Efficacy and safety of implantable cardioverter-defibrillator implantation in the elderly-The I-70 Study: A randomized clinical trial.

Background: There is conflicting evidence on the efficacy of primary prevention implantable cardioverter-defibrillator (ICD) implantation in the elderly.

Objective: The purpose of this study was to determine the efficacy and safety of ICD implantation in patients 70 years and older.

Methods: Patients (n = 167) aged 70 years or older and eligible for ICD implantation were randomly assigned (1:1) to receive either optimal medical therapy (OMT) (n = 85) or OMT plus ICD (n = 82).

Antiarrhythmic effects of metformin.

Atrial fibrillation/flutter (AF) is a major public health problem and is associated with stroke, heart failure, dementia, and death. It is estimated that 20%-30% of Americans will develop AF at some point in their life. Current medications to prevent AF have limited efficacy and significant adverse effects.

Ankle-Brachial Index and Risk of Sudden Cardiac Death in the Community: The ARIC Study.

Background: Sudden cardiac death (SCD) is a significant global public health problem accounting for 15% to 20% of all deaths. A great majority of SCD is associated with coronary heart disease, which may first be detected at autopsy. The ankle-brachial index (ABI) is a simple, noninvasive measure of subclinical atherosclerosis.

Temporary-permanent pacemakers are associated with better clinical and safety outcomes compared to balloon-tipped temporary pacemakers.

Background: Balloon Tipped Temporary Pacemakers (BTTP) are the most used temporary pacemakers; however, they are associated with a risk of dislodgement and thromboembolism. Recently, Temporary Permanent Pacemakers (TPPM) have been increasingly used. Evidence of outcomes with TPPM compared to BTTP remains scarce.

QT prolongation predicts all-cause mortality above and beyond a validated risk score.

Introduction: QT prolongation is a risk factor for life-threatening arrhythmias and sudden cardiac death. In large cohorts, QT interval was associated with all-cause mortality, but these analyses may contain residual confounding. Whether the QT interval provides prognostic information above and beyond a validated mortality risk score is unknown.

Cardiovascular disease burden in the Middle East and North Africa region.

Introduction: Cardiovascular disease (CVD) remains the leading cause of death globally, including the Middle East and North Africa (MENA) region. However, limited research has been conducted on the burden of CVD in this region. Our study aims to investigate the burden of CVD and related risk factors in the MENA.

Cardiovascular Autonomic Function and Incident Chronic Obstructive Pulmonary Disease Hospitalizations in Atherosclerosis Risk in Communities.

The autonomic nervous system extensively innervates the lungs, but its role in chronic obstructive pulmonary disease (COPD) outcomes has not been well studied. We assessed relationships between cardiovascular autonomic nervous system measures (heart rate variability [HRV] and orthostatic hypotension [OH]) and incident COPD hospitalization in the multicenter ARIC (Atherosclerosis Risk In Communities) study. We used Cox proportional hazards regression models to estimate hazard ratios and 95% confidence intervals between baseline (1987-1989) autonomic function measures (HRV measures from 2-minute electrocardiograms and OH variables) and incident COPD hospitalizations through 2019.

Mortality associated with antiarrhythmic medication for atrial fibrillation among patients with left ventricular hypertrophy.

Background: Atrial fibrillation (AF) guidelines recommend amiodarone as the preferred antiarrhythmic medication (AAM) in patients with left ventricular hypertrophy (LVH), due to potential pro-arrhythmic risk with other AAM. However, there are limited data to support this assertion.

Methods: We retrospectively analyzed the records of 8204 patients who were prescribed AAM for AF and had transthoracic echocardiogram (TTE) at the multicenter, VA Midwest Health Care Network from 2000 to 2021.

Perioperative changes in left ventricular systolic function following surgical revascularization.

Background: Nearly 1/3rd of patients undergoing coronary artery bypass graft surgery (CABG) have left ventricular systolic dysfunction. However, the extent, direction and implications of perioperative changes in left ventricular ejection fraction (LVEF) have not been well characterized in these patients.

Methods: We studied the changes in LVEF among 549 patients with left ventricular systolic dysfunction (LVEF <50%) who underwent CABG as part of the Surgical Treatment for Ischemic Heart Failure (STICH) trial.

Mortality and readmission risk in relation to QRS duration among patients hospitalized for heart failure with preserved ejection fraction.

Background: In ambulatory patients with heart failure (HF) with preserved ejection fraction (HFpEF), QRS prolongation (QRS > 120 msec) and left bundle branch block (LBBB) each carry an increased risk of cardiovascular mortality and/or HF hospitalization. Less is known about implications of conduction abnormalities following an acute HF hospitalization for HFpEF.

Methods And Results: A retrospective cohort of 1454 patients discharged from after a HF hospitalization between 2015 and 2019 with ejection fraction (EF) ≥ 45% were identified (age 75.

Heart Rate Variability on 10-Second Electrocardiogram and Risk of Acute Exacerbation of COPD: A Secondary Analysis of the BLOCK COPD Trial.

Introduction: Autonomic dysfunction is common in chronic obstructive pulmonary disease (COPD), and worse autonomic function may be a marker of risk for acute exacerbations of COPD (AECOPD). Heart rate variability (HRV) is a measure of autonomic function. Our objective was to test whether lower (worse) HRV is a risk factor for AECOPD.

Improvement of left ventricular function with surgical revascularization in patients eligible for implantable cardioverter-defibrillator.

Introduction: Left ventricular ejection fraction (EF) ≤ 35% is the cornerstone criterion for implantable cardioverter-defibrillator (ICD) eligibility. Improvement in EF may occur in ICD-eligible patients after coronary artery bypass graft surgery (CABG). However, the incidence, predictors, and outcomes of this process are unclear.

Predictors of Sudden Cardiac Arrest Among Patients With Post-Myocardial Infarction Ejection Fraction Greater Than 35.

Background Sudden cardiac arrest (SCA) risk increases after myocardial infarction (MI) in patients with a reduced ejection fraction (EF). However, the risk factors for SCA among patients with a post-MI EF >35% remain poorly understood. Methods and Results Using the Optum de-identified electronic health record data set from 2008 to 2017, we identified patients with an incident MI diagnosis and troponin elevation who had a post-MI EF >35% and underwent coronary angiography.

Implantable Cardioverter-Defibrillator Shocks During COVID-19 Outbreak.

Background COVID-19 was temporally associated with an increase in out-of-hospital cardiac arrests, but the underlying mechanisms are unclear. We sought to determine if patients with implantable defibrillators residing in areas with high COVID-19 activity experienced an increase in defibrillator shocks during the COVID-19 outbreak. Methods and Results Using the Medtronic (Mounds View, MN) Carelink database from 2019 and 2020, we retrospectively determined the incidence of implantable defibrillator shock episodes among patients residing in New York City, New Orleans, LA, and Boston, MA.

Chronotropic Index and Acute Exacerbations of Chronic Obstructive Pulmonary Disease: A Secondary Analysis of BLOCK COPD.

The chronotropic index quantifies the proportion of the expected heart rate increase that is attained during exercise. The relationship between the chronotropic index and acute exacerbations of chronic obstructive pulmonary disease (AECOPDs) has not been evaluated. To determine whether a higher chronotropic index during a 6-minute walk (CI-6MW) is associated with lower risk of AECOPD and whether the CI-6MW is a marker of susceptibility to adverse effects of metoprolol in chronic obstructive pulmonary disease (COPD).

Trajectory of left ventricular ejection fraction among individuals eligible for implantable cardioverter-defibrillator.

Objective: Examine the trajectory of left ventricular ejection fraction (EF) among patients eligible for implantable cardioverter-defibrillator (ICD) therapy.

Background: EF is the cornerstone criterion for ICD therapy, but the risk of sudden cardiac death remains after an improvement in EF.

Methods: We examined the trajectory of EF among 1178 participants of the Sudden Cardiac Death in Heart Failure Trial (SCD-HeFT) who had three or more assessments of EF, at least 90 days apart.