Rationale and Design of the Comparative Effectiveness of ICD Versus Non-ICD Therapy in Contemporary Heart Failure Patients at a Low Risk for Arrhythmic Death (CONTEMP-ICD) trial.

Background: Current recommendations for a prophylactic (primary prevention) implantable cardioverter defibrillator (ICD) in patients with both ischemic and non-ischemic heart failure with reduced ejection fraction (HFrEF) originate from clinical trials conducted in selected patients over 20 years ago that showed an overall statistically significant survival benefit associated with a primary prevention ICD in the range of 23%-34%. The recent introduction of angiotensin receptor-neprilysin inhibitors [ARNI] and sodium glucose co-transporter 2 inhibitors [SGLT2i]) was shown to further reduce the risk of sudden cardiac death (SCD) in patients with HFrEF. Thus, there is an unmet need appropriately designed comparative effectiveness clinical trials aimed to reassess the survival benefit of a primary prevention ICD in contemporary patients with HFrEF.

A novel measure of AV-conduction predicts clinical outcomes and benefit from CRT-D in non-LBBB patients with wide QRS and a low left ventricular ejection fraction.

Background: PR-interval reflects atrioventricular timing but does not well characterize adverse hemodynamics. Novel ECG parameters of conduction may identify benefit from non-dyssynchronous ventricular pacing to correct long atrioventricular conduction delays.

Objective: Evaluating novel ECG parameters to identify risk of heart failure (HF)/death and benefit vs harm by CRT-D in MADIT-CRT non-LBBB patients.

Identifying Demographic Factors Affecting the ECG Duration Collected Using a Single-Lead ECG Patch Device.

Introduction: Atrial fibrillation (AF), affecting 3% of the US adults, is the most common arrhythmia. While ambulatory electrocardiogram (ECG) monitoring is essential for AF detection, conventional technologies have diagnostic limitations due to AF's sporadic nature. ECG patches offer extended monitoring periods, though their effectiveness is primarily limited by deteriorating skin-electrode contact rather than battery or memory constraints.

Asthma and the risk of cardiac events among patients with long QT syndrome after age 40.

Background: Limited data exist on the impact of asthma on long QT syndrome (LQTS) in middle-aged and older adults.

Objective: This study aimed to examine the association between asthma, β2-agonist treatment, and cardiac events (CEs) in LQTS patients over 40 years of age.

Methods: The risk of CEs (comprising syncope, aborted cardiac arrest, implantable cardioverter-defibrillator shock, or sudden cardiac death) from age 40 through 75 years, by the presence of asthma with and without treatment with a β2-agonist inhaler, was assessed among 1020 LQTS patients from the Rochester LQTS Registry.

Predicting Ventricular Tachyarrhythmias in Patients With Left Ventricular Ejection Fraction Improvement Following Cardiac Resynchronization Therapy.

Background: Patients undergoing cardiac resynchronization therapy with a defibrillator (CRT-D) often experience improvements in the left ventricular ejection fraction (LVEF). This study aimed to identify predictors of ventricular tachyarrhythmias (VTA) in patients with CRT-D devices and LVEF improvement beyond guideline recommendations for a defibrillator.

Methods: Patients randomized to the CRT-D arm of the Multicenter Automatic Defibrillator Implantation Trial With Cardiac Resynchronization Therapy trial who improved their LVEF to > 35% at 12 months following CRT-D implant were included in this analysis (N = 651).

Reassessing the need for primary prevention implantable cardioverter-defibrillators in contemporary patients with heart failure.

The main function of the implantable cardioverter-defibrillator (ICD) is to protect against sudden cardiac death (SCD) due to ventricular tachyarrhythmia (VTA). Current guidelines provide a recommendation to implant a prophylactic ICD for the primary prevention of SCD in individuals having heart failure with reduced ejection fraction (HFrEF) who never experienced a previous sustained VTA. However, these recommendations are based on clinical trials conducted more than 20 years ago and may not be applicable to contemporary patients with HFrEF who have a lower arrhythmic risk as a result of advances in heart failure medical therapies.

Reassessing the need for primary prevention implantable cardioverter-defibrillators in contemporary patients with heart failure.

The main function of the implantable cardioverter-defibrillator (ICD) is to protect against sudden cardiac death (SCD) due to ventricular tachyarrhythmia (VTA). Current guidelines provide a recommendation to implant a prophylactic ICD for the primary prevention of SCD in individuals having heart failure with reduced ejection fraction (HFrEF) who never experienced a previous sustained VTA. However, these recommendations are based on clinical trials conducted more than 20 years ago and may not be applicable to contemporary patients with HFrEF who have a lower arrhythmic risk as a result of advances in heart failure medical therapies.

Sudden Unexpected Death in Patients With Implanted Cardiac Defibrillators: Results of Postmortem Interrogation in MADIT-CRT.

Background: Ventricular tachyarrhythmia presumably causes sudden unexpected death (SUD) in patients lacking an implantable cardioverter-defibrillator (ICD). The mechanism of SUD is less clear in patients with an ICD to remedy ventricular tachycardia (VT) or ventricular fibrillation (VF).

Objectives: This study sought to assess mechanisms of SUD in patients with an ICD.

Utilization of an undergraduate emergency department research associate program for the screening and recruitment of research subjects with heart failure into a clinical study.

Background: Enrolling heart failure (HF) patients in clinical studies is challenging. Emergency department (ED) may use students as research associates programs, such as the University of Rochester Medical Center (URMC) ED Research Associate (EDRA) program, to screen and consent patients for clinical studies. This manuscript examines the effectiveness of the URMC EDRA program in consenting HF patients into a clinical study.

Risk of recurrent ventricular tachyarrhythmia following the occurrence of a first ventricular arrhythmic event in patients with a primary prevention implantable cardioverter-defibrillator.

Background: There are limited data on clinical and arrhythmic outcomes after a first ventricular tachyarrhythmia (VTA) in heart failure (HF) patients who receive a primary prevention implantable cardioverter-defibrillator (ICD).

Objective: This study was designed to quantify the burden of and to identify risk factors for recurrent VTA in this population and to evaluate the risk of all-cause mortality associated with recurrent VTA.

Methods: The study comprised 789 patients who experienced VTA following primary prevention ICD implantation in 5 ICD trials (MADIT-II, MADIT-RISK, MADIT-CRT, MADIT-RIT, RAID).

Risk stratification for ventricular tachyarrhythmia in patients with nonischemic cardiomyopathy.

Introduction: The implantable cardioverter defibrillator reduces mortality among patients with heart failure (HF) due to ischemic heart disease. Clinical trial data have called into question the benefit of an ICD in patients with HF due to nonischemic cardiomyopathy (NICM). We developed a risk stratification score for ventricular tachyarrhythmia (VTA) among patients with NICM receiving a primary prevention ICD.

Coronary artery disease and the risk of life-threatening cardiac events after age 40 in long QT syndrome.

Background And Aims: Long QT syndrome (LQTS) and coronary artery disease (CAD) are both associated with increased risk of ventricular tachyarrhythmia However, there are limited data on the incremental risk conferred by CAD in adult patients with congenital LQTS. We aimed to investigate the risk associated with CAD and life threatening events (LTEs) in patients with LQTS after age 40 years.

Methods: The risk of LTEs (comprising aborted cardiac arrest, sudden cardiac death, or appropriate defibrillator shock) from age 40 through 75 years was examined in 1,020 subjects from the Rochester LQTS registry, categorized to CAD ( = 137) or no-CAD ( = 883) subgroups.

Emotional Awareness Is Correlated With Ambulatory Heart Rate Variability: A Replication and Extension.

Objective: In healthy volunteers, a positive association has previously been observed between emotional awareness (EA), the ability to identify and describe emotional experiences in oneself and others, and resting heart rate variability (HRV), which is dominated by vagus nerve activity. The current study aimed to investigate the EA-HRV association across multiple assessments in a "real-world" ambulatory context in patients with long QT syndrome (LQTS) who are at genetic risk for sudden cardiac death.

Methods: Participants (157 LQTS patients; Mean Age = 35.

Risk Prediction in Male Adolescents With Congenital Long QT Syndrome: Implications for Sex-Specific Risk Stratification in Potassium Channel-Mediated Long QT Syndrome.

Background: Sex-specific risk management may improve outcomes in congenital long QT syndrome (LQTS). We recently developed a prediction score for cardiac events (CEs) and life-threatening events (LTEs) in postadolescent women with LQTS. In the present study, we aimed to develop personalized risk estimates for the burden of CEs and LTEs in male adolescents with potassium channel-mediated LQTS.

Utility of Left and Right Ventricular Strain in Arrhythmogenic Right Ventricular Cardiomyopathy: A Prospective Multicenter Registry.

Background: Imaging evaluation of arrhythmogenic right ventricular cardiomyopathy (ARVC) remains challenging. Myocardial strain assessment by echocardiography is an increasingly utilized technique for detecting subclinical left ventricular (LV) and right ventricular (RV) dysfunction. We aimed to evaluate the diagnostic and prognostic utility of LV and RV strain in ARVC.

The Influence of Hybrid Comprehensive Telerehabilitation on Anxiety in Heart Failure Patients: The TELEREH-HF Randomized Clinical Trial.

Telerehabilitation for heart failure (HF) patients is beneficial for physical functioning, prognosis, and psychological status. The study aimed at evaluating the influence of hybrid comprehensive telerehabilitation (HCTR) on the level of anxiety in comparison to usual care (UC). The TELEREH-HF study was a multicenter prospective RCT in 850 clinically stable HF participants.

QRS Morphology and the Risk of Ventricular Tachyarrhythmia in Cardiac Resynchronization Therapy Recipients.

Background: There are conflicting data on the effect of cardiac resynchronization therapy with a defibrillator (CRT-D) on the risk of life-threatening ventricular tachyarrhythmia in heart failure patients.

Objectives: The authors aimed to assess whether QRS morphology is associated with risk of ventricular arrhythmias in CRT recipients.

Methods: The study population comprised 2,862 patients implanted with implantable cardioverter defibrillator (ICD)/CRT-D for primary prevention who were enrolled in 5 landmark primary prevention ICD trials (MADIT-II [Multicenter Automated Defibrillator Implantation Trial], MADIT-CRT [Multicenter Automated Defibrillator Implantation Trial-Cardiac Resynchronization Therapy], MADIT-RIT [Multicenter Automated Defibrillator Implantation Trial-Reduction in Inappropriate Therapy], MADIT-RISK [Multicenter Automated Defibrillator Implantation Trial-RISK], and RAID [Ranolazine in High-Risk Patients With Implanted Cardioverter Defibrillators]).

Genetic QT Score and Sleep Apnea as Predictors of Sudden Cardiac Death in the UK Biobank.

Introduction: The goal of this study was to evaluate the association between a polygenic risk score (PRS) for QT prolongation (QTc-PRS), QTc intervals and mortality in patients enrolled in the UK Biobank with and without sleep apnea.

Methods: The QTc-PRS was calculated using allele copy number and previously reported effect estimates for each single nuclear polymorphism SNP. Competing-risk regression models adjusting for age, sex, BMI, QT prolonging medication, race, and comorbid cardiovascular conditions were used for sudden cardiac death (SCD) analyses.