased risk of cardiac instability. The standard and the orthogonal leads can be considered equivalent for TWA identification, so that TWA analysis can be limited to one-lead system.
14,178
Spontaneous termination of ventricular fibrillation in a patient with congenital coronary anomaly.
Sudden death is common in patients with congenital coronary artery anomalies mainly when the left main coronary artery originates from the right coronary sinus. Ventricular fibrillation in these patients is irreversible unless defibrillation can be rapidly performed. We describe a 57-year-old male with an anomalous origin of circumflex and the left anterior descending coronary arteries from the right coronary sinus. He developed two episodes of ventricular fibrillation that terminated spontaneously, 10 hours after percutaneous revascularization of the circumflex coronary artery. Computed tomography angiography, in addition to confirming the anomalous origin of the coronary arteries, showed a muscle bridge over the midportion of the left anterior descending coronary artery. This is the first report of spontaneous termination of ventricular fibrillation in a patient with congenital anomaly of the coronary arteries.
14,179
Early repolarization is an independent predictor of occurrences of ventricular fibrillation in the very early phase of acute myocardial infarction.
Recent evidence has linked early repolarization (ER) to idiopathic ventricular fibrillation (VF) in patients without structural heart disease. However, no studies have clarified whether or not there is an association between ER and the VF occurrences after the onset of an acute myocardial infarction (AMI).</AbstractText>This study retrospectively included 220 consecutive patients with an AMI (57 female; mean age, 69&#xb1;11 years) in whom the 12-lead ECGs before the AMI onset could be evaluated. The patients were classified on the basis of a VF occurrence within 48 hours after the AMI onset. Early repolarization was defined as an elevation of the QRS-ST junction of &gt;0.1 mV from baseline in at least 2 inferior or lateral leads, manifested as QRS slurring or notching. Twenty-one (10%) patients had a VF occurrence within 48 hours of the AMI onset. A multivariate analysis revealed that ER (odds ratio [OR], 7.31; 95% confidence interval [CI], 2.21-24.14; P&lt;0.01), a time from the onset to admission of &lt;180 minutes (OR, 3.77; 95% CI, 1.13-12.59; P&lt;0.05), and a Killip class greater than I (OR, 13.60; 95% CI, 3.43-53.99; P&lt;0.001) were independent predictors of VF occurrences. As features of the ER pattern, a J-point elevation in the inferior leads, greater magnitude of the J-point elevation, notched morphology of the ER, and ER with a horizontal/descending ST segment, all were significantly associated with a VF occurrence.</AbstractText>The presence of ER increased the risk of VF occurrences within 48 hours after the AMI onset.</AbstractText>
14,180
Mild hypothermia attenuates mitochondrial oxidative stress by protecting respiratory enzymes and upregulating MnSOD in a pig model of cardiac arrest.
Mild hypothermia is the only effective treatment confirmed clinically to improve neurological outcomes for comatose patients with cardiac arrest. However, the underlying mechanism is not fully elucidated. In this study, our aim was to determine the effect of mild hypothermia on mitochondrial oxidative stress in the cerebral cortex. We intravascularly induced mild hypothermia (33&#xb0;C), maintained this temperature for 12 h, and actively rewarmed in the inbred Chinese Wuzhishan minipigs successfully resuscitated after 8 min of untreated ventricular fibrillation. Cerebral samples were collected at 24 and 72 h following return of spontaneous circulation (ROSC). We found that mitochondrial malondialdehyde and protein carbonyl levels were significantly increased in the cerebral cortex in normothermic pigs even at 24 h after ROSC, whereas mild hypothermia attenuated this increase. Moreover, mild hypothermia attenuated the decrease in Complex I and Complex III (i.e., major sites of reactive oxygen species production) activities of the mitochondrial respiratory chain and increased antioxidant enzyme manganese superoxide dismutase (MnSOD) activity. This increase in MnSOD activity was consistent with the upregulation of nuclear factor erythroid 2-related factor 2 (Nrf2) mRNA and protein expressions, and with the increase of Nrf2 nuclear translocation in normothermic pigs at 24 and 72 h following ROSC, whereas mild hypothermia enhanced these tendencies. Thus, our findings indicate that mild hypothermia attenuates mitochondrial oxidative stress in the cerebral cortex, which may be associated with reduced impairment of mitochondrial respiratory chain enzymes, and enhancement of MnSOD activity and expression via Nrf2 activation.
14,181
Effect of female sex on cardiac arrhythmias.
We performed a systematic literature review to examine the effect of female sex on cardiac electrophysiology and arrhythmias. Women have faster resting heart rates yet longer QTc intervals. Women also have shorter PR and QRS intervals; these are presumed to be due to the small heart size of women and hormonal effects on ion channels. Women are two times more likely to experience atrioventricular nodal re-entry tachycardia than men. In contrast to atrioventricular nodal re-entry tachycardia, accessory-pathway-mediated atrial arrhythmias are less common in women, and women have more concealed and fewer manifest accessory pathways. Supraventricular tachycardia in women varies with the menstrual cycle and is more frequent in the luteal phase and inversely correlated with estrogen levels. Atrial fibrillation (AF) is less prevalent in women, but the absolute number of women with AF is higher because AF prevalence increases with age and women live longer. Also, complications of AF are greater in women. Women are generally less prone to ventricular arrhythmias, but they comprise a higher percentage of symptomatic subjects with congenital long QT syndrome and are more often affected by drugs that prolong the QT. Women are less prone to arrhythmias during pregnancy although they commonly complain of palpitations, which are sometimes related to the increase in heart rate during pregnancy. Clinicians should explore the relationship of arrhythmias to the menstrual cycle in female patients and should know that the menstrual cycle may affect the induction of arrhythmias during electrophysiological testing. Clinicians should also be aware that the arrhythmia and the result of clinical trials examining arrhythmia treatment may have different implications in women than in men.
14,182
Current and emerging indications for implantable cardiac monitors.
Implantable cardiac monitors (ICMs) continuously monitor the patient's electrocardiogram and perform real-time analysis of the heart rhythm, for up to 36 months. The current clinical use of ICMs involves the evaluation of transitory symptoms of possible arrhythmic origin, such as unexplained syncope and palpitations. Moreover, ICMs can also be used for the evaluation of difficult cases of epilepsy and unexplained falls, though current indications for their application in these sectors are less clearly defined. Finally, the ability of new-generation ICMs to automatically record arrhythmic episodes suggests that these devices could also be used to study asymptomatic arrhythmias, and thus could be proposed for the long-term evaluation of the total (symptomatic and asymptomatic) arrhythmic burden in patients at risk of arrhythmic events. In particular, ICMs may have an emerging role in the management of patients with atrial fibrillation and in those at risk of ventricular arrhythmias.
14,183
Cortical infarction of the right parietal lobe and neurogenic heart disease: A report of three cases.
Three male patients were diagnosed with new cortical infarctions of the right parietal lobe on the basis of head magnetic resonance imaging; high-intensity signals indicating lesions in the right parietal lobe were noted on diffusion-weighted images at admission. Two of them presented with left hand weakness, and one exhibited left upper limb weakness. Treatment for improving blood supply to the brain was administered. One patient died suddenly because of ventricular fibrillation 3 days after admission. The other two patients had increased troponin levels and abnormal electrocardiograms, and were diagnosed with acute myocardial infarction half a month after admission. When lesions exist in field 7 of the parietal cortex (resulting in paralysis of the contralateral hand), the sympathetic center of the posterior lateral nucleus of the hypothalamus demonstrates compensatory excitement, which easily causes tachyarrhythmia and sudden death. Our experimental findings indicate that close electrocardiograph monitoring and cerebral infarction treatment should be standard procedures to predict and help prevent heart disease in patients with cerebral infarction in the right parietal lobe and left upper limb weakness as the main complaint.
14,184
Population-attributable risks for ischemic stroke in a community in South Brazil: a case-control study.
Risk factors for ischemic stroke are mostly known, but it is still unclear in most countries, what are their combined population-attributable risk percent (PAR%). In a case-control study the individual odds ratios (ORs) and the individual and combined PAR%, including risk factors not addressed in previous studies were estimated.</AbstractText>Cases and controls were selected from patients attending to an emergency department. Cases were patients aged with 45 years or more with the first episode of ischemic stroke, characterized by a focal neurological deficit or change in the mental status occurring during the previous 24 hours. Controls, matched to cases by age and gender, were selected from patients without neurological complaints.</AbstractText>133 cases and 272 controls were studied. Odds ratios for ischemic stroke were: atrial fibrillation (27.3; CI 95% 7.5-99.9), left ventricular hypertrophy (20.3; CI 95% 8.8-46.4), history of hypertension (11.2; CI 95% 5.4-23.3), physical inactivity (6.6; CI 95% 3.3-13.1), low levels of HDL-cholesterol (5.0; CI 95%2.8-8.9), heavy smoking (2.8; CI 95% 1.5-5.0), carotid bruit (2.5; CI 95% 1.3-4.6), diabetes (2.4; CI 95% 1.4-4.0) and alcohol abuse (2.1; CI 95% 1.1-4.0), The combination of these risk factors accounted for 98.9% (95% CI; 96.4%-99.7%) of the PAR% for all stroke.</AbstractText>Nine risk factors, easily identified, explain almost 100% of the population attributable risk for ischemic stroke.</AbstractText>
14,185
Omega-3 Fatty acids: anti-arrhythmic, pro-arrhythmic, or both?
This review focuses on developments after 2008, when the topic was last reviewed by the author. Pertinent publications were found by medline searches and in the author's personal data base. Prevention of atrial fibrillation (AF) was investigated in a number of trials, sparked by one positive report on the effects of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), considerations of upstream therapy, data from electrophysiologic laboratories and animal experiments. If EPA&#x2009;+&#x2009;DHA prevent postoperative AF, the effect is probably smaller than initially expected. The same is probably true for maintenance of sinus rhythm after cardioversion and for new-onset AF. Larger trials are currently ongoing. Prevention of ventricular arrhythmias was studied in carriers of an implanted cardioverter-defibrillator, with no clear results. This might have been due to a broad definition of the primary endpoint, including any ventricular arrhythmia and any action of the device. Epidemiologic studies support the contention that high levels of EPA&#x2009;+&#x2009;DHA prevent sudden cardiac death (SCD). However, since SCD is a rare occurrence, it is difficult to conduct an adequately powered trial. In patients with congestive heart failure, EPA&#x2009;+&#x2009;DHA reduced total mortality and rehospitalizations, but not SCD or presumed arrhythmic death. Of three trials in patients after a myocardial infarction, two were inadequately powered, and in one, the dose might have been too low. Taken together, while epidemiologic studies support an inverse relation between EPA&#x2009;+&#x2009;DHA and occurrence of SCD or arrhythmic death, demonstrating this effect in intervention trials remained elusive so far. A pro-arrhythmic effect of EPA&#x2009;+&#x2009;DHA has not been seen in intervention studies, and results of epidemiologic and animal studies also rather argue against such an effect. A different, and probably more productive, perspective is provided by a standardized analytical assessment of a person's status in EPA&#x2009;+&#x2009;DHA by use of the omega-3 index, EPA&#x2009;+&#x2009;DHA in red cell fatty acids. In populations with a high omega-3 index, SCD is rare. Intervention trials can become more effective by including a low omega-3 index into the inclusion criteria, thus creating a study population more likely to demonstrate an effect of EPA&#x2009;+&#x2009;DHA. This is especially relevant in case of rare endpoints, like new-onset AF or SCD.
14,186
Mexiletine differentially restores the trafficking defects caused by two brugada syndrome mutations.
The human cardiac sodium channel Na(v)1.5 encoded by the SCN5A gene plays a critical role in cardiac excitability and the propagation of action potentials. Na(v)1.5 dysfunctions due to mutations cause cardiac diseases such as the LQT3 form of long QT syndrome, conduction disorders, and Brugada syndrome (BrS). They have also recently been associated with dilated cardiomyopathy. BrS is characterized by coved ST-segment elevation on surface ECGs and lethal ventricular arrhythmias in an apparently structurally normal heart. Na(v)1.5 mutations that cause BrS result in a loss of channel function. Our aim was to functionally characterize two novel Na(v)1.5 mutations (A124D and V1378M) in BrS patients. Wild-type (WT) and mutant Na(v)1.5 channels were expressed in tsA201 cells in the presence of the &#x3b2;(1)-auxiliary subunit. The patch-clamp technique and immunocytochemistry approaches were used to study the mutant channels and their cellular localization. The two mutant channels displayed a dramatic reduction in current density but had normal gating properties. The reduction in current density was caused by the retention of channel proteins in the endoplasmic reticulum (ER). Mutant channel retention could be partially reversed by incubating transfected cells at 25&#xb0;C and by treating them with mexiletine (for V1378M but not A124D), or with curcumin or thapsigargin, two drugs that target ER resident proteins. It is likely that the clinical phenotypes observed in these two BrS patients were related to a surface expression defect caused by ER retention.
14,187
Case report: an unusual heart rhythm associated with organophosphate poisoning.
Organophosphate pesticides have emerged as a common cause of poisoning, particularly in developing countries. The most common electrocardiographic abnormalities observed in organophosphate poisoning are sinus tachycardia, QT interval prolongation, and, very rarely, ventricular arrhythmias. We report a case of organophosphate poisoning associated with atrial fibrillation, right bundle branch block, QT interval prolongation, and intermittent narrow QRS complexes that were most likely due to automaticity from the region of the left posterior fascicle.
14,188
[Early repolarisation syndrome and sudden cardiac death A.D. 2012. Early repolarisation or delayed depolarisation syndrome?].
Early repolarisation syndrome (ERS) appears in 2-7% of general population, mainly seen in young men, athletes and blacks. Recent publications change the benign character of ERS. It was suggested that ERS can be associated with sudden cardiac death, idiopathic ventricular fibrillation. This article described history and evolution of ERS.
14,189
Selective inhibitors of cardiac ADPR cyclase as novel anti-arrhythmic compounds.
ADP-ribosyl cyclases (ADPRCs) catalyse the conversion of nicotinamide adenine dinucleotide to cyclic adenosine diphosphoribose (cADPR) which is a second messenger involved in Ca(2+) mobilisation from intracellular stores. Via its interaction with the ryanodine receptor Ca(2+) channel in the heart, cADPR may exert arrhythmogenic activity. To test this hypothesis, we have studied the effect of novel cardiac ADPRC inhibitors in vitro and in vivo in models of ventricular arrhythmias. Using a high-throughput screening approach on cardiac sarcoplasmic reticulum membranes isolated from pig and rat and nicotinamide hypoxanthine dinuleotide as a surrogate substrate, we have identified potent and selective inhibitors of an intracellular, membrane-bound cardiac ADPRC that are different from the two known mammalian ADPRCs, CD38 and CD157/Bst1. We show that two structurally distinct cardiac ADPRC inhibitors, SAN2589 and SAN4825, prevent the formation of spontaneous action potentials in guinea pig papillary muscle in vitro and that compound SAN4825 is active in vivo in delaying ventricular fibrillation and cardiac arrest in a guinea pig model of Ca(2+) overload-induced arrhythmia. Inhibition of cardiac ADPRC prevents Ca(2+) overload-induced spontaneous depolarizations and ventricular fibrillation and may thus provide a novel therapeutic principle for the treatment of cardiac arrhythmias.
14,190
[Prehospital cardiac arrest. Therapeutic hypothermia in adults].
Therapeutic hypothermia is one of the few advances in recent years that has improved survival and neurological outcome of survivors of cardiac arrest. Therapeutic hypothermia is part of current guidelines and, therefore, should be part of the routine procedure in postresuscitation care of patients still comatose after primarily successful resuscitation. Early induction of hypothermia may be achieved even in the prehospital setting with different cooling techniques which, however, are less suitable to maintain a constant temperature and additionally do not allow precisely controlled re-warming. To achieve the goal of a target temperature of 32-34&#xb0;C for 12-24&#xa0;h, controlled feedback systems are more reliable and also can be used for patients during percutaneous coronary intervention. The optimal time point to start cooling is not well defined, even if theoretical considerations and animal experiments are in favor of beginning early. Another question is whether therapeutic hypothermia is of benefit for patients with cardiac arrest due to asystole and pulseless electrical activity in contrast to patients with ventricular fibrillation where it is of proven value.
14,191
Atrial fibrillation: the rate versus rhythm management controversy.
The fundamental management strategy for atrial fibrillation (AF) is still debated. There is no doubt that those patients at risk of thromboembolic events should be offered anticoagulant therapy. However, it is uncertain whether rhythm control (restoration and maintenance of sinus rhythm) or rate control (adjustment to a physiological ventricular rate while allowing AF to continue) is the preferred primary treatment option for the reduction of symptoms and major cardiovascular (CV) outcomes associated with AF. Several well conducted trials comparing the two strategies led to the conclusion that there was little to choose between them. However, guidelines leaned towards recommending rate control as the initial strategy, and reserved rhythm control for those who remained symptomatic. Recently this status quo is being increasingly challenged by the clear demonstration that left atrial catheter ablation is effective at suppressing AF resistant to traditional antiarrhythmic drugs, such as those that failed to demonstrate any superiority when compared with rate control. Also, recently introduced antiarrhythmic therapy may have superior efficacy with regard to reducing unexpected CV hospitalization, CV mortality and stroke. In addition, there is a growing perception that atrial remodelling should be best prevented by early rhythm control rather than delaying until rate control has proven unsatisfactory. For these reasons the results of large randomised clinical trials, which recruit patients soon after the presentation of AF and compare 'aggressive' modern rhythm control against the guideline approach of primary rate control, are eagerly awaited. In the meantime the pendulum of clinical opinion has begun to swing towards a rhythm control strategy.
14,192
Combination of opium smoking and hypercholesterolemia augments susceptibility for lethal cardiac arrhythmia and atherogenesis in rabbit.
Opium consumption is increasing in some eastern societies, where it is grown. We investigated the effect of opium smoking on plasma atherogenic index and incidence of lethal cardiac arrhythmia, i.e. ventricular tachycardia (VT) and ventricular fibrillation (VF) in rabbits. Animals were divided into two-, normo- and hyper-cholesterolemic main groups fed with normal or high cholesterol diet prior and during short-term and long-term exposure to opium smoke. Then, isoproterenol (3mg/kg, i.p.) was injected to induce cardiac ischemia and animals were followed for 3h for counting of lethal arrhythmia incidence. Long-term opium smoking significantly increased the plasma atherogenic index. In ischemic hearts, opium smoking along with hypercholesterolemia significantly enhanced the incidence of fatal arrhythmia. This vulnerability was not mediated by changes in QT interval. These data suggest that opium smoking, especially in hypercholesterolemic conditions, can be a predisposing factor for atherogenesis and lethal arrhythmia.
14,193
Atrioventricular node functional remodeling induced by atrial fibrillation.
The atrioventricular node (AVN) plays a vital role in determining the ventricular rate during atrial fibrillation (AF). AF results in profound electrophysiological and structural remodeling in the atria as well as the sinus node. However, it is unknown whether AVN undergoes remodeling during AF.</AbstractText>To determine whether AVN undergoes functional remodeling during AF.</AbstractText>AVN conduction properties were studied in vitro in 9 rabbits with AF and 10 normal controls. A previously validated index of AVN dual-pathway electrophysiology, His-electrogram alternans, was used to monitor fast-pathway or slow-pathway (SP) AVN conduction in these experiments. AVN conduction properties were further studied in vivo in 7 dogs with chronic AF and 8 controls.</AbstractText>Compared with the control rabbits, the rabbits with AF had a longer AVN conduction time (83 &#xb1; 16 ms vs 68 &#xb1; 7 ms; P &lt;.01), longer AVN effective refractory period (141 &#xb1; 27 ms vs 100 &#xb1; 9 ms; P &lt;.01), an earlier transition from fast-pathway to SP conduction (at a longer prematurity, 249 &#xb1; 60 ms vs 171 &#xb1; 24 ms; P &lt;.01), and a slower ventricular rate during simulated AF (RR interval 249 &#xb1; 42 ms vs 202 &#xb1; 12 ms; P &lt;.01). Notably, a larger proportion of conducted beats utilized the SP in AF preparations (92% &#xb1; 12% vs 63% &#xb1; 32%; P &lt;.05). Long-term AF in dogs resulted in a longer atrioventricular conduction time and AVN effective refractory period and a slower ventricular rate during AF compared with the controls.</AbstractText>Pronounced AVN functional electrophysiological remodeling occurs after long-term AF, which could lead to a spontaneous slowing of the ventricular rate. Furthermore, the SP dominance during AF underscores the effectiveness of its modification by ablation for ventricular rate control during AF.</AbstractText>Copyright &#xa9; 2012 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.</CopyrightInformation>
14,194
Managing atrial fibrillation in the CRT patient: controversy or consensus?
The cumulative incidence of new onset atrial fibrillation (AF) in patients undergoing cardiac resynchronization therapy (CRT) is substantial, exceeding 25% in multiple recent studies. Although AF patients undergoing CRT show improved echocardiographic parameters, functional status, and quality of life in, they benefit to a lesser degree than do patients in normal sinus rhythm. They also exhibit a trend toward increased mortality. Understanding the barriers to response from CRT among AF patients is critical to addressing the needs of growing populations of patients with AF and HF. Foremost among these are suboptimal biventricular pacing, often characterized by fusion or pseudo-fusion complexes, leading to inefficient CRT delivery. Furthermore, AF increases the risk of inappropriate shocks, which lead to substantial psychiatric morbidity, increased risk of heart failure hospitalization, and may also increase mortality. Assiduous rate control is reasonable for all AF patients receiving CRT, but there is a paucity of data regarding specific antiarrhythmic drug therapy recommendations. For patients with permanent AF and severe symptoms, atrioventricular junction ablation appears effective in improving response by ensuring biventricular capture and reducing implantable cardioverter-defibrillator shock burden in selected patients. Catheter-based techniques such as pulmonary vein isolation appear more attractive and in the future may offer further advantages and lower risks, particularly for patients with paroxysmal AF.
14,195
Ischemic postconditioning at the initiation of cardiopulmonary resuscitation facilitates functional cardiac and cerebral recovery after prolonged untreated ventricular fibrillation.
Ischemic postconditioning (PC) with "stuttering" reintroduction of blood flow after prolonged ischemia has been shown to offer protection from ischemia reperfusion injury to the myocardium and brain. We hypothesized that four 20-s pauses during the first 3 min of standard CPR would improve post resuscitation cardiac and neurological function, in a porcine model of prolonged untreated cardiac arrest.</AbstractText>18 female farm pigs, intubated and isoflurane anesthetized had 15 min of untreated ventricular fibrillation followed by standard CPR (SCPR). Nine animals were randomized to receive PC with four, controlled, 20-s pauses, during the first 3 min of CPR (SCPR+PC). Resuscitated animals had echocardiographic evaluation of their ejection fraction after 1 and 4 h and a blinded neurological assessment with a cerebral performance category (CPC) score assigned at 24 and 48 h. All animals received 12 h of post resuscitation mild therapeutic hypothermia.</AbstractText>SCPR+PC animals had significant improvement in left ventricular ejection fraction at 1 and 4 h compared to SCPR (59&#xb1;11% vs. 35&#xb1;7% and 55&#xb1;8% vs. 31&#xb1;13% respectively, p&lt;0.01). Neurological function at 24h significantly improved with SCPR+PC compared to SCPR alone (CPC: 2.7&#xb1;0.4 vs. 3.8&#xb1;0.4 respectively, p=0.003). Neurological function significantly improved in the SCPR+PC group at 48 h and the mean CPC score of that group decreased from 2.7&#xb1;0.4 to 1.7&#xb1;0.4 (p&lt;0.00001).</AbstractText>Ischemic postconditioning with four 20-s pauses during the first 3 min of SCPR improved post resuscitation cardiac function and facilitated neurological recovery after 15 min of untreated cardiac arrest in pigs.</AbstractText>Copyright &#xa9; 2012 Elsevier Ireland Ltd. All rights reserved.</CopyrightInformation>
14,196
Transapical aortic valve implantation in Rouen: four years' experience with the Edwards transcatheter prosthesis.
The first French transapical transcatheter aortic valve implantation (TAVI) was performed in July 2007 in our department.</AbstractText>To report 4-year outcomes of transapical implantation with the Edwards transcatheter bioprosthesis.</AbstractText>We prospectively evaluated consecutive patients who underwent transapical implantation with an Edwards transcatheter bioprosthesis between July 2007 and October 2011. Patients were not suitable for conventional surgery (due to severe comorbidities) or transfemoral implantation (due to poor femoral access).</AbstractText>Among 61 patients (59.0% men), mean logistic EuroSCORE was 27.5 &#xb1; 14.9% and mean age was 81.0 &#xb1; 6.8 years. Successful valve implantation was achieved in 59/61 patients (96.7%) of patients. The other two patients required conversion to conventional surgery due to prosthesis embolization and died. Six additional patients died in the postoperative period. Causes of perioperative death were two septic shocks (one of peritonitis), two multi-organ failure, one ventricular fibrillation and one respiratory insufficiency. Intraprocedural stroke was not observed in any patient. The actuarial survival rates at 1, 2 and 4 years were 73.8%, 67.2% and 41.0%. During this 4-year period, four patients died of cardiovascular events, but no impairment of transprosthesis gradient was observed.</AbstractText>Our series of 61 patients who underwent transapical implantation of the Edwards transcatheter bioprosthesis shows satisfactory results, similar to other reports, considering the high level of severity of patients referred for this method. Transapical access is a reliable alternative method for patients that cannot benefit from a transfemoral approach.</AbstractText>Copyright &#xa9; 2012. Published by Elsevier Masson SAS.</CopyrightInformation>
14,197
Cryoablation during left ventricular assist device implantation reduces postoperative ventricular tachyarrhythmias.
The number of patients undergoing implantation of a HeartMate II left ventricular assist device (LVAD; Thoratec Corporation, Pleasanton, Calif) is rising. Ventricular tachyarrhythmia (VA) after placement of the device is common, especially among patients with preoperative VA. We sought to determine whether intraoperative cryoablation in select patients reduces the incidence of postoperative VA.</AbstractText>From January 2009 through September 2010, 50 consecutive patients undergoing implantation of the HeartMate II LVAD were examined. Fourteen of these patients had recurrent preoperative VA. Of those patients with recurrent VA, half underwent intraoperative cryoablation (Cryo: n&#xa0;=&#xa0;7) and half did not (NoCryo: n&#xa0;=&#xa0;7). Intraoperatively, patients underwent localized epicardial and endocardial cryoablation via LVAD ventriculotomy. Cryothermal lesions were created to connect scar to fixed anatomic borders in the region of clinical VA. Demographics, risk factors, intraoperative features, and outcomes were analyzed to investigate the feasibility of cryoablation.</AbstractText>Thirty-day mortality remained low (n&#xa0;=&#xa0;1, 2%) among all LVAD recipients. There were no differences in risk factors between groups except that preoperative inotropes were less prevalent in Cryo patients (P&#xa0;=&#xa0;.09). Compared with NoCryo, the Cryo group had significantly decreased postoperative resource use and complications (P&#xa0;&lt;&#xa0;.05). Recurrent postoperative VA did not develop in any of the Cryo patients (P&#xa0;=&#xa0;.02).</AbstractText>Postoperative VA can be minimized by preoperative risk assessment and intraoperative treatment. Localized cryoablation in select patients offers promising early feasibility when performed during HeartMate II LVAD implantation. Further prospective analysis is required to investigate this novel approach.</AbstractText>Copyright &#xa9; 2013 The American Association for Thoracic Surgery. Published by Mosby, Inc. All rights reserved.</CopyrightInformation>
14,198
Effect of lipid lowering on new-onset atrial fibrillation in patients with asymptomatic aortic stenosis: the Simvastatin and Ezetimibe in Aortic Stenosis (SEAS) study.
Lipid-lowering drugs, particularly statins, have anti-inflammatory and antioxidant properties that may prevent atrial fibrillation (AF). This effect has not been investigated on new-onset AF in asymptomatic patients with aortic stenosis (AS).</AbstractText>Asymptomatic patients with mild-to-moderate AS (n = 1,421) were randomized (1:1) to double-blind simvastatin 40 mg and ezetimibe 10 mg combination or placebo and followed up for a mean of 4.3 years. The primary end point was the time to new-onset AF adjudicated by 12-lead electrocardiogram at a core laboratory reading center. Secondary outcomes were the correlates of new-onset AF with nonfatal nonhemorrhagic stroke and a combined end point of AS-related events.</AbstractText>During the course of the study, new-onset AF was detected in 85 (6%) patients (14.2/1,000 person-years of follow-up). At baseline, patients who developed AF were, compared with those remaining in sinus rhythm, older and had a higher left ventricular mass index a smaller aortic valve area index. Treatment with simvastatin and ezetimibe was not associated with less new-onset AF (odds ratio 0.89 [95% CI 0.57-1.97], P = .717). In contrast, age (hazard ratio [HR] 1.07 [95% CI 1.05-1.10], P &lt; .001) and left ventricular mass index (HR 1.01 [95% CI 1.01-1.02], P &lt; .001) were independent predictors of new-onset AF. The occurrence of new-onset AF was independently associated with 2-fold higher risk of AS-related outcomes (HR 1.65 [95% CI 1.02-2.66], P = .04) and 4-fold higher risk of nonfatal nonhemorrhagic stroke (HR 4.04 [95% CI 1.18-13.82], P = .03).</AbstractText>Simvastatin and ezetimibe were not associated with less new-onset AF. Older age and greater left ventricular mass index were independent predictors of AF development. New-onset AF was associated with a worsening of prognosis.</AbstractText>Copyright &#xa9; 2012 Mosby, Inc. All rights reserved.</CopyrightInformation>
14,199
Long QT syndrome and dilated cardiomyopathy with SCN5A p.R1193Q polymorphism: cardioverter-defibrillator implantation at 27 months.
Cardiac sodium channel dysfunction associated with the SCN5A gene presents with mixed phenotypes, including long QT syndrome type 3, sinus node dysfunction, and dilated cardiomyopathy (DCM). We report a Korean case of an overlap syndrome of cardiac sodium channelopathy with SCN5A p.R1193Q polymorphism, treated by the placement of an intrapericardial implantable cardioverter-defibrillator (ICD) at the age of 27 months. Although the patient received two appropriate life-saving shocks for ventricular fibrillations, he eventually died of DCM progression. However, this case shows that intrapericardial ICD implantation is feasible in young children with a high risk for sudden cardiac death.