A H Kadish

..Implantable cardioverter defibrillators (ICD) have been shown to improve survival among patients with severe left ventricular (LV) dysfunction. However, the majority of cardiac arrests occur in patients with higher ejection fractions...

..This technique has the potential to rapidly characterize repetitive activation patterns in fibrillatory rhythms and may help distinguish among different characteristics of fibrillatory rhythms...

..Cardiac contractility modulation (CCM) delivers nonexcitatory electrical signals to the heart during the absolute refractory period intended to improve contraction...

..Ambulatory cardiac telemetry could be potentially lifesaving in this group of patients...

..This study sought to determine whether the time from diagnosis to randomization was related to outcome in a clinical trial of implantable cardioverter-defibrillator (ICD) insertion in nonischemic cardiomyopathy...

..Further risk stratification studies of post-MI LVD patients will allow ICD therapy to be applied in a more cost-effective manner...

..However, the value of prophylactic implantation of an implantable cardioverter-defibrillator (ICD) to prevent sudden death in such patients is unknown...

..To determine whether menopausal hormone therapy alters the QT interval in primarily healthy postmenopausal women...

..In addition, because noise in the ST and TP segments are highly correlated and the noise measured in the ST segment is less than that in the TP segment, uniform adoption of noise measurement in the ST segment seems most appropriate...

..We postulated that a quadratic function would describe the relationship between HRV and parasympathetic effect better than a linear function...

..We compared sensing characteristics during ventricular fibrillation of simultaneously recorded dedicated and integrated bipolar electrograms...

..The impact of ICD placement and shock on health-related quality of life (HRQL) in this population is unknown...

..Atrial rate-adaptive pacing may improve cardiopulmonary reserve in patients with left ventricular dysfunction...

..To assess the efficacy and toxicity of moricizine in treating patients with serious ventricular arrhythmias and inducible sustained ventricular tachycardia...

..The random timing of noise relative to signal results in the distribution/variance of repeated measurements. Statistical strategies may be used to reduce some of this variance and may enhance the diagnostic utility of SAECG...

..The present study was designed to assess whether transvascular stimulation through the carotid artery of the dog can be used to directly stimulate the vagus nerve and increase parasympathetic tone...

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..The lack of correlation between local VFCL and refractoriness and the infrequent occurrence of epicardial reentry suggests that intramural reentry may be the primary mechanism of VF in this model...

..A natural logarithmic model provides the best approximation of the QT-RR relation with exercise, is simple to implement, and should become the preferred method of QT correction...

..The practice of equating ICD shocks with mortality is controversial and has not been validated critically...

..The recent expansion of indications for prophylactic implantable cardioverter-defibrillator (ICD) placement in subjects with nonischemic dilated cardiomyopathy has raised concerns about the cost-effectiveness of this therapy...

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..Pharmacologic and nonpharmacologic therapies are usually equally efficacious, but the risks of pharmacologic therapy are different in men and women. Atrial fibrillation may be more difficult to treat in women...

..In the Defibrillators in Non-Ischemic Cardiomyopathy Treatment Evaluation (DEFINITE) trial, a reduction in all-cause mortality was seen in men (P = .018) but not for women (P = .76)...

..We sought to determine the predictive ability of the planar QRS-T angle in patients with nonischemic cardiomyopathy and to assess QRS-T angle behavior over time...

..Here, we review the principles of a "responder analysis."..

..This may relate to imprecision of early EF because of post-MI stunning. We sought to determine if peri-MI infarct size, as measured by cardiac magnetic resonance (CMR), is superior to early EF to predict late post-MI EF...

..These parasympathetic effects may play an important role in prevention of sudden cardiac death during these periods of increased risk...

..The use of cryomapping at a temperature of -30 degrees to produce reversible lesions has been reported to improve the safety of accessory pathways ablation performed close to the normal conduction system while maintaining efficacy...

..These data support the concept that parasympathetic tone may provide a natural antiarrhythmic effect during this time...

..In this study we examine if the criteria (F waves in the frontal plane and a partially or completely regular ventricular response) can improve the diagnostic accuracy of internists...

..Atrial fibrillation (AF) is thought to be sustained by multiple reentrant wavelets or firing foci...

..Application of models of the low- and high-slope transfer functions to signal-averaged ECGs from 33 subjects showed differences in the attenuation of P and T waves relative to the QRS...

..There are no universally accepted ECG diagnostic criteria for atrial flutter (AFL), making its differentiation from "coarse" atrial fibrillation (AF) difficult...

..Ongoing clinical studies will help determine the utility of incorporating CMRI into a risk prediction algorithm...

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..The aim of this study was to explore technical issues that may affect the estimation of local activation rate during AF using DF analysis...

..These findings may provide a basis for the role of the LOM in the genesis and maintenance of atrial fibrillation...

..CONCLUSION: ST height and QTc varied among the three phases of the menstrual cycle, predominantly after double autonomic blockade. Female sex hormones that vary throughout the menstrual cycle may modulate measures of repolarization...

..Forty-five centers were included in this trial that was designed to last an estimated 4 years. Enrollment was projected to occur over 2 1/2 years with a post enrollment follow-up of 1 1/2 years...

..However, given the risk of atrioventricular block with the septal approach, the posterior approach should be the preferred initial choice...

..This study was designed to evaluate autonomic changes preceding atrial fibrillation/flutter (AF) after thoracotomy...

..The episodes resembled fusion beats but were due to bilateral bundle branch delay...

..Given that a TEE-guided approach to cardioversion is being utilized more frequently, it may be important to determine thrombus characteristics on follow-up that would be predictive of embolic events following cardioversion...

..The determinants of BP response after tachycardia onset are complex and differ in patients with SVT and VT...

..0003). In patients with IDC selected for ICD implantation, the most consistent predictor of appropriate ICD therapy was lack of beta-blocker use. Attempts should be made to administer beta blockers to these patients, if tolerated...

..The aim of this study was to determine the accuracy of automatic mode switching algorithms in patients with permanent pacemakers for the diagnosis of atrial tachyarrhythmias...

..Changes in ventricular function induced by right ventricular pacing may account for some of its associated adverse effects...

..The goal of the current study was to evaluate the accuracy of easily available clinical characteristics for the prediction of this complication...

..These tools may improve our understanding of parasympathetic reactivation after exercise and the prognostic significance of heart rate recovery...

..CONCLUSION: Multiple dominant frequency measurements and scrutiny of the time and frequency domain signals are recommended to obtain accurate and reproducible values...

..The exact mechanisms that cause ST height to be greater in young men are not yet completely understood. The purpose of the present study was to determine whether autonomic tone is responsible for age and gender differences in ST height...

..Thus, certain pathophysiological conditions that alter Ca2+ cycling kinetics, such as heart failure, might promote ventricular arrhythmias by exaggerating these cellular heterogeneities in Ca2+ signaling...

..We sought to evaluate whether statins were associated with a survival benefit and significant attenuation in life-threatening arrhythmias in patients with nonischemic dilated cardiomyopathy...

..The purpose of this study was to investigate the electrophysiologic profile of the pulmonary veins (PVs) and left atrium (LA) in response to autonomic manipulation...

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..Further evaluation of infarct size characterization by cardiac MRI as a predictor of sudden cardiac death is warranted...

..The mechanisms of persistent human atrial fibrillation (AF) are not well understood...

..It is hoped that the results of this study will improve the understanding of myocardial physiology and improve risk stratification and therapy for arrhythmias by uncovering important sex related differences. ..