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11,800 | Blood stream infection in patients undergoing systematic off-pump coronary artery bypass: incidence, risk factors, outcome, and associated pathogens. | Blood stream infection (BSI) is a major cause of mortality and morbidity for patients undergoing cardiac surgery. However, information is lacking about patients undergoing off-pump coronary artery bypass (OPCAB). The purpose of this study was to assess the incidence, risk factors, outcome and associated pathogens of BSI after OPCAB.</AbstractText>One thousand ten consecutive patients undergoing OPCAB between 2001 and 2012 were included in a retrospective case-control study. A propensity-matched control was used for risk factor analysis.</AbstractText>Of the 1,010 patients, 26 patients (2.6%) had 32 episodes of BSI after surgery, which occurred at a median of 14 d after surgery. Gram-negative bacilli and gram-positive cocci were distributed equally. Methicillin-resistant Staphylococcus aureus was the pathogen identified most frequently, and the most common source of infection was a surgical site. The hospital mortality rate was 54%. By univariable analysis, diabetes mellitus, pre-operative renal impairment, pre-operative low hemoglobin, pre-operative endotracheal intubation, dialysis before or after surgery, cardiogenic shock, left ventricular ejection fraction of less than 40%, non-elective surgery, low number of distal anastomoses, atrial fibrillation after surgery, and re-operation for bleeding were significant risk factors. By multivariable analysis, the independent risk factors were left ventricular ejection fraction of less than 40%, low number of distal anastomoses, atrial fibrillation after surgery, and dialysis after surgery.</AbstractText>Blood stream infections remained a common complication after OPCAB, and the mortality was high. Gram-negative bacilli and gram-positive cocci were distributed equally. Methicillin-resistant S. aureus was the pathogen identified most frequently. Preventive tactics should target likely pathogens and high-risk patients undergoing OPCAB.</AbstractText> |
11,801 | Influence of mitral valve repair versus replacement on the development of late functional tricuspid regurgitation. | To study the determinants of functional tricuspid regurgitation (TR) progression after surgical correction of mitral regurgitation, including the influence of mitral valve (MV) repair (MVr) versus replacement (MVR) for degenerative mitral regurgitation.</AbstractText>From January 1995 to January 2006, 747 adults with MV prolapse underwent isolated MVr (n=683) or MVR (n=64; mechanical in 32). The mean age was 60.8 years, and 491 were men (66.0%). Moderate preoperative functional TR was present in 115 (15.4%). The MVR group had a greater likelihood of New York Heart Association class III or IV (75.0% vs 34.4%, P<.001), atrial fibrillation (20.3% vs 8.3%, P=.002), a lower left ventricular ejection fraction (61.0% vs 65.2%, P<.003), and a higher pulmonary artery pressure (50.1 vs 41.2 mm Hg, P=.001). The patients were monitored for a mean of 6.9 years (MVr) or 7.7 years (MVR; P=.075).</AbstractText>During late follow-up, no difference was found between the groups in the development of moderately severe or severe TR: 1 to 5 years (3.0% vs 3.3%, P=.91) and >5 years (6.1% vs 6.5%; P=.93). The univariate predictors of severe TR after 5 years were older age (hazard ratio [HR], 1.1; P=.011), female gender (HR, 6.86; P=.005), higher pulmonary artery pressure (HR, 1.05; P=.022), and larger left atrial size (HR, 2.11; P=.035). Two patients (0.26%) who had undergone initial MVr required reoperation for late functional TR. Another 2 patients had had the tricuspid valve addressed concurrent with reoperation for MVr failure. No tricuspid reoperations were required in the MVR group.</AbstractText>The risk of TR progression was low after MVr or MVR for MV prolapse. Timely MV surgery before the development of left atrial dilatation or pulmonary hypertension could further decrease the risk of TR progression during follow-up.</AbstractText>Copyright © 2014 The American Association for Thoracic Surgery. Published by Elsevier Inc. All rights reserved.</CopyrightInformation> |
11,802 | Relationship between heart rate and mortality and morbidity in the irbesartan patients with heart failure and preserved systolic function trial (I-Preserve). | Higher heart rate is associated with poorer outcomes in patients with heart failure and reduced ejection fraction (HF-REF). Less is known about the association between heart rate and outcomes in patients with heart failure and preserved ejection fraction (HF-PEF). Therefore, we examined the relationship between heart rate and outcomes in the irbesartan in patients with heart failure and preserved systolic function trial (I-Preserve) in patients with an ejection fraction >45% aged >60 years.</AbstractText>Heart rate was analysed as both a categorical (tertiles) and continuous variable. Patients in sinus rhythm (n = 3271) and atrial fibrillation (n = 696) were analysed separately. The outcomes examined were the primary endpoint of the trial (all-cause death or cardiovascular hospitalization), the composite of cardiovascular death or heart failure hospitalization (and its components) and all-cause death alone. Higher heart rate was associated with a significantly higher risk of all outcomes studied for patients in sinus rhythm, even after adjustment for other prognostic variables, including N-terminal pro-B-type natriuretic peptide. Each standard deviation (12.4 bpm) increase in heart rate was associated with an increase in risk of 13% for cardiovascular death or heart failure hospitalization (P = 0.002). No relationship between heart rate and outcomes was observed for patients in atrial fibrillation. Beta-blocker treatment did not reduce the heart rate-risk relationship.</AbstractText>In patients with heart failure and preserved ejection fraction, heart rate is in sinus rhythm an independent predictor of adverse clinical outcomes and might be a therapeutic target in this syndrome. Clinical Trial Registration - URL http://www.clinicaltrials.gov. Unique identifier: NCT 0095238.</AbstractText>© 2014 The Authors. European Journal of Heart Failure © 2014 European Society of Cardiology.</CopyrightInformation> |
11,803 | Early repolarization increases the occurrence of sustained ventricular tachyarrhythmias and sudden death in the chronic phase of an acute myocardial infarction. | We recently showed that the presence of early repolarization (ER) increases the risk of ventricular fibrillation occurrences in the early phase of acute myocardial infarction (AMI). This study aimed to clarify whether an association exists between ER and occurrences of ventricular tachyarrhythmias or sudden death in the chronic phase of AMI.</AbstractText>This study retrospectively enrolled 1131 patients (67±12 years; 862 men) with AMIs surviving 14 days post-AMI. The primary end point was the occurrence of sustained ventricular tachyarrhythmias or sudden death >14 days after the AMI onset. We evaluated the presence of ER from the predischarge ECG (mean 10±3 days post-AMI). ER was defined as an elevation of the terminal portion of the QRS complex of >0.1 mV in inferior or lateral leads. After a median follow-up of 26.2 months, 26 patients had an episode of ventricular tachyarrhythmias or sudden death. A multivariable Cox regression analysis revealed the presence of ER (hazard ratio, 5.37; 95% confidence interval, 2.27-12.69; P<0.001), Killip class on admission of >I (hazard ratio, 2.75; 95% confidence interval, 1.24-6.07; P=0.013), and a left ventricular ejection fraction of <35% (hazard ratio, 11.83; 95% confidence interval, 5.16-27.13; P<0.001) were significantly associated with event occurrences. As features of the ER pattern, ER in the inferior leads, high-amplitude ER, a notched morphology, and ER without ST-segment elevation were associated with an increased risk of event occurrences.</AbstractText>ER observed at a mean of 10 days post-AMI may be a marker for a subsequent risk of ventricular tachyarrhythmias or sudden death.</AbstractText>© 2014 American Heart Association, Inc.</CopyrightInformation> |
11,804 | The impact of nonsustained ventricular tachycardia on reverse remodeling, heart failure, and treated ventricular tachyarrhythmias in MADIT-CRT. | This study determined whether the presence of nonsustained ventricular tachycardia (NSVT) was predictive of clinical events in MADIT-CRT (multicenter automatic defibrillator implantation trial-cardiac resynchronization therapy) patients treated with CRT-defibrillator.</AbstractText>We analyzed 24-hour Holters for the presence of NSVT. Patients were then stratified by the etiology (ischemic or nonischemic) of cardiomyopathy. The impact of NSVT on heart failure events (HF), implantable cardioverter-defibrillator (ICD) therapy for rapid ventricular tachycardia (VT) or fibrillation (VF), and reverse remodeling was determined. At least a single episode of NSVT was recorded in 483 (49%) patients. These patients had a higher burden of premature ventricular contractions, lower percentage of biventricular (BiV) pacing, and significantly less reduction in left ventricular end-diastolic and end-systolic volumes. The risk of HF was significantly greater in patients with nonischemic cardiomyopathy and NSVT (hazard ratio [HR] 2.89; 95% confidence interval [CI]: 1.49-5.61; P = 0.002). The risk of rapid VT/VF was significantly greater (in both ischemic and nonischemic patients) when NSVT was observed (HR 2.06; 95% CI: 1.30-3.26; P = 0.002 in ischemic patients; HR 3.09; 95% CI: 1.80-5.28; P < 0.001 in nonischemic patients).</AbstractText>MADIT-CRT patients with NSVT had a high burden of ventricular ectopy, lower percentage of BiV pacing, and less reverse remodeling. These patients had an increase in HF (in nonischemic cardiomyopathy patients) and rapid VT/VF ICD therapies (in ischemic and nonischemic patients). These findings may have implications for the management of nonsustained ventricular ectopy in CRT patients.</AbstractText>© 2014 Wiley Periodicals, Inc.</CopyrightInformation> |
11,805 | Clinical experience of combined HeartWare ventricular assist device and implantable cardioverter defibrillator therapy. | The HeartWare continuous flow ventricular assist device (HVAD) is used in an increasing number of heart failure patients. In those patients, ventricular arrhythmias (VAs) are common and, consequently, many patients already have an implanted implantable cardioverter defibrillator (ICD) in place or receive ICD implantation after left ventricular assist device implantation. However, limited data on feasibility and necessity of combined ICD and HVAD therapy are available. In this study we present our technical and clinical experience.</AbstractText>Between 01/2010 and 06/2013, 41 patients received HVAD implantation. Twenty-six HVAD patients who already had an ICD device placed prior to HVAD implantation or received ICD implantation afterwards were enrolled in this study. Peri- and postoperative complications as well as ICD interrogations were documented and analyzed retrospectively. Mean patients age was 58.4 ± 12.6 years; 88.5% of patients were male. During mean follow-up of 12.2 ± 8.9 months, appropriate ICD interventions occurred in 9 patients (34.6%) due to ventricular tachyarrhythmia (n = 7) or ventricular fibrillation (n = 2). An inappropriate ICD intervention was seen in 1 patient (3.9%) due to tachycardic atrial fibrillation. Patients on HVAD with a history of VAs (n = 13) had a significantly higher incidence of ICD interventions compared to patients with primary prophylactic indication for ICD (n = 13; 53.8% vs. 7.7%; P = 0.015). No disturbance of ICD function was seen after HVAD implantation.</AbstractText>Combined ICD and HVAD therapy was safe and feasible, without electromagnetic interference between ICD and ventricular assist device. The incidence of ICD interventions was high in patients with a history of VAs, but low in patients with ICD implantation for primary prevention.</AbstractText>© 2014 Wiley Periodicals, Inc.</CopyrightInformation> |
11,806 | Ablation of epicardial ganglionated plexi increases atrial vulnerability to arrhythmias in dogs. | Previous studies have suggested that systematic ablation of ganglionated plexi (GP) could increase the short-term success rate of radiofrequency ablation for atrial fibrillation, but the long-term efficacy of this approach is not fully established.</AbstractText>Twenty-four mongrel dogs were divided into 3 groups: epicardial GP ablation group 1 (n=8), epicardial GP ablation group 2 (n=8), and a sham operation group (n=8). In the 2 epicardial GP ablation groups, the 4 major GP and the ligament of Marshall were systematically ablated. The effective refractory period and inducibility of tachyarrhythmias were measured before and immediately after GP ablation in epicardial GP ablation group 1 and 8 weeks later in the other 2 groups. Tyrosine hydroxylase and choline acetyltransferase expressions were also determined immunohistochemically 8 weeks later in the latter groups. Compared with epicardial GP ablation group 1 and the sham operation group, epicardial GP ablation group 2 had the shortest atrial and ventricular effective refractory period and the highest inducibility of atrial tachyarrhythmias. The inducibility of ventricular tachyarrhythmias among the 3 groups was comparable. The density of tyrosine hydroxylase- and choline acetyltransferase-positive nerves in the atrium was the highest in epicardial GP group 2, whereas there were no significant intergroup differences in the densities of these 2 types of nerves in the ventricle.</AbstractText>After 8 weeks of healing, epicardial GP ablation without additional atrial ablation was potentially proarrhythmic, which may be attributable to decreased atrial effective refractory period and hyper-reinnervation involving both sympathetic and parasympathetic nerves.</AbstractText>© 2014 American Heart Association, Inc.</CopyrightInformation> |
11,807 | Back pain, leg swelling and a cardiac arrest: an interesting case of endocarditis. | A 66-year-old woman with a history of tissue aortic valve replacement and chronic back pain presented to the emergency department with a suspected right leg deep vein thrombosis. A recent outpatient MRI had revealed discitis. A ventricular fibrillation cardiac arrest occurred in the emergency department. Cardiac output was restored on the fifth defibrillation. A transthoracic echocardiogram showed large aortic valve vegetations. Clinical impression was of infective endocarditis with cardiac arrest secondary to coronary artery embolisation. Peripheral blood cultures grew Cardiobacterium hominis, and appropriate intravenous antibiotic therapy was administered. The infected prosthetic valve was excised. The patient experienced postoperative complete heart block and a right hemisphere cerebrovascular accident, however she is now recovering well. This case describes an unusual case of infective endocarditis secondary to C. hominis, with disc, leg, coronary artery and brain septic embolisation. Infective endocarditis is an important differential diagnosis in multisystem presentations. |
11,808 | Ca2+/calmodulin-dependent protein kinase II increases the susceptibility to the arrhythmogenic action potential alternans in spontaneously hypertensive rats. | Action potential duration alternans (APD-ALT), defined as long-short-long repetitive pattern of APD, potentially leads to lethal ventricular arrhythmia. However, the mechanisms of APD-ALT in the arrhythmogenesis of cardiac hypertrophy remain undetermined. Ca(2+)/calmodulin-dependent protein kinase II (CaMKII) is known to modulate the function of cardiac sarcoplasmic reticulum and play an important role in Ca(2+) cycling. We thus aimed to determine the role of CaMKII in the increased susceptibility to APD-ALT and arrhythmogenesis in the hypertrophied heart. APD was measured by high-resolution optical mapping in left ventricular (LV) anterior wall from normotensive Wistar-Kyoto (WKY; n = 10) and spontaneously hypertensive rats (SHR; n = 10) during rapid ventricular pacing. APD-ALT was evoked at significantly lower pacing rate in SHR compared with WKY (382 ± 43 vs. 465 ± 45 beats/min, P < 0.01). These changes in APD-ALT in SHR were completely reversed by KN-93 (1 μmol/l; n = 5), an inhibitor of CaMKII, but not its inactive analog, KN-92 (1 μmol/l; n = 5). The magnitude of APD-ALT was also significantly greater in SHR than WKY and was completely normalized by KN-93. Ventricular fibrillation (VF) was induced by rapid pacing more frequently in SHR than in WKY (60 vs. 10%; P < 0.05), which was also abolished by KN-93 (0%, P < 0.05). Western blot analyses indicated that the CaMKII autophosphorylation at Thr287 was significantly increased in SHR compared with WKY. The increased susceptibility to APD-ALT and VF during rapid pacing in hypertrophied heart was prevented by KN-93. CaMKII could be an important mechanism of arrhythmogenesis in cardiac hypertrophy. |
11,809 | Early repolarization as a predictor of arrhythmic and nonarrhythmic cardiac events in middle-aged subjects. | Early repolarization (ER) in the inferior/lateral leads predicts mortality, but whether ER is a specific sign of increased risk for arrhythmic events is not known.</AbstractText>The purpose of this study was to study the association of ER and arrhythmic events and nonarrhythmic morbidity and mortality.</AbstractText>We assessed the prognostic significance of ER in a community-based general population of 10,846 middle-aged subjects (mean age 44 ± 8 years). The end-points were sustained ventricular tachycardia or resuscitated ventricular fibrillation (VT-VF), arrhythmic death, nonarrhythmic cardiac death, new-onset atrial fibrillation (AF), hospitalization for congestive heart failure, or coronary artery disease during mean follow-up of 30 ± 11 years. ER was defined as ≥0.1-mV elevation of J point in either inferior or lateral leads.</AbstractText>After including all risk factors of cardiac mortality and morbidity in Cox regression analysis, inferior ER (prevalence 3.5%) predicted VF-VT events (n = 108 [1.0%]) with a hazard ratio (HR) of 2.2 (95% confidence interval [CI] 1.1-4.5, P = .03) but not nonarrhythmic cardiac death (n = 1235 [12.2%]), AF (n = 1659 [15.2%]), congestive heart failure (n = 1752 [16.1%]), or coronary artery disease (n = 3592 [32.9%]) (P = NS for all). Inferior ER predicted arrhythmic death in cases without other QRS complex abnormalities (multivariate HR 1.68, 95 % CI 1.10-2.58, P = .02) but not in those with ER and other coexisting abnormalities in QRS morphology (HR 1.30, 95% CI 0.86-1.96, P = .22).</AbstractText>ER in the inferior leads, especially in cases without other QRS complex abnormalities, predicts the occurrence of VT-VF but not nonarrhythmic cardiac events, suggesting that ER is a specific sign of increased vulnerability to ventricular tachyarrhythmias.</AbstractText>Copyright © 2014 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.</CopyrightInformation> |
11,810 | Ranolazine ameliorates postresuscitation electrical instability and myocardial dysfunction and improves survival with good neurologic recovery in a rat model of cardiac arrest. | During ischemia, enhancement of the "late Na+ current" (I(NaL)) contributes to intracellular Ca2+ overload. Dysregulation of intracellular Ca2+ homeostasis plays a critical role in the pathophysiology of cardiac arrest and cardiopulmonary resuscitation (CPR), leading to ventricular arrhythmias and left ventricle (LV) dysfunction.</AbstractText>The purpose of this study was to investigate the effects of the I(NaL) blocker ranolazine on outcome of CPR in a rat model. We hypothesized that ranolazine might reduce postresuscitation arrhythmias and improve survival and recovery.</AbstractText>Eighteen rats were assigned to receive intravenous ranolazine 10 mg/kg or vehicle. Ventricular fibrillation was induced and untreated for 8 minutes. CPR then was performed for 8 minutes. ECG and arterial and right atrial pressures were monitored up to 3 hours after CPR. After resuscitation, LV function was monitored by echocardiography, and 72-hour survival with neurologic recovery was evaluated. Plasma was obtained for biomarkers of heart and brain injury.</AbstractText>All animals in the ranolazine group were resuscitated and survived up to 72 hours, whereas 72% in the vehicle group were resuscitated but 54% survived. The period of postresuscitation arrhythmia with hemodynamic instability was shorter in the ranolazine group compared to vehicle group (P < .02). Seventy-two hours after resuscitation, LV systolic and diastolic functions were better in the ranolazine group compared to vehicle (P < .05). Full neurologic recovery was observed in all ranolazine animals, whereas neurologic impairment persisted in the vehicle group (P < .02).</AbstractText>In this model, ranolazine pretreatment reduced postresuscitation electrical and hemodynamic instability and improved 72-hour postresuscitation LV function and survival with good neurologic recovery.</AbstractText>Copyright © 2014 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.</CopyrightInformation> |
11,811 | I-123 mIBG and Tc-99m myocardial SPECT imaging to predict inducibility of ventricular arrhythmia on electrophysiology testing: a retrospective analysis. | The purpose of this study is to assess mIBG uptake in scar border zone and its relation with ventricular arrhythmia (VA) inducibility on electrophysiology (EP) testing using I-123 mIBG SPECT and resting Tc-99m SPECT myocardial perfusion imaging (MPI).</AbstractText>Forty-seven patients from a previous clinical trial were retrospectively analyzed. These patients underwent I-123 mIBG and resting Tc-99m tetrofosmin SPECT, and EP testing. Twenty-eight patients were positive (EP+) and 19 patients were negative (EP-) for inducibility of sustained (>30 seconds) VA on EP testing. MPI scar extent, border zone extent, and mIBG uptake in border zone were used to predict VA inducibility on EP testing, respectively.</AbstractText>There was no significant difference in scar extent between the EP+ and EP- groups. The EP+ group had significantly larger border zone and lower mIBG uptake ratio in the border zone than the EP- group. Receiver operating characteristic (ROC) curve analysis showed that the prediction accuracy for border zone extent (area under ROC = 0.75) was better than scar extent (area under ROC = 0.66). The prediction accuracy was further improved (area under ROC = 0.78), when assessing mIBG uptake in the border zone.</AbstractText>A new tool has been developed to measure scar and border zone and to assess mIBG uptake in scar and border zone from combined I-123 MIBG SPECT and resting Tc-99m SPECT MPI. The mIBG uptake in the border zone predicted VA inducibility on EP testing with a promising accuracy.</AbstractText> |
11,812 | Erythropoietin administration facilitates return of spontaneous circulation and improves survival in a pig model of cardiac arrest. | In addition to its role in the endogenous control of erythropoiesis, recombinant human erythropoietin (rh-EPO) has been shown to exert tissue protective properties in various experimental models. However, its role in the cardiac arrest (CA) setting has not yet been adequately investigated.</AbstractText>The aim of this study is to examine the effect of rh-EPO in a pig model of ventricular fibrillation (VF)-induced CA.</AbstractText>Ventricular fibrillation was electrically induced in 20 piglets and maintained untreated for 8 minutes before attempting resuscitation. Animals were randomized to receive rh-EPO (5000 IU/kg, erythropoietin [EPO] group, n = 10) immediately before the initiation of chest compressions or to receive 0.9% Sodium chloride solution instead (control group, n = 10).</AbstractText>Compared with the control, the EPO group had higher rates of return of spontaneous circulation (ROSC) (100% vs 60%, P = .011) and higher 48-hour survival (100% vs 40%, P = .001). Diastolic aortic pressure and coronary perfusion pressure during cardiopulmonary resuscitation were significantly higher in the EPO group compared with the control group. Erythropoietin-treated animals required fewer number of shocks in comparison with animals that received normal saline (P = .04). Furthermore, the neurologic alertness score was higher in the EPO group compared with that of the control group at 24 (P = .004) and 48 hours (P = .021).</AbstractText>Administration of rh-EPO in a pig model of VF-induced CA just before reperfusion facilitates ROSC and improves survival rates as well as hemodynamic variables.</AbstractText>Copyright © 2014 Elsevier Inc. All rights reserved.</CopyrightInformation> |
11,813 | [Cardiac disease at risk in the young athlete]. | Physical training significantly reduces all cause mortality in the general population. Eligibility for competitive sport participation in athletes with cardiovascular diseases is based on recommendations. Incidence of sudden cardiac death in young athletes is low (0.5 to 2/100,000 athletes/year). The most common cardiac diseases at risk are hypertrophic cardiomyopathies, congenital coronary arteries abnormalities, arrhythmogenic right ventricular cardiomyopathy and acute myocarditis. Pre-participation screening is based on the cardiovascular evaluation, including ECG (repeated every 3years since the age of 12 and every 5years since the age of 20 to the age of 35). Some events are unpredictable (idiopathic ventricular fibrillation, sudden death related to congenital coronary arteries abnormalities or commotio cordis). A better access to public defibrillation is needed. |
11,814 | ST-segment elevation after direct current shock mimicking acute myocardial infarction: a case report and review of the literature. | External direct current (DC) shocks are and have long been commonly used for electrical cardioversion/defibrillation of atrial or ventricular arrhythmias. ST-segment elevation after cardio version with DC is an easily ignored phenomenon, occurring acutely and resolving during the first few minutes postshock. Here, we describe electrocardiographic findings of widespread ST-segment elevation lasting at least 1 hour after DC cardioversion for ventricular defibrillation due to Brugada syndrome and mimicking acute myocardial infarction (AMI). This case of ST-segment elevation without a dynamic and evolving AMI underscores the need to consider other causes of ST-segment elevation. |
11,815 | A case of thyroid storm with cardiac arrest. | A 23-year-old man became unconscious while jogging. He immediately received basic life support from a bystander and was transported to our hospital. On arrival, his spontaneous circulation had returned from a state of ventricular fibrillation and pulseless electrical activity. Following admission, hyperthyroidism led to a suspicion of thyroid storm, which was then diagnosed as a possible cause of the cardiac arrest. Although hyperthyroidism-induced cardiac arrest including ventricular fibrillation is rare, it should be considered when diagnosing the cause of treatable cardiac arrest. |
11,816 | Resuscitation with amiodarone increases survival after hemorrhage and ventricular fibrillation in pigs. | Supplemental digital content is available in the text.</AbstractText>The aim of this experimental study was to compare survival and hemodynamic effects of a low-dose amiodarone and vasopressin compared with vasopressin in hypovolemic cardiac arrest model in piglets.</AbstractText>Eighteen anesthetized male piglets (with a weight of 25.3 [1.8] kg) were bled approximately 30% of the total blood volume via the femoral artery to a mean arterial blood pressure of 35 mm Hg in a 15-minute period. Afterward, the piglets were subjected to 4 minutes of untreated ventricular fibrillation followed by 11 minutes of open-chest cardiopulmonary resuscitation. At 5 minutes, circulatory arrest amiodarone 1 mg/kg was intravenously administered in the amiodarone group (n = 9), while the control group received the same amount of saline (n = 9). At the same time, all piglets received vasopressin 0.4 U/kg intravenously administered and hypertonic-hyperoncotic solution 3-mL/kg infusion for 20 minutes. Internal defibrillation was attempted from 7 minutes of cardiac arrest to achieve restoration of spontaneous circulation. The experiment was terminated 3 hours after resuscitation.</AbstractText>Three-hour survival was greater in the amiodarone group (p = 0.02). After the successful resuscitation, the amiodarone group piglets had significantly lower heart rate as well as greater systolic, diastolic, and mean arterial pressure. Troponin I plasma concentrations were lower and urine output was greater in the amiodarone group.</AbstractText>Combined resuscitation with amiodarone and vasopressin after hemorrhagic circulatory arrest resulted in greater 3-hour survival, better preserved hemodynamic parameters, and smaller myocardial injury compared with resuscitation with vasopressin only.</AbstractText> |
11,817 | Pathogenesis of arrhythmias in a model of CKD. | Patients with CKD have an increased risk of cardiovascular mortality from arrhythmias and sudden cardiac death. We used a rat model of CKD (Cy/+) to study potential mechanisms of increased ventricular arrhythmias. Rats with CKD showed normal ejection fraction but hypertrophic myocardium. Premature ventricular complexes occurred more frequently in CKD rats than normal rats (42% versus 11%, P=0.18). By optical mapping techniques, action potential duration (APD) at 80% of repolarization was longer in CKD rats (78±4ms) than normal rats (63±3 ms, P<0.05) at a 200-ms pacing cycle length. Calcium transient (CaT) duration was comparable. Pacing cycle length thresholds to induce CaT alternans or APD alternans were longer in CKD rats than normal rats (100±7 versus 80±3 ms and 93±6 versus 76±4 ms for CaT and APD alternans, respectively, P<0.05), suggesting increased vulnerability to ventricular arrhythmia. Ventricular fibrillation was induced in 9 of 12 CKD rats and 2 of 9 normal rats (P<0.05); early afterdepolarization occurred in two CKD rats but not normal rats. The mRNA levels of TGF-β, microRNA-21, and sodium calcium-exchanger type 1 were upregulated, whereas the levels of microRNA-29, L-type calcium channel, sarco/endoplasmic reticulum calcium-ATPase type 2a, Kv1.4, and Kv4.3 were downregulated in CKD rats. Cardiac fibrosis was mild and not different between groups. We conclude that cardiac ion channel and calcium handling are abnormal in CKD rats, leading to increased vulnerability to early afterdepolarization, triggered activity, and ventricular arrhythmias. |
11,818 | Catheter ablation of electrical storm in a patient with left ventricular assist device. | Catheter ablation is an effective treatment for ventricular tachycardia (VT) in structural heart disease to reduce VT recurrence and implantable cardioverter defibrillator shocks.Current guidelines recommend ablation in patients with recurrent or incessant VT. In patients with left ventricular assist device (LVAD), VTs may be well tolerated hemodynamically and catheter ablation has been performed rarely, until now. We present a case of successful VT ablation in a patient with LVAD and electrical storm. Effective ablation after a transseptal LV access was achieved using electroanatomic mapping and a substrate-based approach. On the basis of this case, we discuss the pros and cons of VT ablation in these patients. |
11,819 | Left atrial appendage dysfunction in acute cerebral embolism patients with sinus rhythm: correlation with pulse wave tissue Doppler imaging. | To evaluate left atrial appendage (LAA) dysfunction using left atrial pulse-wave tissue Doppler imaging (PW-TDI) in acute cerebral embolism (ACE) patients with sinus rhythm (SR), transthoracic (TTE) and transesophageal echocardiograhy (TEE) were performed in 60 consecutive patients with SR without obvious left ventricular dysfunction within 2 weeks after ACE. Two groups were identified: LAA dysfunction [LAA emptying peak flow velocity (LAA-eV) <0.55 m/s, n = 20, age 65 ± 10 years] and without LAA dysfunction (LAA-eV ≥ 0.55 m/s, n = 40, age 64 ± 10 years) on TEE. Left atrial wall motion velocity (WMV) was obtained from PW-TDI, with the sample volume placed at the left atrial anterior wall adjacent to ascending aortic inferior wall from the long axis view on TTE. WMVs showed triphasic waves: after the P wave (La') during systole (Ls'), and during early diastole. La' and Ls' were significantly lower in the group with versus without LAA dysfunction (4.9 ± 1.4 vs. 7.7 ± 1.8 cm/s, p < 0.0001; 5.3 ± 2.0 vs. 6.7 ± 1.9 cm/s, p < 0.001, respectively) and prevalence of paroxysmal atrial fibrillation, left atrial volume index, and serum levels of brain natriuretic peptide were significantly higher (60 vs. 15 %, p < 0.001; 32 ± 13 vs. 24 ± 13 ml/m(2), p < 0.05; 174 ± 279 vs. 48 ± 68 pg/ml, p < 0.01, respectively). La' was an independent predictor of LAA dysfunction (OR 0.380, 95 % CI 0.156-0.925, p < 0.05), and was significantly correlated with LAA-eV (r = 0.594, p < 0.0001) and LAA fractional area change (r = 0.682, p < 0.0001). The optimal cut-off value for LAA-eV < 0.55 m/s was 5.5 cm/s (sensitivity 83 %, specificity 88 %). La' is a useful and convenient strong predictor of LAA dysfunction in ACE patients with SR. |
11,820 | [Value of cardiopulmonary exercise test in cardiac function evaluation of patients with chronic left heart failure caused by dilated cardiomyopathy]. | To assess the value of cardiopulmonary exercise test in the evaluation of cardiac function in patients with chronic left heart failure caused by dilated cardiomyopathy.</AbstractText>Fifty-three inpatients aged 18 year and over with chronic left heart failure caused by dilated cardiomyopathy at Fuwai Hospital from October 2010 to October 2011 were selected and divided into 2 groups according to the New York Heart Association (NYHA) heart function classification. One group had 20 cases for class II and another 33 cases for class III-IV. All of them received cardiopulmonary exercise tests. Synchronous measurement and record of gas exchange indices were taken during every breath, and so were heart rate, blood pressure, electrocardiogram and blood oxygen saturation. At the same time, other routine tests were also performed. After exercise test, anaerobic threshold and peak oxygen consumption indices were calculated and statistically analyzed. They also received subsequent follow-ups of 1 day, 1 week, 1 month, 6 months and 1 year, including activities, clinical manifestations and cardiac adverse events.</AbstractText>At baseline, the differences in gender, age, body mass index, concurrent diseases, left ventricular end-diastolic diameter, left ventricular ejection fraction and serum creatinine had no statistical significance (P > 0.05). Compared with cardiac function class II group, the class III-IV group had higher left atrial diameter, level of amino terminal pro-B-type natriuretic peptide (NT-proBNP), incidence of atrial fibrillation ((51.4 ± 7.5) vs (43.6 ± 7.7) mm, (2 607 ± 1 782) vs (1 312 ± 901) µg/L, 42.4% (14/33) vs 5.0% (1/20)) and lower glomerular filtration rate, peak oxygen consumption, levels of anaerobic threshold ((72 ± 20) vs (97 ± 23) ml/min, (13.7 ± 2.6) vs (20.5 ± 3.6) ml·min(-1)·kg(-1), (10.7 ± 1.5) vs (13.3 ± 2.1) ml·min(-1)·kg(-1)) (all P < 0.01). And NT-proBNP and cardiac function classification showed a positive correlation (OR = 1.002, P = 0.003) while peak oxygen consumption, anaerobic threshold and cardiac function classification were negatively correlated (OR = 0.736, 0.608; P = 0.011, 0.001).</AbstractText>Cardiopulmonary exercise test objectively reflects the cardiopulmonary reserve of heart failure patients with dilated cardiomyopathy. And the parameters of anaerobic threshold and peak oxygen consumption may reflect the patient's motor ability quantitatively and accurately.</AbstractText> |
11,821 | The relationship between J wave on the surface electrocardiography and ventricular fibrillation during acute myocardial infarction. | We investigated whether the presence of J wave on the surface electrocardiography (sECG) could be a potential risk factor for ventricular fibrillation (VF) during acute myocardial infarction (AMI). We performed a retrospective study of 317 patients diagnosed with AMI in a single center from 2009 to 2012. Among the enrolled 296 patients, 22 (13.5%) patients were selected as a VF group. The J wave on the sECG was defined as a J point elevation manifested through QRS notching or slurring at least 1 mm above the baseline in at least two leads. We found that the incidence of J wave on the sECG was significantly higher in the VF group. We also confirmed that several conventional risk factors of VF were significantly related to VF during AMI; time delays from the onset of chest pain, blood concentrations of creatine phosphokinase and incidence of ST-segment elevation. Multiple logistic regression analysis demonstrated that the presence of J wave and the presence of a ST-segment elevation were independent predictors of VF during AMI. This study demonstrated that the presence of J wave on the sECG is significantly related to VF during AMI. |
11,822 | [Long-term survival of a patient with multiple myeloma-associated severe cardiac AL amyloidosis after implantation of a cardioverter-defibrillator]. | Cardiac involvement is by far the most relevant factor impacting poor outcomes of patients with systemic light-chain (AL) amyloidosis. Median survival of patients with symptomatic cardiac AL amyloidosis is less than 6 months. Approximately two-thirds of these patients die suddenly due to ventricular arrhythmias and electromechanical dissociation. We report a 56-year-old female with very severe cardiac AL amyloidosis (NT-proBNP 13,355 ng/l, troponin T 0.16 μg/l, and systolic blood pressure 100 mmHg), who was successfully treated with diuretics and an implantable cardioverter-defibrillator (ICD) and has survived for more than 4 years, to date. During the 4-year period after receiving the ICD, she experienced several episodes of sustained ventricular tachycardia and ventricular fibrillation, all successfully terminated by anti-tachycardia pacing or electrical shock. The benefit of ICD for cardiac AL amyloidosis is unclear since there have been only a few reports of successful use of this therapy for patients with cardiac AL amyloidosis. Recently, new treatment options for AL amyloidosis, such as bortezomib and lenalidomide, have shown high response rates and improved outcomes. It is important to identify those cardiac amyloidosis patients who might be more likely to benefit from ICD implantation. |
11,823 | The effect of strict rate control on B-type natriuretic peptide values and echocardiographic parameters in chronic atrial fibrillation. | There have been conflicting results about the role of strict rate control on cardiovascular outcomes in patients with chronic atrial fibrillation (AF). To date, large clinical studies have not shown a net clinical benefit derived from the current trend to specify the target ventricular rate according to the patient's own clinical and laboratory characteristics. Although the existing literature shows no superiority of strict rate control in clinical end points, it is difficult to assess the pure rate effect without commonly coexisting medication side effects which can also influence clinical end points.</AbstractText>To determine the effects of strict rate control in patients with chronic AF, regarding objective parameters such as echocardiographic data and B-type natriuretic peptide (BNP) values.</AbstractText>38 patients with chronic AF for whom strict rate control had been planned were enrolled in the study. Patients' echocardiographic parameters, BNP values and 24 h Holter electrocardiography findings showing the average heart rate (HR), were studied at baseline and then monthly, until the end of the 3rd month. Patients' negative dromotropic therapy was adjusted to achieve a target resting HR of below 80 bpm. Laboratory and echocardiographic parameters at baseline and at the end of the study were compared in the whole study group. The whole study group was subclassified according to the average resting HRs achieved, (group 1 with strict rate control < 80 bpm; n = 25, and group 2 without strict rate control; n = 13).</AbstractText>In group 1, the average HR declined from 101 ± 16.3 bpm to 77 ± 5.2 bpm. In group 2, the average HR was 96.6 ± 6.8 bpm at baseline and there was no significant change at the end of the study (94.2 ± 5.9 bpm). In group 1, there were significant decreases in BNP, left ventricular volumes, left atrial and right atrial areas at the end of the study. In group 2, BNP values were significantly higher at the end of the study despite similar ventricular and atrial dimensions according to the baseline. Diastolic functions were assessed roughly by septal E/e', but no significant change was observed in either group.</AbstractText>Strict rate control in patients with chronic AF yielded a significant decrease in BNP values as well as a reduction in volumes of cardiac chambers.</AbstractText> |
11,824 | Ten-year experience of an invasive cardiology centre with out-of-hospital cardiac arrest patients admitted for urgent coronary angiography. | The aim of the study was to evaluate survival and neurological function of out-of-hospital cardiac arrest (OHCA) patients admitted for urgent coronary angiography (UCA) with a view to percutaneous coronary intervention (PCI).</AbstractText>Hospital records of OHCA patients admitted to an invasive cardiology centre (providing 24 h a day/7 days a week service) in 2000-2010 were reviewed retrospectively, and similar data collected in 2011 were reviewed prospectively. Reports from the pre-hospital phase from emergency medical services (EMS) in Krakow were also analysed. Long-term follow-up data were collected by retrieving records from other hospitals (for patients transferred after UCA/PCI) and by phone calls to patients or their relatives.</AbstractText>In 2000-2011, 405 OHCA patients were admitted for UCA/PCI. Most (78%) had ventricular fibrillation (VF) or ventricular tachycardia (VT) as the primary mechanism of cardiac arrest (asystole: 13%, pulseless electrical activity: 3%, unknown: 6%). The mean patient age was 61 (range 20-85) years, and 81% were males. On admission, about 70% of patients were unconscious and 11% were in cardiogenic shock. The mean resuscitation time (time to return of spontaneous circulation [ROSC]) was 26.7 (range 1-126) min. ST-T changes seen in an electrocardiogram recorded after ROSC included ST elevation and depression in 52% of cases, only ST depression in 21% of cases, only ST elevation in 17% of cases, unspecific changes (due to intraventricular conduction disturbances) in 7% of cases, negative T waves in 3% of cases, and no changes in 0.5% of cases. Coronary angiography revealed acute coronary occlusion in 48% of cases, critical coronary stenosis (> 90%) in 26% of cases, other significant coronary lesions (> 50% stenosis) in 15% of cases, and non-significant lesions in 11% of cases. An acute coronary syndrome (ACS) was diagnosed in 82% of patients (75% STEMI, 25% NSTEMI), and other cardiac cause (mostly ischaemic cardiomyopathy) was identified in 13% of patients. Among OHCA patients diagnosed with ACS, PCI was performed in 90% and additional 4% underwent coronary artery bypass grafting. Overall success rate of PCI, defined as TIMI 3 flow plus residual stenosis < 50% and resolution of ST elevation after PCI by > 30%, was 70%. Survival to hospital discharge in the entire group of OHCA patients was 63% and 30-day survival with good neurological outcomes (defined as Cerebral Performance Category 1 or 2) was 49%. Among patients who were initially unconscious, those figures were 52% and 33%, respectively. During long-term follow-up (up to 12 years), 49% of patients were alive and 42% had good neurological function (87% of those who survived). In multivariate analysis, independent predictors of survival with good neurological outcomes were preserved consciousness on admission, absence of shock, cardiac arrest witnessed by medical personnel, VF/VT as a primary mechanism of cardiac arrest, and preserved renal function. Successful PCI predicted survival until hospital discharge only when the neurological status of the patients was not taken into account.</AbstractText>The most important cause of OHCA is coronary artery disease, in particular ACS. UCA and PCI seem to be important elements of appropriate post-resuscitation care because such treatment could improve survival but it is still unclear whether PCI might influence neurological outcomes as well.</AbstractText> |
11,825 | Haemodynamic effects of etomidate, propofol and electrical shock in patients undergoing implantable cardioverter-defibrillator testing. | Anaesthetic drugs and internal electrical shock may alter the haemodynamic status of patients undergoing implantable cardioverter-defibrillator (ICD) testing. Comparative data on the mechanisms of etomidate and propofol-induced changes in haemodynamic parameters are inconsistent. Also the effects of ICD shock on haemodynamics have not been extensively studied.</AbstractText>To compare the haemodynamic effects of etomidate and propofol as well as electrical shock during ICD testing in a prospective, randomised trial.</AbstractText>The study group consisted of 63 consecutive patients (mean age 66 ± 10 years, 51 males) who underwent ICD testing. Haemodynamic parameters were measured using impedance cardiography (Task Force Monitor Systems, CNSystems, Austria) before and after injection of etomidate (n = 30) or propofol (n = 33) as well as immediately after internal defibrillation of ventricular fibrillation (VF). Parameters measured included heart rate, systolic (sBP), diastolic (dBP) and mean (mBP) blood pressure, stroke volume (SV), cardiac output (CO) and total peripheral resistance (TPR).</AbstractText>Propofol significantly decreased the values of all measured parameters (sBP: 123.4 ± 17.1 vs. 106.3 ± 18 mm Hg, p < 0.0001; dBP: 83.7 ± 12.2 vs. 74.1 ± 13.8 mm Hg, p < 0.0001; mBP: 93.9 ± 13.1 vs. 81.1 ± 16.1 mm Hg, p < 0.0001; SV: 61.1 ± 19.3 vs. 56.4 ± 15.7 mL, p < 0.003; CO: 4.51 ± 1.07 vs. 4.17 ± 0.73 L/min, p < 0.003; and TPR: 1,735.8 ± 532.6 vs. 1,573.9 ± 390.5 dyn×s/cm⁵), whereas the only significant change following etomidate infusion was a decrease in SV (60.6 ± 11 vs. 56.8 ± 10 mL, p < 0.022). The propofol-induced changes were similar in patients with reduced (< 40%) vs. preserved (≥ 40%) left ventricular ejection fraction (LVEF) and in patients in heart failure NYHA class 0-II vs. class III-IV. Induction of VF and internal electrical shock did not cause major haemodynamic changes apart from significant, albeit very modest, drops in dBP and mBP (77 ± 2 vs. 72.9 ± 18 mm Hg, p < 0.002, and 85.2 ± 17 vs. 81.8 ± 20 mm Hg, p < 0.017, respectively). There were no complications during ICD testing.</AbstractText>Propofol significantly decreased BP probably by both reducing CO and causing vasodilatation, whereas etomidate only slightly decreased dBP and mBP without affecting other parameters. Propofol-induced changes were independent of LVEF or NYHA class. Induction of VF and internal defibrillation did not cause clinically significant changes apart from very modest drops in dBP and mBP values.</AbstractText> |
11,826 | Unusual perforation of the left ventricle during radiofrequency catheter ablation for ventricular tachycardia. | Cardiac perforation during catheter-based radiofrequency ablation procedures is relatively uncommon but potentially fatal if tamponade ensues. This complication should be promptly recognised. We present a case of incomplete perforation of the left ventricle with transient ST-segment elevation in leads V1 to V3 during catheter ablation of ventricular tachycardia. Complete perforation was avoided because of rapid diagnosis by the detection of subtle changes in electrode potentials and by performing angiography via an externally irrigated ablation catheter lumen. |
11,827 | Fragmented QRS can predict severity of aortic stenosis. | Fragmented QRS (fQRS) is an indicator of nonhomogeneous ventricular activity caused by myocardial fibrosis. Aortic stenosis (AS) is known to be a cause of myocardial fibrosis. We aimed to investigate the relationship of fQRS with severity of AS, echocardiographic, and electrocardiographic findings, and development of atrial fibrillation and manifest heart failure in AS patients.</AbstractText>One hundred four patients with moderate and severe AS were recruited for the study. Patients with mitral or tricuspid stenosis, previous myocardial infarction, segmental wall motion abnormality or left ventricular ejection fraction (LVEF) below 50% and patients with complete-incomplete BBB and pacemaker rhythm were excluded.</AbstractText>Mean age of the patients was 69 ± 14.8 and 73.1% had fQRS. Patients with fQRS had lower LVEF, higher mean QRS duration, intrinsic deflection, Cornell voltage, Romhilt-Estes Score, systolic pulmonary artery pressure, mean and peak systolic transaortic gradients and left atrium diameter. Manifest heart failure was more frequent in patients with fQRS. In stepwise multivariate logistic regression analyze, manifest heart failure, peak systolic transaortic gradient, LVEF, intrinsic deflection, strain pattern and Cornell voltage were independently associated with fQRS. Strain pattern and fQRS were found as independent predictors of severe AS.</AbstractText>fQRS is independently associated with the severity of AS while traditional LVH criteria, except strain pattern, are not. fQRS may be better than traditional ECG criteria of LVH and echocardiographic LVH as an indicator of myocardial fibrosis in AS. Thus, fQRS may have a role in determining the severity and prognosis of AS.</AbstractText>© 2014 Wiley Periodicals, Inc.</CopyrightInformation> |
11,828 | New oral anticoagulants vs vitamin K antagonists: benefits for health-related quality of life in patients with atrial fibrillation. | New oral anticoagulants (NOAC) have demonstrated their efficacy as an alternative to vitamin K antagonists (VKA) in the prophylaxis of cardioembolic events in patients with atrial fibrillation (AF). However, evidence on the benefits of NOAC in health-related quality of life (HRQoL) is lacking.We evaluated changes in HRQoL related to oral anticoagulation therapy employing a specific questionnaire in a cohort of 416 patients with AF undergoing electrical cardioversion. In terms of HRQoL, we observed a progressive adaptation to treatment with VKA; satisfaction with NOAC remained constant. Older age, higher left ventricular ejection fraction and NOAC were associated with better HRQoL. |
11,829 | Catheter ablation in patients with electrical storm: benefit of a network of cooperating clinics. | Catheter ablation has been shown to be an effective treatment for rhythm stabilization in patients with multiple ventricular arrhythmia episodes called electrical storm (ES). These procedures may be complex and are usually only performed in highly specialized and experienced centers. Still the optimum timing for catheter ablation in ES remains unclear.Early access to perform acute ablation should be considered in patients who are not rhythm stabilized with antiarrhythmic medical treatment. Also patients with hemodynamic compromise (cardiogenic shock) are candidates for an early interventional strategy. In specialized centers it is consensus to perform catheter ablation in these patients as early as eligible especially when considering a high early and late mortality without interventional management. Establishing a structured protocol for treatment and admission to EP centers has helped to further reduce pre-ablation mortality and may optimize treatment of ES. Large scale networking to optimize and structure access to experienced electrophysiology centers is of importance to create a basis for optimizing treatment strategies. |
11,830 | Predictors of functional outcome after intraoperative cardiac arrest. | Few outcome data are available about intraoperative cardiac arrest (IOCA). The authors studied 90-day functional outcomes and their determinants in patients admitted to the intensive care unit after IOCA.</AbstractText>Patients admitted to 11 intensive care units in a period of 2000-2013 were studied retrospectively. The main outcome measure was a day-90 Cerebral Performance Category score of 1 or 2.</AbstractText>Of the 140 patients (61 women and 79 men; median age, 60 yr [interquartile range, 46 to 70]), 131 patients (93.6%) had general anesthesia, 80 patients (57.1%) had emergent surgery, and 73 patients (52.1%) had IOCA during surgery. First recorded rhythms were asystole in 73 patients (52.1%), pulseless electrical activity in 44 patients (31.4%), and ventricular fibrillation/ventricular tachycardia in 23 patients (16.4%). Median times from collapse to cardiopulmonary resuscitation and return of spontaneous circulation were 0 min (0 to 0) and 10 min (5 to 20), respectively. Postcardiac arrest shock was identified in 114 patients (81.4%). Main causes of IOCA were preoperative complications (n = 46, 32.9%), complications of anesthesia (n = 39, 27.9%), and complications of surgical procedures (n = 36, 25.7%). On day 90, 63 patients (45.3%) were alive with Cerebral Performance Category score 1/2. Independent predictors of day-90 Cerebral Performance Category score 1/2 were day-1 Logistic Organ Dysfunction score (odds ratio, 0.78 per point; 95% CI, 0.71 to 0.87; P = 0.0001), ventricular fibrillation/tachycardia as first recorded rhythm (odds ratio, 4.78; 95% CI, 1.38 to 16.53; P = 0.013), and no epinephrine therapy during postcardiac arrest syndrome (odds ratio, 3.14; 95% CI, 1.29 to 7.65; P = 0.012).</AbstractText>By day 90, 45% of IOCA survivors had good functional outcomes. The main outcome predictors were directly related to IOCA occurrence and postcardiac arrest syndrome; they suggest that the intensive care unit management of postcardiac arrest syndrome may be amenable to improvement.</AbstractText> |
11,831 | Efficacy of long detection interval implantable cardioverter-defibrillator settings in secondary prevention population: data from the Avoid Delivering Therapies for Nonsustained Arrhythmias in ICD Patients III (ADVANCE III) trial. | Three trials demonstrated recently that a long detection window reduces implantable cardioverter-defibrillator (ICD) therapy in primary prevention patients. Avoid Delivering Therapies for Nonsustained Arrhythmias in ICD Patients III (ADVANCE III) was the only trial that enrolled both primary and secondary prevention patients.</AbstractText>Of the 1902 patients enrolled in the ADVANCE III trial, 477 received a defibrillator for secondary prevention; 248 patients were randomly assigned to a long detection setting (30 of 40 intervals) and 229 to the nominal setting (18 of 24 intervals) for ventricular arrhythmias with cycle length ≤ 320 ms. Eight-five percent of patients were men, with a mean age of 65 ± 12 years, a previous history of ventricular fibrillation in 37% of the cases, and a mean ejection fraction of 38 ± 13%. The ICD device mix was 37% single chamber, 47% dual chamber, and 16% triple chamber. Over a median period of 12 months, the long detection period was associated with a 25% reduction in the number of overall therapies (115.6 versus 86.8 per 100 patient-years; incidence rate ratio, 0.75; 95% confidence interval, 0.61-0.93; P=0.008) and a 34% reduction in the number of shocks (rate per 100 patient-years, 51.2 versus 38.1; incidence rate ratio, 0.66; 95% confidence interval, 0.48-0.89; P=0.007). Appropriate therapies (89.7 versus 67.7; incidence rate ratio, 0.77; 95% confidence interval, 0.60-0.97; P=0.029) and appropriate shocks (37.1 versus 28.1; incidence rate ratio, 0.64; 95% confidence interval, 0.45-0.93; P=0.018) were also reduced.</AbstractText>ADVANCE III is the first randomized trial to assess a long detection window setting in ICDs in both primary and secondary prevention populations and demonstrates a reduction of overall therapies and shocks in the subgroup of secondary prevention patients. These data suggest that even the secondary prevention population may benefit from programming that combines a long detection period with antitachycardia pacing during charging.</AbstractText>http://www/clinicaltrials.gov. Unique identifier: NCT00617175.</AbstractText>© 2014 American Heart Association, Inc.</CopyrightInformation> |
11,832 | B-type natriuretic peptide is a major predictor of ventricular tachyarrhythmias. | The cost-effective use of implantable cardioverter-defibrillators (ICDs) for the prevention of sudden cardiac death requires identification of patients at risk for ventricular tachyarrhythmias, not just for total mortality.</AbstractText>To determine whether N-terminal pro-B-type natriuretic peptide (NT-proBNP) or B-type natriuretic peptide (BNP) are independent predictors of ventricular arrhythmias in patients receiving primary prevention ICDs.</AbstractText>One hundred sixty-one patients with NT-proBNP levels and 403 patients with BNP levels at the time of ICD implantation were retrospectively assessed for the occurrence of first appropriate ICD therapy and mortality.</AbstractText>In multivariable Cox proportional hazards regression analysis, NT-proBNP or BNP levels in the upper 50th percentile were the strongest predictor of ICD therapy after adjustment for sex, age, left ventricular ejection fraction, New York Heart Association class, history of coronary artery disease, blood urea nitrogen, creatinine clearance, and history of atrial fibrillation (hazard ratio [HR] 5.75, P < .001 for NT-proBNP; HR 3.40, P = .01 for BNP). Patients were divided into quartiles on the basis of NT-proBNP or BNP levels. The adjusted HR for ICD therapy in the highest and second highest quartiles of NT-proBNP levels (HR 12.9, P < .001, and HR 4.6, P = .03, respectively) were higher than the adjusted HR for total mortality in these 2 quartiles (HR 3.4, P = .021 and HR 2.3, P = .13, respectively). Similarly, the adjusted HR for ICD therapy in the highest and second highest quartiles of BNP levels (HR 4.74, P = .01 and HR 2.17, P = .04, respectively) were higher than the adjusted HR for total mortality in these 2 quartiles (HR 3.05, P = .01 and HR 1.07, P = .3, respectively).</AbstractText>In this study, elevated baseline NT-proBNP and BNP levels are independently associated with the risk for ventricular tachyarrhythmias, which significantly exceeds the risk for total mortality, in multivariable analysis.</AbstractText>Copyright © 2014 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.</CopyrightInformation> |
11,833 | Renal disease and left atrial remodeling predict atrial fibrillation in patients with cardiovascular risk factors. | In this prospective population-based study, we tested the possible interaction between chronic kidney disease (CKD) and left atrium volume index (LAVI) in predicting incident atrial fibrillation (AF).</AbstractText>We enrolled 3549 Caucasian subjects, 1829 men and 1720 women, aged 60.7 ± 10.6 years, without baseline AF and thyroid disorders. Echocardiographic left ventricular mass and LAVI were measured. Renal function was calculated by estimated glomerular filtration rate (e-GFR). To test the effect of some clinical confounders on incident AF, we constructed different models including clinical and laboratory parameters. AF diagnosis was made by standard electrocardiogram or 24-h ECG-Holter, hospital discharge diagnoses, and by the all-clinical documentation.</AbstractText>During the follow-up (53.3 ± 18.1 months), 546 subjects developed AF (4.5 events/100 patient-years). Progressors to AF were older, had a higher body mass index, blood pressure, LDL-cholesterol, glucose, cardiac mass, and LAVI, and had lower e-GFR. Hypertension, metabolic syndrome, diabetes, cardiac hypertrophy and CKD were more common among AF cases than controls. In the final Cox regression model, variables that remained significantly associated with AF were: cardiac hypertrophy (HR=1.495, 95% CI=1.215-1.841), renal disease (HR=1.528, 95% CI=1.261-1.851), age (HR=1.586, 95% CI=1.461-1.725) and LAVI (HR=2.920, 95% CI=2.426-3.515). The interaction analysis demonstrated a synergic effect between CKD and cardiac hypertrophy (HR=4.040, 95% CI=2.661-6.133), as well as between CKD and LAVI (HR=4.875, 95% CI=2.699-8.805). The coexistence of all three subclinical organ damages significantly increases the arrhythmic risk (HR=7.185, 95% CI=5.041-10.240).</AbstractText>Our data demonstrate that LAVI and CKD significantly interact in a synergic manner in increasing AF risk.</AbstractText>Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.</CopyrightInformation> |
11,834 | Beau's Lines After Cardiac Arrest. | A 34-year-old man with uncontrolled hypertension suffered a ventricular fibrillation cardiac arrest from an obstructive left anterior descending artery occlusion. He was defibrillated more than 10 times before achieving return of spontaneous circulation. He was comatose after his arrest and was treated with therapeutic hypothermia, and a bare metal stent was placed in his obstructed coronary artery with restoration of excellent postobstruction blood flow. His postarrest course was complicated by cardiogenic shock; prolonged ventilator-dependent respiratory failure requiring tracheostomy; tracheobronchitis, with cultures positive for methicillin-resistant Staphylococcus aureus (MRSA); and an extended period of agitation and delirium. Thirty-four days after his arrest, his mental status started to improve rapidly. His delirium resolved, he became oriented and lucid, and he was able to be discharged to a rehabilitation facility on hospital day 41, with an excellent prognosis and close follow-up in primary care, cardiology, tracheostomy, and coumadin clinics. He returned to the emergency department 65 days later with the complaint of intermittent chest pain of 4 days' duration. Upon physical examination he was found to have Beau's lines on his fingernails. He was admitted to the hospital for a rule-out myocardial infarction workup, which was uneventful. He was discharged to home in good condition 2 days later. |
11,835 | Malignant arrhythmia as the first manifestation of Wolff-Parkinson-White syndrome: a case with minimal preexcitation on electrocardiography. | Wolff-Parkinson-White (WPW) syndrome is defined as the presence of an accessory atrioventricular pathway which is manifested as delta waves and short PR interval on electrocardiography (ECG). However, some WPW cases do not have typical findings on ECG and may remain undiagnosed unless palpitations occur. Sudden cardiac death may be the first manifestation of WPW and develops mostly secondary to degeneration of atrial fibrillation into ventricular fibrillation. In this report, we present a case of undiagnosed WPW with minimal preexcitation on ECG and who suffered an episode of malignant arrhythmia as the first manifestation of the disease. |
11,836 | Left ventricular hypertrophy and antiarrhythmic drugs in atrial fibrillation: impact on mortality. | Despite sparse clinical data, current atrial fibrillation (AF) guidelines favor amiodarone as a drug of choice for patients with left ventricular hypertrophy (LVH).</AbstractText>This study tested the hypothesis that patients with persistent AF and LVH on nonamiodarone antiarrhythmics have higher mortality compared to patients on amiodarone.</AbstractText>In an observational cohort analysis of patients who underwent cardioversion for AF, patients with LVH, defined as left ventricular wall thickness ≥1.4 cm, by echocardiogram prior to their first cardioversion, were included; clinical data, including antiarrhythmic drugs and ejection fraction (LVEF), were collected. Mortality, determined via the Social Security Death Index, was analyzed using Kaplan-Meier and Cox proportional hazards models to determine whether antiarrhythmic drugs were associated with higher mortality.</AbstractText>In 3,926 patients, echocardiographic wall thickness was available in 1,399 (age 66.8 ± 11.8 years, 67% male, LVEF 46 ± 15%, septum 1.3 ± 0.4, posterior wall 1.2 ± 0.2 cm), and 537 (38%) had LVH ≥1.4 cm. Among 537 patients with LVH, mean age was 67.5 ± 11.7 years, 76.4% were males, and mean LVEF was 48.3 ± 13.3%. Amiodarone was associated with lower survival (log rank P = 0.001), including after adjusting for age, LVEF, and coronary artery disease (P = 0.023). In propensity-score matched cohorts with LVH treated with no drugs, nonamiodarone antiarrhythmic drugs (non-AADs), or amiodarone (N = 65 each group), there was early lower survival in patients on amiodarone (P = 0.05).</AbstractText>Patients with persistent AF and LVH on non-AADs do not have higher mortality compared to patients on amiodarone. Importantly, these findings do not support amiodarone as a superior choice in patients with LVH.</AbstractText>©2014 Wiley Periodicals, Inc.</CopyrightInformation> |
11,837 | [Dual AV nodal nonreentry tachycardia (DAVNNT): unrecognized differential diagnosis with far-reaching consequences]. | The dual atrioventricular nodal nonreentry tachycardia (DAVNNT) is a rare form of tachycardia which occurs due to a time delayed double antegrade conduction via the slow and fast atrioventricular nodal pathways. Its epidemiology is not known so far. The aim of this article is to present the clinical findings in a series of patients with DAVNNT.</AbstractText>We retrospectively analyzed our database of patients who successfully underwent radiofrequency catheter ablation between January 2012 and March 2013 due to diagnosed supraventricular tachycardia.</AbstractText>In 3 out of 231 patients DAVNNT could be successfully treated by slow pathway modulation/ablation. Patients presented with widely varying symptoms including syncope, palpitations which had been mistaken as atrial fibrillation, and inappropriate defibrillator shocks due to suspected ventricular tachycardia.</AbstractText>The DAVNNT seems to be more common than previously thought. This important differential diagnosis needs to be taken into consideration as slow pathway modulation can be curative while a misdiagnosis, such as atrial fibrillation or ventricular tachycardia might result in over-treatment in patients with this arrhythmia.</AbstractText> |
11,838 | Short QT in a cohort of 1.7 million persons: prevalence, correlates, and prognosis. | Short QT syndrome (QTc ≤ 300 ms) is a novel hereditary channelopathy linked to syncope, paroxysmal atrial fibrillation, and sudden cardiac death. However, its epidemiological features remain unsettled.</AbstractText>(1) To assess the prevalence of short QT in a large population-based sample; (2) to evaluate its demographic and clinical correlates and; (3) to determine its prognosis.</AbstractText>A database of 6.4 million electrocardiograms (ECGs) obtained between 1995 and 2008 among 1.7 million persons was used. An internal, population-based method for heart rate correction (QTcreg ) was used and all ECGs with QTcreg ≤300 ms were manually validated. Linked health plan databases were used for covariate and survival ascertainment.</AbstractText>Of 6,387,070 ECGs, 1086 had an ECG with machine-read QTcreg ≤300 ms. Only 4% (45/1086) were validated yielding a prevalence of 0.7 per 100,000 or 1 of 141,935 ECGs. At the person level, the overall prevalence of QTcreg ≤300 ms was 2.7 per 100,000 or 1 of 37,335. The factors independently and significantly associated with validated QTcreg ≤300 ms were age over 65 years, Black race, prior history of ventricular dysrhythmias, chronic obstructive pulmonary disease, ST-T abnormalities, ischemia, bigeminy pattern, and digitalis effect. After 8.3 years of median follow-up and relative to normal QTcreg , validated QTcreg ≤300 ms was associated after multivariate adjustment with a 2.6-fold (95% confidence interval [CI] = 1.9-3.7) increased risk of death.</AbstractText>QTcreg ≤300 ms was extraordinarily rare and was associated with significant ECG abnormalities and reduced survival.</AbstractText>© 2014 Wiley Periodicals, Inc.</CopyrightInformation> |
11,839 | Putting class IIb recommendations to the test: the influence of unwitnessed and Non-VT/VF arrests on resource consumption and outcomes in therapeutic hypothermia and targeted temperature management. | Therapeutic hypothermia (TH) and targeted temperature management improve neurologic recovery, and survival for patients resuscitated from witnessed out-of-hospital ventricular tachycardia (VT) and ventricular fibrillation (VF) cardiac arrest. The American Heart Association recently gave a class IIb recommendation for the use of TH for non-VT/VF and unwitnessed arrests. We explored changes in baseline characteristics, resource use, and outcomes after expanding indications for TH at our institution based on these guidelines. Fifty-six consecutive patients treated with TH for out-of-hospital cardiac arrest were retrospectively evaluated based on whether they received treatment before (protocol 1) or after (protocol 2) broadening inclusion criteria. In protocol 1, TH was indicated after a witnessed VT/VF arrest. In protocol 2, TH was indicated for unwitnessed arrests, pulseless electrical activity, or asystole. Both populations undergoing TH had similarly extensive medical comorbidities and consumed considerable hospital resources. Overall, 64% of the patients from both protocols died in the hospital, although nominally lower mortality was seen in patients treated under protocol 1 compared with protocol 2 (59% vs. 67%, P = 0.57). Lower mortality was observed after VT/VF than after pulseless electrical activity or asystole (47% vs. 93% vs. 56%, P = 0.017). No patient survived following an unwitnessed arrest, and age (odds ratio per 10 years = 2.59; 95% confidence interval, 1.34-4.81) was independently associated with increased mortality. In an evolving field where best practice is still poorly defined, these data, along with future prospective studies in larger populations, should help to enhance care delivery and optimize cost-effectiveness strategies. |
11,840 | NT-proBNP in the mitral valve surgery. | Prognosis and severity of mitral valve disease in patients are reflected in their natriuretic peptide levels. Patients in the upper margin of this range with severe mitral valve dysfunction also present with a range of myocardial dysfunction and symptomatic progression. We investigated whether serial pre- and immediate postoperative measurements of N-terminal probrain natriuretic peptide (NT-proBNP) can serve as surrogate markers of these surgical patients' severity status and predictors of their immediate postoperative progress.</AbstractText>Clinical characteristics, echocardiographic indices, and preoperative and postoperative day 1, 5, 7 values of NT-proBNP were retrospectively recorded in a cohort of 75 patients who underwent mitral valve surgery. They were analyzed as a whole and separately for those suffering from severe mitral regurgitation. Correlations, multiple linear regression, logistic regression, and nonparametric receiver operating characteristic curve analyses were implemented.</AbstractText>The patients' preoperative New York Heart Association class, presence of atrial fibrillation, and left ventricular function were strongly correlated with the preoperative NT-proBNP level. Specifically for those with severe mitral regurgitation, preoperative NT-proBNP was also correlated to their left ventricular end-diastolic diameter. NT-proBNP values increased respectively postoperatively in all patients and were related to the preoperative values, the patients' preoperative characteristics, and the operative times. Logistic regression analysis identified preoperative NT-proBNP as a predictor of postoperative optimal clinical outcome (P < 0.001).</AbstractText>NT-proBNP is a valuable biomarker of the clinical presentation and immediate postoperative outcome in patients undergoing mitral valve surgery. The preoperative measurement of NT-proBNP can be used to predict an optimal postoperative clinical outcome.</AbstractText> |
11,841 | Mitral valve prolapse and electrolyte abnormality: a dangerous combination for ventricular arrhythmias. | A 27-year-old woman with a history of bileaflet mitral valve prolapse and moderate mitral regurgitation presented to our emergency with untractable polymorphic wide complex tachycardia and unstable haemodynamics. After cardiopulmonary resuscitation, return of spontaneous circulation was achieved 30 min later. Her post-resuscitation ECG showed a prolonged QT interval which progressively normalised over the same day. Her laboratory investigations revealed hypocalcaemia while other electrolytes were within normal limits. A diagnosis of ventricular arrhythmia secondary to structural heart disease further precipitated by hypocalcaemia was made. Further hospital stay did not reveal a recurrence of prolonged QT interval or other arrhythmias except for an episode of non-sustained ventricular tachycardia. However, the patient suffered diffuse hypoxic brain encephalopathy secondary to prolonged cardiopulmonary resuscitation. |
11,842 | Late Presentation of Recurrent Monomorphic Ventricular Tachycardia following Minimally Invasive Mitral Valve Repair due to Epicardial Injury. | We report a 73-year-old male with late onset monomorphic ventricular tachycardia following mitral valve repair (MVR). Typically, injury to epicardial arteries following mitral valve repair/replacement presents immediately as ventricular tachycardia/fibrillation, difficulty weaning from cardiopulmonary bypass, worsening ECG changes, increasing cardiac biomarkers, or new wall motion abnormalities. Our case illustrates a "late complication" of a distorted circumflex artery following mitral valve repair and the importance of early diagnostic angiography and percutaneous intervention. |
11,843 | [Electrical storm in ICD patients: prevention and treatment]. | Medical progress and demographic changes cause a continuous increase in patients with implantable cardioverter-defibrillators (ICD). Up to one third of patients with ICDs for secondary prevention and half of the patients with previous electrical storm (ES) will suffer from (further) ESs. When multiple ICD shocks are reported by patients (ICD storm), appropriate, inappropriate and phantom shocks have to be distinguished. Reported shocks without clinical correlates (phantom) often affect patients suffering from posttraumatic stress syndrome after an ICD storm. Approximately one third of all ICD shocks are inappropriate, most often due to supraventricular tachycardia with fast atrioventricular (AV) nodal conduction or lead failure. Within 10 years after implantation lead failure can be detected in up to 20 % of cases and approximately one third of these failures are only seen after inappropriate ICD shocks. Furthermore, inappropriate shocks are due to oversensing of far field atrial electrograms, T-waves, diaphragmatic potentials and electrical noise.Appropriate ICD shocks can rarely also be stimulated by the proarrhythmogenicity of lead implantation or ICD programming. Modifications of the waiting period to therapy, time to detection, detection window, antitachycardia pacing (ATP) stimulation and supraventricular discrimination algorithms may minimize ICD shocks. Some stimulation algorithms may improve the hemodynamic stability during ES. In addition to ventricular ablation, blockade of the sympathetic autonomic nervous system and antiarrhythmic treatment are the main pillars of ES treatment. The best ES prevention, however, is optimized heart failure treatment, especially when a cardiac resynchronization with defibrillator (CRT-D) system is implanted. |
11,844 | The vernakalant story: how did it come to approval in Europe and what is the delay in the U.S.A? | The sudden onset of atrial fibrillation (AF) is often associated with rapid irregular palpitations, chest pain, shortness of breath and considerable anxiety. If a patient presents shortly after the onset of the arrhythmia the physician may adopt initially an expectant "wait and see" policy, perhaps with the help of mild sedation and drug therapy to reduce the ventricular rate. If the arrhythmia does not terminate spontaneously and has been present for less than 24-48 hours restoration of sinus rhythm by cardioversion should be considered. This manuscript reviews the option of electrical cardioversion versus pharmacologic and the data for, the role of, and the status of vernakalant with respect to the latter. |
11,845 | [Catheter ablation of electrical storm: ready for prime time?]. | Electrical storm is an increasingly recognized clinical entity. It is generally defined as the occurrence of ≥ 3 episodes of potentially life-threatening ventricular arrhythmias during a time span of 24 h. Apart from pharmacological treatment options, catheter ablation remains a relatively novel, promising addition to the armamentarium of the cardiologist. Here, we will review the study data on ablation of patients with electrical storm. |
11,846 | Effect of novel modified bipolar radiofrequency ablation for preoperative atrial fibrillation combined with off-pump coronary artery bypass grafting surgery. | We described a novel modified bipolar radiofrequency (RF) ablation for preoperative atrial fibrillation (AF) combined with off-pump coronary artery bypass grafting (OPCABG) for patients with AF and coronary artery disease (CAD). The aim of this study was to assess the effect of this novel procedure and to determine whether it can eliminate AF for CAD patients. From January 2007 to June 2013, 45 patients (26 male patients) with AF (9 paroxysmal, 17 persistent, and 19 long-standing persistent) and CAD underwent the novel modified bipolar RF ablation combined with OPCABG in our department. After median sternotomy, the modified bipolar RF ablation and OPCABG were performed on beating heart without cardiopulmonary bypass. Pulmonary vein isolation and left atrium ablation were achieved using a bipolar RF champ. Mitral annular lesion and ganglionic plexus were ablated with a bipolar RF pen. The left atrial appendage was excluded using a surgical stapler. 24 h holter monitoring and echocardiography were performed at discharge and 3, 6, 12 months postoperatively as well as every year thereafter. The modified bipolar RF ablation and OPCABG were performed successfully in all patients. Mean AF ablation time was 33.6 ± 4.2 min, and mean OPCABG time was 87.6 ± 13.3 min. Mean postoperative hospital stay was 12.6 ± 5.5 days. The maintenance of sinus rhythm was 95.6 % (43/45) at discharge. There was no early death and permanent pacemaker implantation in perioperation. At a mean follow-up of 29.8 ± 10.2 months, 38 of 45 (84.4 %) patients were in sinus rhythm. Follow-up TTE at 6 months postoperatively showed that left atrial diameter was significantly reduced and left ventricular ejection fraction was significantly increased. The novel modified bipolar RF ablation procedure was safe, feasible and effective. It may be useful in selecting the best ablation approaches for patients with AF and CAD. |
11,847 | Epidemiological characteristics of sudden cardiac arrest in schools. | The present study aimed to clarify the incidence and outcomes of sudden cardiac arrests in schools and the clinically relevant characteristics of individuals who experienced sudden cardiac arrests.</AbstractText>We obtained data on sudden cardiac arrests that occurred in schools between January 1, 2005 and December 31, 2009 from the database of the Utstein Osaka Project, a population-based observational study on out-of-hospital cardiac arrests in Osaka, Japan. The data were analyzed to show the epidemiological features of sudden cardiac arrests in schools in conjunction with prehospital documentation. In total, 44 cases were registered as sudden cardiac arrests in schools during the study period. Of these, 34 cases had nontraumatic cardiac arrests. Twenty-one cases (62%) had pre-existing cardiac diseases and/or collapsed during physical exercise. Twenty-three cases (68%) presented with ventricular fibrillation or pulseless ventricular tachycardia, with cases of survival 1 month after cardiac arrest and those having favourable neurological outcome (Cerebral Performance Category 1 or 2) being 12 (52%) and 10 (43%), respectively. The incidence of sudden cardiac arrests in students was 0.23 per 100,000 persons per year, ranging from 0.08 in junior high school to 0.64 in high school. The incidence of sudden cardiac arrests in school faculty and staff was 0.51 per 100,000 persons per year, a rate approximately 2 times of that observed in the students.</AbstractText>Although sudden cardiac arrests in schools is rare, they majorly occurred in individuals with cardiac diseases and/or during physical exercise and presented as ventricular fibrillation or pulseless ventricular tachycardia observed initially as cardiac arrhythmia.</AbstractText>Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.</CopyrightInformation> |
11,848 | Usefulness of left ventricular diastolic function to predict recurrence of atrial fibrillation in patients with preserved left ventricular systolic function. | It is unknown whether recurrence of atrial fibrillation (AF) is related to severity of left ventricular diastolic dysfunction (LVDD) before ablation in patients with preserved left ventricular ejection fraction (LVEF). We tested the hypothesis that the presence and/or severity of LVDD before catheter ablation are related to AF recurrence during the 12-month follow-up period in patients with normal LVEF. We also aimed to determine what echocardiographic and Doppler indexes of LVDD before ablation are associated with recurrence of AF after ablation. We identified 198 patients with normal LVEF who underwent catheter ablation for AF with evidence of normal sinus rhythm within 1 year before ablation. The recurrence rate during 12-month follow-up period was assessed. Of the 198 patients, 76 patients (38%) had symptomatic recurrence and 122 patients (62%) had no recurrence. None of the independent variables, including mitral valve Doppler E and A peak velocities, E/A ratio, tissue Doppler e' and a' peak velocities, left atrial volume index, isovolumic relaxation time, and deceleration time, predicted recurrence. Patients with average E/e' ratio >13, however, had increased recurrence (67% vs 35%, odds ratio 3.70, 95% confidence interval 1.21 to 11.3, p <0.05). In conclusion, there was no difference in the severity of LVDD using conventional echocardiographic indexes of LVDD in patients with or without recurrence of AF ablation. However, patients with average E/e' ratio >13 did have an increased recurrence rate of AF at 12 months after procedure. Therefore, E/e' ratio, indicative of increased left atrial pressure, may serve as a marker for AF recurrence after ablation. |
11,849 | Occurrence of cardiac arrhythmias in Standardbred racehorses. | Cardiac arrhythmias are a recognised but poorly characterised problem in the Standardbred racehorse. Frequency data could aid the development of cardiac arrhythmia screening programmes.</AbstractText>To characterise the occurrence of cardiac arrhythmias in Standardbreds prior to racing and in the late post race period using a handheld, noncontinuous recording device.</AbstractText>Prospective, observational study, convenience sampling.</AbstractText>Noncontinuous electrocardiographic recordings were obtained over a 12 week period from Standardbred horses competing at a single racetrack. Electrocardiograms were obtained before racing and between 6 and 29 min after the race using a handheld recording device. Prevalence of arrhythmias was calculated for all horses and overall frequency of arrhythmias was calculated for race starts and poor performers. Univariate logistic regression analysis was used to identify risk factors for cardiac arrhythmias.</AbstractText>A total of 8657 electrocardiogram recordings were obtained from 1816 horses. Six horses had atrial fibrillation after racing (prevalence = 0.11%, frequency = 0.14%), one horse had supraventricular tachycardia before racing (prevalence = 0.06%, frequency = 0.02%), and 2 horses had ventricular tachyarrhythmias after racing (prevalence = 0.06%, frequency = 0.05%). The frequency of atrial fibrillation among race starts with poor performance was 1.3-2.0%. Increasing age was a significant risk factor for the presence of atrial premature contractions before racing and atrial fibrillation and ventricular ectopy after racing.</AbstractText>Both physiological and pathological cardiac arrhythmias can be detected in apparently healthy Standardbred horses in the prerace and late post race period using noncontinuous recording methods. Future studies should examine cumulative training or racing hours as a risk factor for cardiac arrhythmia. The prevalence and frequency information may be useful for track veterinarians and regulatory personnel following trends in cardiac arrhythmias.</AbstractText>© 2014 EVJ Ltd.</CopyrightInformation> |
11,850 | Short QT syndrome manifesting with neonatal atrial fibrillation and bradycardia. | Atrial fibrillation (AF) is rare during childhood and usually associated with other cardiovascular pathology. In lone AF, the ventricular response rate is usually rapid. We sought to describe a subset of children who present with early-onset AF and a slow ventricular response rate who were found to have the short QT syndrome (SQTS).</AbstractText>Using a MEDLINE/PubMed search, children with AF, a structurally normal heart and bradycardia were identified. Demographics, clinical presentation, electrocardiographic (ECG) findings, electrophysiologic testing, genetic analysis and follow-up assessment were collected on each child for analysis.</AbstractText>Four children were identified in the literature and combined with 2 other children followed by the authors. All had a short QT interval and those who were tested were found to have a gain-of-function mutation in the KCNQ1 gene.</AbstractText>We describe a subclass of children with SQTS who present with AF and a slow ventricular response. Medical therapy has not been effective in maintaining sinus rhythm. The long-term outcome remains unknown for these children. This condition may present in utero as persistent bradycardia with postnatal ECG showing a very short QT interval.</AbstractText>© 2014 S. Karger AG, Basel.</CopyrightInformation> |
11,851 | ICD programming to reduce shocks and improve outcomes. | Despite the clinical benefit of implantable cardioverter defibrillator (ICD), there is a high frequency of inappropriate ICD therapy associated with impaired quality of life, unwanted health care resource utilization, and adverse clinical outcome. Alternative strategies of ICD programming are needed to reduce the risk of inappropriate and "unnecessary" ICD therapies and to improve patient outcome. In this review, we provide an overview of the rate of inappropriate and appropriate ICD therapies in clinical trials and large registries as well as a review of current trials evaluating novel ICD programming to reduce inappropriate ICD therapy to avoid unnecessary ICD therapy. Based on recent studies including a large randomized trial, we recommend a simple programming approach involving high-rate device therapy beginning at 200 bpm with a 2.5 sec delay for it reduces inappropriate therapy, unnecessary therapy, and all-cause mortality in patients receiving ICD or CRT-D devices for primary prevention indications. |
11,852 | Upper limit of vulnerability during defibrillator implantations predicts the occurrence of appropriate shock therapy for ventricular fibrillation. | The utility of the upper limit of vulnerability (ULV) test in patients undergoing defibrillator implantation has been reported, so the purpose of this study was to evaluate the difference in the clinical outcomes between patients with ULV ≤15 J or >15 J.</AbstractText>A total of 165 patients receiving an implantable cardioverter-defibrillator underwent a vulnerability test. At the time of the implantation, we delivered a 15-J shock on the T-peak and ±20 ms later to cover the most vulnerable part of the cardiac cycle. The clinical outcomes were prospectively analyzed. A 15-J shock induced ventricular fibrillation (VF) in 30 patients (ULV >15 J) and did not in 135 (ULV ≤15 J). The characteristics of the 2 groups were comparable. After a mean follow-up of 757 days, Kaplan-Meier curve analysis showed that the ULV ≤15 J group experienced less VF than the ULV >15 J group (log-rank P=0.003). The occurrence of ventricular tachycardia was similar between the 2 groups (P=0.140). Furthermore, the effectiveness of ATP was comparable. After adjusting for other known predictors of shock therapy, a ULV >15 J was independently associated with the occurrence of VF (hazard ratio: 6.25; 95% confidence interval: 1.913-20.40; P<0.01).</AbstractText>A high ULV value was associated with a high incidence of VF, which suggests that cardiac vulnerability to electrical shock may be linked to electrical instability.</AbstractText> |
11,853 | Small-conductance calcium-activated potassium (SK) channels contribute to action potential repolarization in human atria. | Small-conductance calcium-activated potassium (SK) channels are expressed in the heart of various species, including humans. The aim of the present study was to address whether SK channels play a functional role in human atria.</AbstractText>Quantitative real-time PCR analyses showed higher transcript levels of SK2 and SK3 than that of the SK1 subtype in human atrial tissue. SK2 and SK3 were reduced in chronic atrial fibrillation (AF) compared with sinus rhythm (SR) patients. Immunohistochemistry using confocal microscopy revealed widespread expression of SK2 in atrial myocytes. Two SK channel inhibitors (NS8593 and ICAGEN) were tested in heterologous expression systems revealing ICAGEN as being highly selective for SK channels, while NS8593 showed less selectivity for these channels. In isolated atrial myocytes from SR patients, both inhibitors decreased inwardly rectifying K(+) currents by ∼15% and prolonged action potential duration (APD), but no effect was observed in myocytes from AF patients. In trabeculae muscle strips from right atrial appendages of SR patients, both compounds increased APD and effective refractory period, and depolarized the resting membrane potential, while only NS8593 induced these effects in tissue from AF patients. SK channel inhibition did not alter any electrophysiological parameter in human interventricular septum tissue.</AbstractText>SK channels are present in human atria where they participate in repolarization. SK2 and SK3 were down-regulated and had reduced functional importance in chronic AF. As SK current was not found to contribute substantially to the ventricular AP, pharmacological inhibition of SK channels may be a putative atrial-selective target for future antiarrhythmic drug therapy.</AbstractText>Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2014. For permissions please email: journals.permissions@oup.com.</CopyrightInformation> |
11,854 | Slow adaptation of ventricular repolarization as a cause of arrhythmia? | This article is part of the Focus Theme of Methods of Information in Medicine on "Biosignal Interpretation: Advanced Methods for Studying Cardiovascular and Respiratory Systems".</AbstractText>Adaptation of the QT-interval to changes in heart rate reflects on the body-surface electrocardiogram the adaptation of action potential duration (APD) at the cellular level. The initial fast phase of APD adaptation has been shown to modulate the arrhythmia substrate. Whether the slow phase is potentially proarrhythmic remains unclear.</AbstractText>To analyze in-vivo human data and use computer simulations to examine effects of the slow APD adaptation phase on dispersion of repolarization and reentry in the human ventricle.</AbstractText>Electrograms were acquired from 10 left and 10 right ventricle (LV/RV) endocardial sites in 15 patients with normal ventricles during RV pacing. Activation-recovery intervals, as a surrogate for APD, were measured during a sustained increase in heart rate. Observed dynamics were studied using computer simulations of human tissue electrophysiology.</AbstractText>Spatial heterogeneity of rate adaptation was observed in all patients. Inhomogeneity in slow APD adaptation time constants (Δτ(s)) was greater in LV than RV (Δτ(s)(LV) = 31.8 ± 13.2, Δτ(s)(RV) = 19.0 ± 12.8 s , P< 0.01). Simulations showed that altering local slow time constants of adaptation was sufficient to convert partial wavefront block to block with successful reentry.</AbstractText>Using electrophysiological data acquired in-vivo in human and computer simulations, we identify heterogeneity in the slow phase of APD adaptation as an important component of arrhythmogenesis.</AbstractText> |
11,855 | Rapid expansion of mycotic aneurysm of left coronary sinus of Valsalva causing myocardial ischemia: report of a case. | We described a 71-year-old female of aneurysm of the left sinus of Valsalva from mycotic origin. She underwent aortic valve replacement 11 years ago. Repeated CT scans showed rapidly growing aneurysm below the left coronary ostium. On sixth day after the admission, she suddenly developed myocardial ischemia complicated with ventricular fibrillation. The patient was treated with emergent aortic root replacement and she recovered. We recommend emergent surgical repair of mycotic saccular aneurysm of the left sinus of Valsalva because a delay of surgery could be fatal. |
11,856 | Electrical wave propagation in an anisotropic model of the left ventricle based on analytical description of cardiac architecture. | We develop a numerical approach based on our recent analytical model of fiber structure in the left ventricle of the human heart. A special curvilinear coordinate system is proposed to analytically include realistic ventricular shape and myofiber directions. With this anatomical model, electrophysiological simulations can be performed on a rectangular coordinate grid. We apply our method to study the effect of fiber rotation and electrical anisotropy of cardiac tissue (i.e., the ratio of the conductivity coefficients along and across the myocardial fibers) on wave propagation using the ten Tusscher-Panfilov (2006) ionic model for human ventricular cells. We show that fiber rotation increases the speed of cardiac activation and attenuates the effects of anisotropy. Our results show that the fiber rotation in the heart is an important factor underlying cardiac excitation. We also study scroll wave dynamics in our model and show the drift of a scroll wave filament whose velocity depends non-monotonically on the fiber rotation angle; the period of scroll wave rotation decreases with an increase of the fiber rotation angle; an increase in anisotropy may cause the breakup of a scroll wave, similar to the mother rotor mechanism of ventricular fibrillation. |
11,857 | Short stature and ischemic stroke in nonvalvular atrial fibrillation: new insight into the old observation. | For decades, repeated epidemiologic observations have been made regarding the inverse relationship between stature and cardiovascular disease, including stroke. However, the concept has not been fully evaluated in patients with atrial fibrillation (AF). We investigated whether patient's height is associated with ischemic stroke in patients with nonvalvular AF and attempted to ascertain a potential mechanism.</AbstractText>All 558 AF patients were enrolled: 211 patients with ischemic stroke (144 men, 68 ± 10 years) and 347 no-stroke patients (275 men, 56 ± 11 years) as a control group. Clinical characteristics and echocardiographic parameters were compared between the two groups.</AbstractText>(1) Stroke patients were shorter than those in the control group (164 ± 8, vs. 169 ± 8 cm, p<0.001). However, body mass index failed to predict ischemic stroke; (2) Short stature (OR 0.93, 95% CI 0.91-0.95, p<0.001) along with left atrial (LA) anterior-posterior diameter and diastolic mitral inflow velocity (E) to diastolic mitral annuls velocity (E') (E/E') were independent predictor of stroke; (3) Height showed inverse correlation with E/E' independently, even after adjusting for other variables, including age, sex, and body weight, and comorbidities β -0.20, p=0.003); (4) LA size showed no correlation with stature (R=-0.06, p=0.18), whereas left ventricular size increases according to height of patients.</AbstractText>Short stature is associated with occurrence of ischemic stroke and diastolic dysfunction in patients with AF and preserved systolic function. Height is a non-modifiable risk factor of stroke and might be more important than obesity in Asian AF patients, who are relatively thinner than western populations.</AbstractText>Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.</CopyrightInformation> |
11,858 | Postcardioplegia ventricular fibrillation: no impact on subsequent survival. | At aortic declamping after cardioplegic cardiac arrest, the initial rhythm can be broadly classified as ventricular fibrillation (VF) or non-VF. VF can be treated with potassium-induced conversion and direct-current countershock is only applied if potassium treatment fails. We aimed to investigate whether there are any differences between these groups of patients in regard to outcomes.</AbstractText>From January 1999 through December 2010, 12,113 patients underwent various types of cardiac surgery. Data from every patient were consecutively registered. Survival was established through the Norwegian National Registry. Cox multivariable modeling with adjustment for clinical, biochemical, and medication baseline data was used for survival analysis.</AbstractText>The mean follow-up time was 7.4 years and total patient-years were 89,268. The percentage of all-cause deaths was 24.9. Adjusted survival for patients with no postcardioplegia VF (n = 9723) and patients with successful potassium-induced conversion (n = 1877) was completely identical. Four hundred patients with electrical conversion after failed potassium treatment had a nonsignificant trend toward an increased mortality (hazard ratio, 95% confidence interval: 1.19 (0.99-1.4); p = 0.07).</AbstractText>This is the first study reporting the association between postcardioplegia VF, its treatment with potassium and outcome. No impact was found on outcome as judged by all-cause mortality.</AbstractText> |
11,859 | Combination therapy of cilostazol and bepridil suppresses recurrent ventricular fibrillation related to J-wave syndromes. | Brugada syndrome and idiopathic ventricular fibrillation (VF) associated with inferolateral early repolarization patterns are termed "J-wave syndromes." In such patients, an implantable cardioverter-defibrillator (ICD) is first-line therapy for prevention of sudden cardiac death. However, frequent ICD shocks due to recurrent VF remain serious problems.</AbstractText>The purpose of this study was to ascertain if combination therapy of cilostazol and bepridil could suppress recurrent VF.</AbstractText>We enrolled 7 patients with J-wave syndromes who experienced ICD shocks due to recurrent VF after ICD implantation. At first, cilostazol was instituted. In all subjects, palpitations due to sinus tachycardia caused by cilostazol were symptomatic. Addition of bepridil attenuated cilostazol-induced palpitations and maintained the suppressive effect of cilostazol against VF (87 ± 12 bpm to 66 ± 7 bpm, P < .01).</AbstractText>Six patients remained free of VF. Three patients underwent replacement of the ICD generator 4-5 years after ICD placement. Cilostazol was discontinued 2 days before replacement because of its antiplatelet effects. In all 3 patients, temporary discontinuation of cilostazol led to the reappearance of J waves, culminating in VF and an appropriate ICD shock in 1 patient. J waves disappeared with reinstitution of cilostazol.</AbstractText>These data suggest that combination therapy of cilostazol and bepridil may be effective and safe in suppressing VF recurrence in some cases of J-wave syndromes.</AbstractText>Copyright © 2014 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.</CopyrightInformation> |
11,860 | Implantable cardioverter defibrillator system with floating atrial sensing dipole: a single-center experience. | The concept of a single-lead dual-chamber implantable cardioverter defibrillator (ICD) with floating sensing atrial dipole has been proven safe and functional. We report a single-center experience with this ICD system; the major focus of the work is on the recorded atrial activation and its stability on a medium term follow-up.</AbstractText>Thirteen patients received a DX ICD (BIOTRONIK SE & Co, Berlin, Germany) with the Linox Smart S DX(ProMRI) ICD lead; the implantation data were reported. Daily P- and R-wave sensing amplitude was collected and followed up during 200 days; their coefficient of variance (CV) was calculated. In addition, all the atrial and ventricular high-rate episodes were analyzed.</AbstractText>The total x-ray exposure time was 3.9 ± 1.8 minutes. The overall mean sensing was 4.2 ± 1.9 mV for P wave and 12.9 ± 4.5 mV for R wave. The CV was significantly higher for the P-wave amplitude than for the R-wave one (0.25 ± 0.11 vs 0.08 ± 0.06; P < 0.001). A total of 27 high ventricular rate episodes were recorded and correctly discriminated by the device. Fifty-six high atrial rate episodes were recorded, 49 were true arrhythmic events.</AbstractText>The single-lead ICD system with floating atrial dipole provides reliable atrial sensing amplitude over time. The physician, without the implantation of an additional lead, has the atrial information that may be used for the discrimination of supraventricular tachyarrhythmia/ventricular tachycardia, for the early detection of atrial fibrillation episodes and for the evaluation of changes in the patient's heart status.</AbstractText>©2014 Wiley Periodicals, Inc.</CopyrightInformation> |
11,861 | Sudden cardiac arrest at the finish line: in coronary ectopia, the cause of ischemia is from intramural course, not ostial location. | A 26-year-old woman, a well-trained runner, had a sudden cardiac arrest just before crossing the finish line of a marathon. She was rapidly resuscitated and was later found to have an ectopic origin of the left coronary artery. This anomaly was surgically repaired by translocating the ostium from the right to the left sinus of Valsalva. Her difficult postoperative course prompted further coronary evaluation, which revealed severe stenosis of the neoostium. The patient underwent a second operation: this time, the stenosis was bypassed via a left internal mammary artery-to-left anterior descending coronary artery (LAD) graft. Hypoplasia of the LAD and spasm during manipulation caused the graft to fail, necessitating double-stent angioplasty of the left main ostium and the LAD 2 months later. At the patient's 6-month follow-up examination, she had no further evidence of functional ischemia, and she resumed jogging. Because the mode and mechanism of the patient's condition and events were documented in unusual detail, this case furthers our understanding of sudden cardiac arrest in athletes who have rare coronary anomalies. We conclude that ectopia of a coronary artery does not itself cause potentially fatal ischemia. Rather, these events are due to the ectopic artery's intramural proximal course within the aortic media, which might result in critical stenosis by means of hypoplasia or lateral compression of the artery. |
11,862 | Takotsubo cardiomyopathy as a sequela of elective direct-current cardioversion for atrial fibrillation. | In takotsubo cardiomyopathy, the clinical appearance is that of an acute myocardial infarction in the absence of obstructive coronary artery disease, with apical ballooning of the left ventricle. The condition is usually precipitated by a stressful physical or psychological experience. The mechanism is unknown but is thought to be related to catecholamine excess. We present the case of a 67-year-old woman who experienced cardiogenic shock caused by takotsubo cardiomyopathy, immediately after undergoing elective direct-current cardio-version for atrial fibrillation. After a course complicated by left ventricular failure, cardiogenic shock, and ventricular tachycardia, she made a complete clinical and echocardiographic recovery. In addition to this case, we discuss the possible direct effect of cardioversion in takotsubo cardiomyopathy. |
11,863 | Bileaflet versus posterior-leaflet-only preservation in mitral valve replacement. | In the present study of mitral valve replacement, we investigated whether complete preservation of both leaflets (that is, the subvalvular apparatus) is superior to preservation of the posterior leaflet alone. Seventy patients who underwent mitral valve replacement in our clinic were divided into 2 groups: MVR-B (n=16), in whom both leaflets were preserved, and MVR-P (n=54), in whom only the posterior leaflet was preserved. The preoperative and postoperative clinical and echocardiographic findings were evaluated retrospectively. No signs of left ventricular outflow tract obstruction were observed in either group. In the MVR-B group, no decrease was observed in left ventricular ejection fraction during the postoperative period, whereas a significant reduction was observed in the MVR-P group (P=0.003). No differences were found between the 2 groups in their need for inotropic agents or intra-aortic balloon pump support, or in cross-clamp time, duration of intensive care unit or hospital stays, postoperative development of new atrial fibrillation, or mortality rates. Bileaflet preservation prevented the decrease in left ventricular ejection fraction that usually followed preservation of the posterior leaflet alone. However, posterior leaflet preservation alone yielded excellent results in terms of decreased left ventricular diameter. Bileaflet preservation should be the method of choice to prevent further decreases in ejection fraction and to avoid death in patients who present with substantially impaired left ventricular function. |
11,864 | Distinctive patterns of dominant frequency trajectory behavior in drug-refractory persistent atrial fibrillation: preliminary characterization of spatiotemporal instability. | The role of substrates in the maintenance of persistent atrial fibrillation (persAF) remains poorly understood. The use of dominant frequency (DF) mapping to guide catheter ablation has been proposed as a potential strategy, but the characteristics of high DF sites have not been extensively studied. This study aimed to assess the DF spatiotemporal stability using high density noncontact mapping (NCM) in persAF.</AbstractText>Eight persAF patients were studied using NCM during AF. Ventricular far-field cancellation was performed followed by the calculation of DF using Fast Fourier Transform. Analysis of DF stability and spatiotemporal behavior were investigated including characteristics of the highest DF areas (HDFAs). A total of 16,384 virtual electrograms (VEGMs) and 232 sequential high density 3-dimensional DF maps were analyzed. The percentage of DF stable points decreased rapidly over time. Repetition or reappearance of DF values were noted in some instances, occurring within 10 seconds in most cases. Tracking the HDFAs' center of gravity revealed 3 types of propagation behavior, namely (i) local, (ii) cyclical, and (iii) chaotic activity, with the former 2 patterns accounting for most of the observed events.</AbstractText>DF of individual VEGMs was temporally unstable, although reappearance of DF values occurred at times. Hence, targeting sites of 'peak DF' from a single time frame is unlikely to be a reliable ablation strategy. There appears to be a predominance of local and cyclical activity of HDFAs hinting a potentially nonrandom temporally periodic behavior that provides further mechanistic insights into the maintenance of persAF.</AbstractText>© 2013 Wiley Periodicals, Inc.</CopyrightInformation> |
11,865 | Predictors for cardiac resynchronization therapy response: the importance of QRS morphology and left ventricular lead position. | Although cardiac resynchronization therapy (CRT) is a well-established treatment for a subset of patients with chronic heart failure, a considerable proportion of eligible patients still fail to benefit from this treatment. The aim of this study was to identify potential independent predictors for being a responder to CRT. A single-center, retrospective analysis was conducted in 193 consecutive patients with heart failure and wide QRS complex who successfully underwent CRT device implantation from January 2006 to October 2012. Clinical characteristics, left ventricular lead position (LV-Ps), electrocardiography and echocardiography were evaluated before and 12 months after CRT. Response to CRT was defined as an absolute increase of ≥ 5% in left ventricular ejection fraction (LVEF) compared with baseline at 12 months after CRT implantation without heart failure rehospitalization or any cause of death. There were 132 responders (68%) and 61 nonresponders (32%). By univariate logistic analysis, the presence of non-left bundle branch block (non-LBBB) and QRS duration, chronic atrial fibrillation (AF), history of ventricular tachycardia (VT), degree of tricuspid regurgitation and left atrium dimension (LAD) at baseline, ΔQRS duration, and LV-Ps were associated with predicting a response to CRT. However, on multivariate analysis, only optimal LV-Ps and presence of non-LBBB remained independently predictive for a CRT response, with an odds ratio of 2.53 (95% confidence interval [CI]: 1.13-5.66, P = 0.023), 0.15(95% CI: 0.05-0.45, P = 0.001), respectively. Kaplan-Meier analysis revealed that patients with nonoptimal LV-Ps or non-LBBB morphology had a significantly higher rate of mortality or heart failure rehospitalization as compared with those with optimal LV-Ps or LBBB morphology (P < 0.05). |
11,866 | Atrial fibrillation burden in Myotonic Dystrophy type 1 patients implanted with dual chamber pacemaker: the efficacy of the overdrive atrial algorithm at 2 year follow-up. | The role that atrial pacing therapy plays on the atrial fibrillation (AF) burden is still unclear. Aim of the study was to evaluate the effect of the atrial preference pacing algorithm on AF burden in patients affected by Myotonic Dystrophy type 1 (DM1) followed for a long follow up period. Sixty DM1 patients were -implanted with a dual chamber pacemaker (PM) for first degree or symptomatic type 1/type 2 second degree atrio-ventricular blocks- were followed for 2-years after implantation, by periodical examination. After 1 month of stabilization, they were randomized into two groups: 1) Patients implanted with conventional dual-chamber pacing mode (DDDR group) and 2) Patients implanted with DDDR plus Atrial Preference Pacing (APP) algorithm (APP ON group). The results showed that atrial tachycardia (AT)/AF burden was significantly reduced at 1 year follow up in the APP ON group (2122 ± 428 minutes vs 4127 ± 388 minutes, P = 0.03), with a further reduction at the end of the 2 year follow up period (4652 ± 348 minutes vs 7564 ± 638 minutes, P = 0.005). The data here reported show that the APP is an efficient algorithm to reduce AT/AF burden in DM1 patients implanted with dual chamber pacemaker. |
11,867 | Factors responsible for elevated plasma B-type natriuretic peptide levels in severe aortic stenosis: comparison between elderly and younger patients. | Elevated plasma B-type natriuretic peptide (BNP) is a predictor of outcome and helpful for risk stratification in aortic stenosis (AS). However, left ventricular (LV) diastolic dysfunction progresses with aging and may also influence plasma BNP levels in elderly patients. We hypothesized that plasma BNP levels may be influenced by age in severe AS, and that factors that affect the elevation of plasma BNP levels may be different between elderly and younger patients with AS.</AbstractText>We performed echocardiography in 341 patients with severe AS [aortic valve area (AVA)<1.0cm(2)] and classified them into two groups by age (elderly ≥75 years old, n=201; younger patients <75 years old, n=140). We used multivariate linear regression analysis to assess the factors that determine plasma BNP levels in both groups.</AbstractText>Age was found to be one of the independent determinants of plasma BNP levels in all patients (β=0.135, p=0.005). Although AVA was similar in the two groups, plasma BNP levels and E/e' were significantly higher in elderly than younger patients [133.0 (IQR, 73.3-329.7)pg/dl vs 92.8 (IQR, 40.6-171.8)pg/dl, p<0.01; 20±8 vs 16±6, p<0.01, respectively). In multivariate stepwise linear regression analysis, AVA index, LV ejection fraction, mass index, E/e', estimated systolic pulmonary artery pressure (eSPAS), and the presence of atrial fibrillation were independent determinants of plasma BNP levels in younger patients. In contrast, the independent determinants of plasma BNP levels in elderly patients were LV ejection fraction, mass index, E/e', eSPAS, the presence of atrial fibrillation, age, and hemoglobin levels, but not AVA index.</AbstractText>There may be differences in the factors that influence plasma BNP levels between elderly and younger patients with severe AS. In elderly patients, plasma BNP levels may be influenced more by these factors than AS severity compared with younger patients.</AbstractText>Copyright © 2014 Japanese College of Cardiology. Published by Elsevier Ltd. All rights reserved.</CopyrightInformation> |
11,868 | Postresuscitation hemodynamics during therapeutic hypothermia after out-of-hospital cardiac arrest with ventricular fibrillation: a retrospective study. | To evaluate the incidence of postresuscitation myocardial depression (PRMD) and hemodynamical parameters associated with PRMD in patients treated with therapeutic hypothermia (TH) after out-of-hospital cardiac arrest with ventricular fibrillation (OHCA-VF).</AbstractText>Analysis of hemodynamical data from computerized clinical databases of two academic ICUs during two year period. We analyzed hemodynamical data from a subgroup of patients with pulmonary artery catheter (PAC). We defined PRMD as a cardiac index (CI) less than 1.5l/(minm(2)) any time during the first 12h and compared clinical variables and hemodynamical parameters in patients with or without PRMD.</AbstractText>Of 120 included patients PAC monitoring was used in 47 (39%). Of 47, 31 (66%, 95% CI 52% to 80%) developed PRMD. There was no difference in urinary output, lactate, mean arterial or central venous pressures or mixed venous saturation between patients with or without PRMD. Low CI was reversed with dobutamine infusion. Presence or absence PRMD was not associated with 6-month neurological outcome.</AbstractText>Two-thirds of the OHCA-VF patients develops transient postresuscitation myocardial depression not easily detected without monitoring of CI during therapeutic hypothermia. Further controlled studies are warranted to evaluate the value of different hemodynamic targets and monitoring after cardiac arrest in terms of outcome.</AbstractText>Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.</CopyrightInformation> |
11,869 | Incidence and prognostic significance of silent atrial fibrillation in acute myocardial infarction. | Silent atrial fibrillation (AF) has been suggested to be frequent after acute myocardial infarction (MI). Continuous ECG monitoring (CEM) has been shown to improve AF screening in patients at risk of stroke.</AbstractText>We aimed to assess the incidence and prognosis of silent AF in patients with acute MI.</AbstractText>All the consecutive patients with acute MI were prospectively analyzed by CEM ≥ 48 h after admission. Silent AF was defined as asymptomatic episodes lasting at least 30s. The population was divided into three groups: no-AF, silent AF and symptomatic AF.</AbstractText>Among the 849 patients, 135 (16%) developed silent AF and 45 (5%) symptomatic AF. Compared with the no-AF group, patients with silent AF were markedly older (80 vs. 62 y, p<0.001), more frequently women (43% vs. 30%, p=0.006) and less likely to be smokers (20% vs. 36%, p<0.001). They had impaired left ventricular ejection fraction (LVEF) and left atrial (LA) enlargement. By multivariate analysis, age, history of AF, indexed LA area and LVEF were identified as independent predictors of silent AF. In-hospital heart failure and death rates were markedly higher in silent AF group when compared with no-AF patients (41.8% vs 21.0% and 10.4% vs. 1.3%, respectively).</AbstractText>Our large prospective study showed for the first time that silent AF is more frequent than symptomatic AF after MI. Our work suggests that indexed LA area could help to predict the risk of developing silent AF. Moreover, the onset of silent AF is associated with worse hospital prognosis.</AbstractText>Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.</CopyrightInformation> |
11,870 | Elevated brain natriuretic peptide level in patients undergoing atrial fibrillation ablation: is it a predictor of failed ablation or a mere function of atrial rhythm and rate at a point in time? | Pre- and postablation atrial fibrillation (AF) brain natriuretic peptide (BNP) levels were shown to predict increased recurrence of AF following ablation.</AbstractText>Our objective was to assess whether elevated BNP levels merely represent the presence of AF at the time of measurement or indeed the true recurrence of AF.</AbstractText>In a prospective study of 88 patients undergoing AF ablation, BNP levels were measured immediately before, after, 24 h, and 4-6 months postablation. BNP levels were stratified by presenting rhythm and ventricular rate at the time of measurement. Median BNP level preablation was higher in patients presenting in AF compared to sinus rhythm (SR) (54(44-79) pg/ml vs. 30(18-47) pg/ml, p < 0.001). Postablation restoration of SR in patients presenting in AF reduced median BNP levels from 54(44-79) pg/ml to 40(37-51) pg/ml, (p < 0.001). However, no change was noted in patients who presented in and maintained SR throughout the procedure (30(18-47) pg/ml to 27(16-40) pg/ml, p = 0.270). At 4-6 months, BNP measured in patients in SR was not significantly different from postablation BNP (35(22-53) pg/ml vs. 38(20-52) pg/ml, p = 0.656), although 35% of them had AF recurrence in 1-year follow-up. Median BNP level measured in five patients while in atrial arrhythmia was elevated compared to postablation BNP (464(421-464) pg/ml to 37(36-37) pg/ml, p = 0.043). BNP levels and ventricular rates are positively correlated at all times pre- and postablation.</AbstractText>BNP level rises acutely during AF and with rapid ventricular rates. BNP level seems to be a function of atrial rhythm and ventricular rate rather than short- or long-term predictor of AF ablation success.</AbstractText> |
11,871 | Implantable cardioverter defibrillator during laser transurethral resection of the prostate. |   Implantable cardioverter defibrillators have been instrumental in the health and safety of patients who are at increased risk of sudden death by ventricular tachycardia or fibrillation. Consensus on the perioperative management of cardiovascular implantable electronic devices has suggested that certain surgical interventions (including transurethral resection of the prostate) may interfere with the sensing capability of the device, thereby resulting in unforeseen adverse outcomes. However, improvements in the implantable cardioverter defibrillators have made it less susceptible to surgical interference. In addition, current guidelines recommend deactivation of the implantable cardioverter defibrillators to an asynchronous mode prior to most surgical interventions. We present the first two case reports in which implantable cardioverter defibrillators were not deactivated prior to GreenLight 180-W XPS laser-guided transurethral resection of the prostate. We left the implantable cardioverter defibrillators activated to allow them to detect and treat lethal arrhythmias by direct rather than extrinsic cardioversion. There was no cardiac arrhythmia incident in these two cases. Laser technology is not a documented source of electromagnetic interference in patients with implantable cardioverter defibrillators. There is no current evidence that links lasers to implantable cardioverter defibrillators malfunction. With increasing numbers of patients with implantable cardioverter defibrillators undergoing many different laser surgical procedures, further studies are warranted to analyze in depth the effects of laser therapy on implantable cardioverter defibrillators function and update in current guidelines. |
11,872 | New insights into defibrillation of the heart from realistic simulation studies. | Cardiac defibrillation, as accomplished nowadays by automatic, implantable devices, constitutes the most important means of combating sudden cardiac death. Advancing our understanding towards a full appreciation of the mechanisms by which a shock interacts with the heart, particularly under diseased conditions, is a promising approach to achieve an optimal therapy. The aim of this article is to assess the current state-of-the-art in whole-heart defibrillation modelling, focusing on major insights that have been obtained using defibrillation models, primarily those of realistic heart geometry and disease remodelling. The article showcases the contributions that modelling and simulation have made to our understanding of the defibrillation process. The review thus provides an example of biophysically based computational modelling of the heart (i.e. cardiac defibrillation) that has advanced the understanding of cardiac electrophysiological interaction at the organ level, and has the potential to contribute to the betterment of the clinical practice of defibrillation. |
11,873 | Heart rate turbulence for predicting new-onset atrial fibrillation in patients undergoing coronary artery bypass grafting. | Cardiac autonomic dysfunction reportedly contributes to the AF triggering and maintenance. Heart rate turbulence (HRT) is a promising noninvasive measure of cardiac autonomic function. We investigated whether ambulatory ECG-based HRT measurement could predict in-hospital new-onset atrial fibrillation (AF) after coronary artery bypass graft (CABG) surgery.</AbstractText>HRT onset (TO) and slope (TO) were prospectively measured from 24-h Holter recording in 113 consecutive patients prior to CABG. Abnormal HRT was defined as at least one abnormal value in TO (> 0%) and TS (< 2.5 ms/RR).</AbstractText>Patients with abnormal HRT (n = 60) showed a significantly higher AF incidence (47% versus 21%, P = 0.005) and AF burden (29 ± 9 versus 7 ± 5 h, P = 0.043) than those with normal HRT (n = 53). Abnormal HRT were identified as independent predictors for the new-onset postoperative AF. During the follow-up period (12.0 ± 10.5 months), the abnormal HRT group showed a worse prognosis versus the normal HRT group regarding the AF recurrence/postoperative stroke (P = 0.018). Additionally, the postoperative AF incidence, in-hospital AF burden, and the rate of AF recurrence/postoperative stroke gradually elevated as the number of abnormal HRT values increased from 0 to 2.</AbstractText>Preoperative abnormal HRT was significantly associated with worse short-term (in-hospital new-onset AF) and long-term outcomes (post-discharge AF recurrence/postoperative stroke) after CABG surgery. Additional studies incorporating preventive interventions depending on the preoperative HRT results might be worthwhile in this patient group.</AbstractText>Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.</CopyrightInformation> |
11,874 | Adverse effects of first-degree AV-block in patients with sinus node dysfunction: data from the mode selection trial. | Patients with a pacing indication and first-degree atrioventricular (AV)-block pose a clinical challenge. The prognostic impact of first-degree AV-block in patients with sinus node dysfunction and the impact of pacing in this setting are not known.</AbstractText>In the Mode Selection Trial (MOST), 2,010 patients with sinus node dysfunction were randomized to either dual-chamber (DDD-R) or ventricular (VVI-R) pacing and followed for a median of 33 months. We report on clinical outcomes in patients with first-degree AV-block (PR interval > 200 ms) compared with patients who had a normal PR interval at baseline.</AbstractText>Patients with first-degree AV-block (n = 378) were older (median [Q1, Q3]; 76 [70, 82] years vs 73 [66, 79] years, P< 0.0001), more often male (57% vs 49%, P = 0.0049), and had more comorbidity, such as hypertension (66% vs 60%, P = 0.034) and heart failure (24% vs 17%, P = 0.0050) than patients with normal AV-conduction (n = 1,159). In multivariable analyses, patients with first-degree AV-block were at greater risk of death, stroke, or heart failure hospitalization (hazard ratio [HR] 1.31, 95% confidence interval [CI] 1.06-1.61, P = 0.013). A trend towards a higher incidence of atrial fibrillation was seen (HR 1.24, 95% CI 0.98-1.55, P = 0.069). No significant interactions between pacing arm and prolonged versus normal PR were found for any endpoint, and hazard ratios were consistent across subgroups.</AbstractText>First-degree AV-block is associated with more advanced disease but is still an independent predictor of poor clinical outcome. Neither DDD-R nor VVI-R pacing, as employed in MOST, eliminate the negative effects associated with first-degree AV-block.</AbstractText>©2014 Wiley Periodicals, Inc.</CopyrightInformation> |
11,875 | Clinical benefit of cardiac resynchronization therapy with a defibrillator in patients with an ejection fraction > 35% estimated by cardiac magnetic resonance. | Cardiac resynchronization therapy with a defibrillator prolongs survival and improves quality of life in advanced heart failure. Traditionally, patients with ejection fraction > 35 estimated by echocardiography have been excluded. We assessed the prognostic impact of this therapy in a group of patients with severely depressed systolic function as assessed by echocardiography but with an ejection fraction > 35% as assessed by cardiac magnetic resonance.</AbstractText>We analyzed consecutive patients admitted for decompensated heart failure between 2004 and 2011. The patients were in functional class II-IV, with a QRS ≥ to 120 ms, ejection fraction ≤ 35% estimated by echocardiography, and a cardiac magnetic resonance study. We included all patients (n=103) who underwent device implantation for primary prevention. Ventricular arrhythmia, all-cause mortality and readmission for heart failure were considered major cardiac events. The patients were divided into 2 groups according to systolic function assessed by magnetic resonance.</AbstractText>The 2 groups showed similar improvements in functional class and ejection fraction at 6 months. We found a nonsignificant trend toward a higher risk of all-cause mortality in patients with systolic function ≤ 35% at long-term follow-up. The presence of a pattern of necrosis identified patients with a worse prognosis for ventricular arrhythmias and mortality in both groups.</AbstractText>We conclude that cardiac resynchronization therapy with a defibrillator leads to a similar clinical benefit in patients with an ejection fraction ≤ 35% or > 35% estimated by cardiac magnetic resonance. Analysis of the pattern of late gadolinium enhancement provides additional information on arrhythmic risk and long-term prognosis.</AbstractText>Copyright © 2013 Sociedad Española de Cardiología. Published by Elsevier Espana. All rights reserved.</CopyrightInformation> |
11,876 | Influence of left ventricular remodeling on atrial fibrillation recurrence and cardiovascular hospitalizations in patients undergoing rhythm-control therapy. | Atrial fibrillation (AF) patients with left ventricular hypertrophy (LVH) and diastolic dysfunction may derive benefit from being in sinus rhythm but no data are available to support this strategy in them. We sought to investigate effect of left ventricular remodeling on cardiovascular outcomes in AF patients undergoing rhythm control strategy.</AbstractText>We identified 1088 patients with echocardiographic data on left ventricular mass (LVM) enrolled in the AFFIRM trial. Using the American Society of Echocardiography (ASE) criteria, patients were divided into 4 categories: 1) normal geometry, 2) concentric remodeling, 3) eccentric hypertrophy, and 4) concentric hypertrophy. The primary endpoint was AF recurrence and the secondary endpoint was cardiovascular hospitalization (CVH).</AbstractText>In rhythm control arm, median time to recurrence in patients with concentric LVH was 13.3 months (95% CI 8.2-24.5) vs. 28.3 months (95% CI 20.2-48.6) in patients without LVH. Concentric left ventricular hypertrophy (LVH) was independently predictive of AF recurrence (HR 1.49, 95% CI 1.10-2.01, p=0.01) in rhythm control arm, but not in overall population or rate control arm. Both concentric and eccentric LVH were independently predictive of cardiovascular hospitalization (CVH) in the overall population, with respective HRs of 1.36 (1.04-1.78, p=0.03) and 1.38 (1.02-1.85, p=0.04).</AbstractText>Concentric LVH is predictive of AF recurrences when a predominantly pharmacologic rhythm-control strategy is employed. Different patterns of LVH seem to be important determinants of outcomes (AF recurrence and CVH). These findings may have important clinical implications for the management of patients with AF and LVH. Further studies are warranted to confirm our findings.</AbstractText>Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.</CopyrightInformation> |
11,877 | Anesthesia for a child with Walker-Warburg syndrome. | Walker-Warburg Syndrome is a rare, autosomal recessive congenital muscular dystrophy manifested by central nervous system, eye malformations and possible multisystem involvement. The diagnosis is established by the presence of four criteria: congenital muscular dystrophy, type II lissencephaly, cerebellar malformation, and retinal malformation. Most of the syndromic children die in the first three years of life because of respiratory failure, pneumonia, seizures, hyperthermia and ventricular fibrillation.</AbstractText>The anesthetic management of a two-months-old male child listed for elective ventriculo-peritoneal shunt operation was discussed.</AbstractText>A careful anesthetic management is necessary due to the multisystem involvement. We reported anesthetic management of a two-months-old male child with Walker-Warburg Syndrome who was listed for elective ventriculo-peritoneal shunt operation.</AbstractText>Copyright © 2013 Sociedade Brasileira de Anestesiologia. Published by Elsevier Editora Ltda. All rights reserved.</CopyrightInformation> |
11,878 | Rotor stability separates sustained ventricular fibrillation from self-terminating episodes in humans. | This study mapped human ventricular fibrillation (VF) to define mechanistic differences between episodes requiring defibrillation versus those that spontaneously terminate.</AbstractText>VF is a leading cause of mortality; yet, episodes may also self-terminate. We hypothesized that the initial maintenance of human VF is dependent upon the formation and stability of VF rotors.</AbstractText>We enrolled 26 consecutive patients (age 64 ± 10 years, n = 13 with left ventricular dysfunction) during ablation procedures for ventricular arrhythmias, using 64-electrode basket catheters in both ventricles to map VF prior to prompt defibrillation per the institutional review board-approved protocol. A total of 52 inductions were attempted, and 36 VF episodes were observed. Phase analysis was applied to identify biventricular rotors in the first 10 s or until VF terminated, whichever came first (11.4 ± 2.9 s to defibrillator charging).</AbstractText>Rotors were present in 16 of 19 patients with VF and in all patients with sustained VF. Sustained, but not self-limiting VF, was characterized by greater rotor stability: 1) rotors were present in 68 ± 17% of cycles in sustained VF versus 11 ± 18% of cycles in self-limiting VF (p < 0.001); and 2) maximum continuous rotations were greater in sustained (17 ± 11, range 7 to 48) versus self-limiting VF (1.1 ± 1.4, range 0 to 4, p < 0.001). Additionally, biventricular rotor locations in sustained VF were conserved across multiple inductions (7 of 7 patients, p = 0.025).</AbstractText>In patients with and without structural heart disease, the formation of stable rotors identifies individuals whose VF requires defibrillation from those in whom VF spontaneously self-terminates. Future work should define the mechanisms that stabilize rotors and evaluate whether rotor modulation may reduce subsequent VF risk.</AbstractText>Copyright © 2014 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.</CopyrightInformation> |
11,879 | The role of the wearable cardioverter defibrillator in clinical practice. | The wearable cardioverter defibrillator (WCD) is an option for external monitoring and defibrillation in patients at risk for sudden cardiac arrest caused by ventricular tachycardia or ventricular fibrillation and who are not candidates for or who refuse an implantable cardioverter defibrillator (ICD). WCDs provide monitoring with backup defibrillation protection. WCDs have been used when a patient's condition delays or prohibits ICD implantation, or as a bridge when an indicated ICD must be explanted. WCDs are used for primary prevention of sudden cardiac death during high-risk gap periods early after myocardial infarction, coronary revascularization, or new diagnosis of heart failure. |
11,880 | The totally subcutaneous implantable defibrillator. | The subcutaneous implantable cardioverter-defibrillator (S-ICD) is a new therapeutic option for patients at risk of sudden cardiac arrest. The device uses a pulse generator implanted in the lateral thoracic region and a tunneled subcutaneous electrode. Benefits of this configuration include the preservation of venous access and reduction in the risk of systemic infection, vascular injury, and lead failure. Clinical trials suggest that the device effectively senses, discriminates, and converts both spontaneous and induced ventricular tachycardia and ventricular fibrillation episodes with minimal complications. The S-ICD represents a novel implantable cardioverter-defibrillator configuration that may provide reliably effective therapy for malignant tachyarrhythmias. |
11,881 | Is defibrillation testing necessary? | With advancements in implantable cardioverter defibrillator (ICD) technology, the practice of performing defibrillation threshold (DFT) testing at the time of implantation has been questioned. With availability of biphasic waveforms, active cans, and high-output devices, opponents claim that DFT testing is no longer necessary. Clinical trials demonstrating the efficacy of ICDs in prevention of sudden cardiac death have, however, all used some form of defibrillation testing. This debate is fueled by the absence of data from randomized prospective trials evaluating the role of DFT testing in predicting clinical shock efficacy or survival. This review discusses both sides of the argument. |
11,882 | Sudden cardiac arrest recorded during Holter monitoring: prevalence, antecedent electrical events, and outcomes. | Causative arrhythmias of sudden cardiac arrest (SCA) are changing in this age of improved coronary care.</AbstractText>The purpose of this study was to examine the frequency of terminal arrhythmias and the electrical events prior to SCA.</AbstractText>We analyzed 24-hour Holter recordings of 132 patients enrolled from 41 institutions who either died (n = 88) or had an aborted death (n = 44). The Holter recordings were obtained for diagnosing and evaluating diseases and arrhythmias in those without any episodes suggestive of SCA.</AbstractText>In 97 patients (73%), SCA was associated with ventricular tachyarrhythmias and in 35 (27%) with bradyarrhythmias. The bradyarrhythmia-related SCA patients were older than those with a tachyarrhythmia-related SCA (70 ± 13 years vs. 58 ± 19 years, P < .001). The most common arrhythmia for a tachyarrhythmia-related SCA was ventricular tachycardia degenerating to ventricular fibrillation (45%). The bradyarrhythmia-related SCA was caused by asystole (74%) or AV block (26%). Spontaneous conversion was observed in 37 patients (38%) with ventricular tachyarrhythmias. Of those, 62% of the patients experienced symptoms including syncope, chest pain, or convulsion. Multivariate logistic analysis revealed that independent predictors of mortality for tachyarrhythmia-related SCAs were advanced age (odds ratio 1.04, 95% confidence interval 1.02-1.08) and ST elevation within the hour before SCA (odds ratio 3.54, 95% confidence interval 1.07-13.5). In contrast, the presence of preceding torsades de pointes was associated with spontaneous conversion (odds ratio 0.20, 95% confidence interval 0.05-0.66).</AbstractText>The most frequent cause of SCA remains ventricular tachyarrhythmias. Advanced age and ST elevation before SCA are risk factors for mortality in tachyarrhythmia-related SCAs.</AbstractText>Copyright © 2014 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.</CopyrightInformation> |
11,883 | Usefulness of electrocardiographic parameters for risk prediction in arrhythmogenic right ventricular dysplasia. | The value of electrocardiographic findings predicting adverse outcome in patients with arrhythmogenic right ventricular dysplasia (ARVD) is not well known. We hypothesized that ventricular depolarization and repolarization abnormalities on the 12-lead surface electrocardiogram (ECG) predict adverse outcome in patients with ARVD. ECGs of 111 patients screened for the 2010 ARVD Task Force Criteria from 3 Swiss tertiary care centers were digitized and analyzed with a digital caliper by 2 independent observers blinded to the outcome. ECGs were compared in 2 patient groups: (1) patients with major adverse cardiovascular events (MACE: a composite of cardiac death, heart transplantation, survived sudden cardiac death, ventricular fibrillation, sustained ventricular tachycardia, or arrhythmic syncope) and (2) all remaining patients. A total of 51 patients (46%) experienced MACE during a follow-up period with median of 4.6 years (interquartile range 1.8 to 10.0). Kaplan-Meier analysis revealed reduced times to MACE for patients with repolarization abnormalities according to Task Force Criteria (p = 0.009), a precordial QRS amplitude ratio (∑QRS mV V1 to V3/∑QRS mV V1 to V6) of ≤ 0.48 (p = 0.019), and QRS fragmentation (p = 0.045). In multivariable Cox regression, a precordial QRS amplitude ratio of ≤ 0.48 (hazard ratio [HR] 2.92, 95% confidence interval [CI] 1.39 to 6.15, p = 0.005), inferior leads T-wave inversions (HR 2.44, 95% CI 1.15 to 5.18, p = 0.020), and QRS fragmentation (HR 2.65, 95% CI 1.1 to 6.34, p = 0.029) remained as independent predictors of MACE. In conclusion, in this multicenter, observational, long-term study, electrocardiographic findings were useful for risk stratification in patients with ARVD, with repolarization criteria, inferior leads TWI, a precordial QRS amplitude ratio of ≤ 0.48, and QRS fragmentation constituting valuable variables to predict adverse outcome. |
11,884 | Limitations of the AutoCapture™ Pacing System in patients with cardiac stimulation devices. | AutoCapture (St Jude Medical) is a technological development that confirms ventricular capture analysing the evoked response after a pacing impulse and adjusts the energy output to changes in the stimulation threshold. Although this algorithm is aimed to assure capture minimizing energy consumption, some patients might not benefit from it. The objective of this study is to identify them.</AbstractText>Long-term AutoCapture efficiency was assessed using the data recorded in the programmer reports of patients undergoing scheduled pacemaker check-ups during 2012 in our institution. We have evaluated 160 consecutive patients (58% men) aged 78 ± 9 years. Pacemaker stimulation mode was DDD in 116 patients (72.5%) and VVI in 44 patients (27.5%). During the scheduled visits for pacemaker check-up, 73 patients (45.6%) showed abnormalities in the long-term AutoCapture function report (high variability in the AutoCapture stimulation threshold and/or out-of-range values). After multivariate analysis, abnormal AutoCapture pattern was associated to the presence of atrial fibrillation [odds ratio (OR) 3.96 (1.59-9.82; P < 0.05)]; and a ventricular pacing ≤25% of the time [OR 4.80 (2.09-11.05; P < 0.05)]. AutoCapture abnormalities were also described in three (1.8%) patients with very low stimulation threshold.</AbstractText>Although AutoCapture algorithm has shown both efficacy and safety, our findings suggest that some patients with atrial fibrillation or those requiring ventricular pacing ≤25% of the time may not benefit from it. Activation of the algorithm should be individualized according to the patient's characteristics and long-term AutoCapture pattern checked in the routine follow-up.</AbstractText>Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2014. For permissions please email: journals.permissions@oup.com.</CopyrightInformation> |
11,885 | Pseudo-ventricular tachycardia mimicking malignant arrhythmia in a patient with rapid atrial fibrillation. | Artifacts can simulate arrhythmias such as atrial flutter, atrial fibrillation, and ventricular tachycardia. A case of pseudo-ventricular tachycardia is outlined in a patient with newly diagnosed atrial fibrillation, which made the diagnosis a special challenge. Characteristic signs of pseudo-ventricular tachycardia are described. This case reinforces the importance of recognizing artifacts to avoid unnecessary interventions, especially in the telemetry and critical care units. |
11,886 | Efficacy of a new class III drug niferidil in cardioversion of persistent atrial fibrillation and flutter. | To study the efficacy and safety of the new class III antiarrhythmic agent niferidil for pharmacological cardioversion in patients with persistent atrial fibrillation (AF) and atrial flutter (AFl).</AbstractText>One hundred thirty-four adults (aged 57.8 ± 11 years, 90 males) were included with median AF duration of 3 (1.5-6) months. All patients received a total of 10-30 μg/kg, niferidil, intravenously, in 1-3 (if needed) consecutive boluses at 15-minute intervals. Holter electrocardiogram monitoring was started before infusion and was continued for 24 hours. The criterion for an antiarrhythmic effect was sinus rhythm restoration within 24 hours of the initial bolus. Niferidil converted AF to sinus rhythm in 47.7% of cases after bolus 1, in 62% of cases after bolus 2, and in 84.6% of cases bolus 3. Niferidil induced a 100% recovery rate in patients with AFl and a 91.8% recovery rate in patients with AF of duration from 8 days to 3 months. Nonsustained torsade de pointes occurred in 1 patient (0.7%), and nonsustained monomorphic ventricular tachycardia was observed in 5 patients (3.7%).</AbstractText>The new intravenous class III drug niferidil demonstrated high conversion rates of 84.6% in patients with persistent AF and 100% in patients with persistent AFl. Niferidil may be used as a possible alternative to electrical cardioversion for pharmacological cardioversion of persistent AF/AFl.</AbstractText> |
11,887 | Prevalence and clinical correlation of left ventricular systolic dysfunction in african americans with ischemic stroke. | The goal of the present study was to determine the prevalence of left ventricular systolic dysfunction (LVSD) and associated clinical correlates in African Americans (AA) diagnosed with ischemic stroke (IS).</AbstractText>Retrospective chart analysis was done on all diagnosed AA IS patients between January 2010 and March 2012. Patients with atrial fibrillation were excluded. A total of 147 patients were included in the study. Transthoracic 2-dimensional echocardiography was used to assess left ventricular systolic function, and study groups were categorized as normal, mild, moderate, and severely abnormal, based on the ejection fraction (EF). Available imaging studies were analyzed for data collection. Logistic regression and Pearson chi-square tests were performed.</AbstractText>Normal EF was present in 114 of 147 patients (78%). Mild abnormality was present in 9 of 147 (6%), moderate in 8 of 147 (5%), and severe in 16 of 147 (11%) patients. In patients with mildly reduced EF, smoking was the most common (RF). In patients with moderately and severely reduced EFs, hypertension was the most common RF. History of smoking was commonly found in systolic dysfunction group compared with normal group (P = .001). Logistic regression analysis revealed that smoking and advanced age were the significant predictors for LVSD. Large-vessel IS were more common in systolic dysfunction group than normal EF group (P = .017).</AbstractText>Prevalence of LVSD in AA with IS was 22% in our study. Smoking was a significant modifiable RF associated with systolic dysfunction. A history of smoking and higher age could predict the occurrence of LVSD. There were more large-vessel IS in patients with LVSD.</AbstractText>Copyright © 2014 National Stroke Association. Published by Elsevier Inc. All rights reserved.</CopyrightInformation> |
11,888 | Hemodynamic-directed cardiopulmonary resuscitation during in-hospital cardiac arrest. | Cardiopulmonary resuscitation (CPR) guidelines assume that cardiac arrest victims can be treated with a uniform chest compression (CC) depth and a standardized interval administration of vasopressor drugs. This non-personalized approach does not incorporate a patient's individualized response into ongoing resuscitative efforts. In previously reported porcine models of hypoxic and normoxic ventricular fibrillation (VF), a hemodynamic-directed resuscitation improved short-term survival compared to current practice guidelines. Skilled in-hospital rescuers should be trained to tailor resuscitation efforts to the individual patient's physiology. Such a strategy would be a major paradigm shift in the treatment of in-hospital cardiac arrest victims. |
11,889 | Is recent cannabis use associated with acute coronary syndromes? An illustrative case series. | Cannabis is a frequently used recreational drug that potentially imposes serious health problems. We report three cases where recent and/or chronic use of marijuana led to severe cardiac dysfunction. All three patients collapsed at home and required cardiopulmonary resuscitation (CPR) with initial restoration of spontaneous circulation (ROSC). The mechanism of the cardiovascular collapse was different in each case. The first case presented with asystole and was found to have diffuse coronary vasospasm on coronary angiography in the hours after acute cannabis abuse. In the second case, an acute anterior infarction with occlusion of both the right coronary artery (RCA) and the left anterior descendens (LAD) was observed in a young patient without known cardiovascular risks but with chronic cannabis abuse. The third case presented at home with ventricular fibrillation presumably caused by an acute coronary syndrome due to left anterior descending (LAD) artery occlusion. The hetero-anamnesis of the family reported that all three patients had recently used cannabis. Toxicological screening also showed no other substance abuse than cannabis. Using these three cases, we would like to illustrate that the widespread use of cannabis is not as innocent as is believed. Cannabis use can lead to severe cardiovascular problems and sudden death, not only in people at increased cardiovascular risk, but also in young people without any medical history or risk factors. |
11,890 | Outcome comparison of African-American and Caucasian patients with severe aortic stenosis subjected to transcatheter aortic valve replacement: a single-center experience. | This study aimed to report the outcomes of African Americans (AAs) in the US undergoing transcatheter aortic valve replacement (TAVR) for severe aortic stenosis (AS).</AbstractText>Compared to Caucasians, AAs are reported to have poorer outcomes from most cardiovascular diseases, including high complication rates after surgical aortic valve replacement. The outcomes of AAs undergoing TAVR are not well established.</AbstractText>Consecutive patients who underwent TAVR were included in this analysis. Patients' baseline characteristics, procedural data, in-hospital- and long-term outcomes were recorded and a comparison was performed between the AA and Caucasian cohorts.</AbstractText>In a cohort of 469 consecutive patients, 51 (10.8%) were AA and 345 (74.5%) were Caucasian. The remaining patients (n = 73; 15.3%) self-reported their race as "unknown" or were from other races. Most baseline characteristics were similar between the two groups except for less men (33.3 vs. 50.1%; P = 0.016), a lower mean left ventricular ejection fraction (48.85 ± 16.35 vs. 53.24 ± 13.41%; P = 0.04) and lower rates of atrial fibrillation in AAs (15.7 vs.45.4%; P < 0.001). TAVR procedures in AAs were less frequently performed as part of a clinical trial (60.8 vs. 76.8%; P = 0.014). Most procedural and periprocedural outcome parameters were similar save for a higher rate of hemodynamic instability and postoperative need for intubation in AAs (10.4 vs. 2.5%; P = 0.018 and 29.4 vs. 16.9%; P = 0.03, respectively). This did not translate into a difference in mortality between AAs and Caucasians (30-day mortality 9.8 vs. 9.9%; P = 0.99; 1-year mortality 19.6 vs. 24.3%; P = 0.458, respectively).</AbstractText>Unlike with other cardiovascular interventions, this study demonstrates that AA patients referred for TAVR shared similar risks and outcomes when compared to a Caucasian population.</AbstractText>© 2014 Wiley Periodicals, Inc.</CopyrightInformation> |
11,891 | Incidence of syncope and cardiac arrest in patients with severe aortic stenosis. |  Syncope and sudden cardiac arrest are known complications of aortic stenosis (AS).</AbstractText> The aim of the study was to investigate the incidence of these complications in patients with severe symptomatic AS and to analyze whether basic clinical data and electrocardiographic (ECG) and echocardiographic parameters can be the markers of these complications.</AbstractText> The incidence of syncope and sudden cardiac arrest and its correlations with clinical and diagnostic data (ECG, echocardiography, Holter monitoring) were analyzed in 514 patients (mean age, 60 ±11 y) with severe symptomatic AS before valve replacement.</AbstractText> Syncope was reported in 167 patients (32%), and aborted cardiac arrest in 14 (2.7%; ventricular fibrillation, 13 patients; third-degree atrioventricular block, 1 patient). None of the analyzed parameters was related to syncope. Patients with a history of sudden cardiac arrest had higher New York Heart Association class (P = 0.01), more frequent history of syncope (P = 0.017), higher left ventricular mass index (P = 0.02), lower ejection fraction (P = 0.004), longer QRS duration (P = 0.048), corrected QT (P = 0.002), QT dispersion (P = 0.007), and a higher number of ventricular arrhythmias in 24-hour Holter monitoring (P = 0.002). A multivariate analysis showed correlations between syncope, ejection fraction of less than 45%, and QTd exceeding 60 ms and aborted cardiac arrest. At least 2 of these parameters were observed in 8 of 14 patients (P <0.001): sensitivity, 57%; specificity, 86%; positive predictive value, 10%; and negative predictive value, 98%.</AbstractText> The incidence of sudden cardiac arrest in severe symptomatic AS is low. It is higher in patients with a history of syncope, prolongation of QTd, and reduced ejection fraction. None of the clinical and diagnostic parameters were associated with a history of syncope in patients with AS.</AbstractText> |
11,892 | Cardiac arrhythmia and death of teenager linked to rare genetic disorder diagnosed at autopsy. | A 17-year-old male adolescent sustained cardiac arrest after participating in a wrestling match, where he was thrown down. He had no pulse, and cardiopulmonary resuscitation was immediately initiated along with application of an automatic external defibrillator. Upon arrival of emergency medical services, an electrocardiogram showed the patient to be in ventricular tachycardia, torsades, and ventricular fibrillation. The patient was ultimately transported to the hospital and, with ACLS protocol being performed, was resuscitated to a junctional rhythm with bradycardia and borderline prolonged QT. His hospital stay was characterized by refractory cardiac failure, and 2 days after the incident, a decision was made to remove him from life support. At autopsy, there were no external or internal injuries that could be considered a contributing cause of death. On external examination, observations were made about the decedent's facial features including his nose, eyes, ears, fingers, and toes. A careful review of the decedent's medical history was initiated to reveal birth defects including syndactyly of the third and fourth digit of the upper extremity as well as complete lack of dental enamel. A tentative diagnosis of oculodentodigital dysplasia was made and confirmed by genetic testing of heart muscle taken from the decedent. This case report examines the rare association of oculodentodigital dysplasia with cardiac arrhythmia as well as places emphasis on the features of the disorder that can aid in its diagnosis. |
11,893 | [Prediction of outcome of the acute period of ischemic stroke in young and middle-aged patients]. | Objectives. To find out cardiovascular risk factors and the effect of atherosclerotic lesions of carotid arteries on the level of disability of young and middle-aged patients to the end of the acute period of ischemic stroke (II). Material and methods. A study included 266 patients, aged from 25 to 59 years, with a first-ever II in the carotid system. Risk for cerebrovascular diseases (arterial hypertension, smoking, auricular fibrillation, diabetes mellitus, hypercholesterolemia, high atherogenic index, excessive body mass, hypodynamia, a family history for cerebrovascular diseases, a history of transitory ischemic attacks, heart diseases (ischemic heat disease, myocardial infarction, reduced left ventricular ejection fraction) were analyzed. Results and conclusions. The prognostic effect of previous myocardial infarction, diabetes mellitus type 2, smoking, hemodinamically significant stenosis of carotid arteries, multifocal atherosclerotic lesions in three arterial basins was found. |
11,894 | Early eplerenone treatment in patients with acute ST-elevation myocardial infarction without heart failure: the Randomized Double-Blind Reminder Study. | We aimed to assess the impact of eplerenone on cardiovascular (CV) outcomes in STEMI without known heart failure, when initiated within 24 h of symptom onset.</AbstractText>In this randomized, placebo-controlled, double-blind trial, we assigned 1012 patients with acute STEMI and without a history of heart failure to receive either eplerenone (25-50 mg once daily) or placebo in addition to standard therapy. The primary endpoint was the composite of CV mortality, re-hospitalization, or, extended initial hospital stay, due to diagnosis of HF, sustained ventricular tachycardia or fibrillation, ejection fraction ≤40%, or elevated BNP/NT-proBNP at 1 month or more after randomization. BNP elevation was defined as BNP levels or values above 200 pg/mL or NT-proBNP values above 450 pg/mL (in patients aged below 50); above 900 pg/mL (age 50-75 years) or above 1800 pg/mL (patients older than 75). After a mean follow-up of 10.5 months, the primary endpoint occurred in 92 patients (18.2%) in the eplerenone group and in 149 patients (29.4%) in the placebo group [adjusted hazard ratio (HR), 0.58; 95% confidence interval (CI), 0.45-0.76; P < 0.0001]. The primary endpoint was driven by a high BNP/NT-proBNP level (adjusted HR, 0.60; 95% CI, 0.45-0.79; P < 0.0003). Adverse event rates were similar in both groups. Serum potassium levels exceeded 5.5 mmol/L in 5.6 vs. 3.2% (P = 0.09) and were below 3.5 mmol/L in 1.4 vs. 5.6% of patients (P = 0.0002), in the eplerenone and placebo groups, respectively.</AbstractText>The addition of eplerenone during the acute phase of STEMI was safe and well tolerated. It reduced the primary endpoint over a mean 13 months follow-up mostly because of significantly lower BNP/NT-proBNP levels. Additional studies are needed to clarify the role of early use of MRAs in STEMI patients without heart failure.</AbstractText>NCT01176968.</AbstractText>Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2014. For permissions please email: journals.permissions@oup.com.</CopyrightInformation> |
11,895 | Inhibiting mitochondrial Na+/Ca2+ exchange prevents sudden death in a Guinea pig model of heart failure. | In cardiomyocytes from failing hearts, insufficient mitochondrial Ca(2+) accumulation secondary to cytoplasmic Na(+) overload decreases NAD(P)H/NAD(P)(+) redox potential and increases oxidative stress when workload increases. These effects are abolished by enhancing mitochondrial Ca(2+) with acute treatment with CGP-37157 (CGP), an inhibitor of the mitochondrial Na(+)/Ca(2+) exchanger.</AbstractText>Our aim was to determine whether chronic CGP treatment mitigates contractile dysfunction and arrhythmias in an animal model of heart failure (HF) and sudden cardiac death (SCD).</AbstractText>Here, we describe a novel guinea pig HF/SCD model using aortic constriction combined with daily β-adrenergic receptor stimulation (ACi) and show that chronic CGP treatment (ACi plus CGP) attenuates cardiac hypertrophic remodeling, pulmonary edema, and interstitial fibrosis and prevents cardiac dysfunction and SCD. In the ACi group 4 weeks after pressure overload, fractional shortening and the rate of left ventricular pressure development decreased by 36% and 32%, respectively, compared with sham-operated controls; in contrast, cardiac function was completely preserved in the ACi plus CGP group. CGP treatment also significantly reduced the incidence of premature ventricular beats and prevented fatal episodes of ventricular fibrillation, but did not prevent QT prolongation. Without CGP treatment, mortality was 61% in the ACi group <4 weeks of aortic constriction, whereas the death rate in the ACi plus CGP group was not different from sham-operated animals.</AbstractText>The findings demonstrate the critical role played by altered mitochondrial Ca(2+) dynamics in the development of HF and HF-associated SCD; moreover, they reveal a novel strategy for treating SCD and cardiac decompensation in HF.</AbstractText>© 2014 American Heart Association, Inc.</CopyrightInformation> |
11,896 | Use of therapeutic hypothermia and extracorporeal life support after an unusual response to the ajmaline challenge in a patient with Brugada syndrome. | Brugada syndrome is a cardiac disorder associated with a high risk of sudden cardiac death, especially in young subjects. The incidence and prevalence are likely underestimated. The diagnosis is based on a characteristic electrocardiography (ECG) pattern. The most commonly performed confirmatory test in cases of equivocal ECG is the intravenous ajmaline challenge. Although relatively safe, it carries the risk of ventricular arrhythmias that could potentially degenerate into a refractory electrical storm.</AbstractText>A 27-year-old man developed sustained ventricular fibrillation after ajmaline challenge. He was rescued on extracorporeal life support after 108 min of cardiopulmonary resuscitation. Extracorporeal life support allowed recovery of spontaneous circulation and resulted in a positive neurological outcome.<Learning objective:</b> This case is an example of how extracorporeal life support was instituted after prolonged and unsuccessful cardiopulmonary resuscitation resulting in a positive central neurological outcome.>.</AbstractText> |
11,897 | Device-Based Approaches to Modulate the Autonomic Nervous System and Cardiac Electrophysiology. | Alterations in resting autonomic tone can be pathogenic in many cardiovascular disease states, such as heart failure and hypertension. Indeed, autonomic modulation by way of beta-blockade is a standard treatment of these conditions. There is a significant interest in developing non-pharmacological methods of autonomic modulation as well. For instance, clinical trials of vagal stimulation and spinal cord stimulation in the treatment of heart failure are currently underway, and renal denervation has been studied recently in the treatment of resistant hypertension. Notably, autonomic stimulation is also a potent modulator of cardiac electrophysiology. Manipulating the autonomic nervous system in studies designed to treat heart failure and hypertension have revealed that autonomic modulation may have a role in the treatment of common atrial and ventricular arrhythmias as well. Experimental data on vagal nerve and spinal cord stimulation suggest that each technique may reduce ventricular arrhythmias. Similarly, renal denervation may play a role in the treatment of atrial fibrillation, as well as in controlling refractory ventricular arrhythmias. In this review, we present the current experimental and clinical data on the effect of these therapeutic modalities on cardiac electrophysiology and their potential role in arrhythmia management. |
11,898 | Use of Cardiac Resynchronisation Therapy - Change of Clinical Settings. | Current guidelines recommend cardiac resynchronisation therapy (CRT) for patients with severe left ventricular dysfunction (left ventricular ejection fraction [LVEF] ≤35 %), QRS duration of ≥120-150 ms (Class IA and IB indications) on surface electrocardiogram (ECG) and New York Heart Association (NYHA) class III or IV heart failure (HF) symptoms. Ongoing studies aim to expand the use of CRT in patients with asymptomatic or minimal symptoms left ventricular dysfunction. There have been studies that have shown benefit of CRT extended to this group of patients. There have also been different implications of the role of CRT in patients with atrial fibrillation (AF), patients with narrow QRS duration or with right bundle branch block (RBBB) on surface ECG, as well as patients with end-stage renal failure on dialysis therapy. This article aims to review the current body of evidence of expanding use of CRT in these populations. |
11,899 | Effect Of Catheter Ablation On Quality Of Life In Atrial Fibrillation. | Atrial fibrillation (AF) is the most common sustained arrhythmia seen in clinical practice, affecting approximately 1% of the overall population. While rarely life-threatening, AF is almost universally associated with increased morbidity and mortality, predominantly through an increased risk of thromboembolic events, left ventricular dysfunction, as well as significant impairments in functional capacity and health-related quality of life (HRQOL).[1-8] Improvement in HRQOL, with a secondary reduction of disability and health-care resource utilization, is one of the major therapeutic goals in the management of AF. |
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