Abhishek Bose

Impact of myocardial viability and left ventricular lead location on clinical outcome in cardiac resynchronization therapy recipients with ischemic cardiomyopathy.

Cardiac resynchronization therapy (CRT) recipients with ischemic cardiomyopathy (ICM) have scar segments that may limit ventricular resynchronization and clinical response. The impact of myocardial viability at the left ventricular (LV) pacing site on CRT response is poorly elucidated.

Prognostic implication of baseline PR interval in cardiac resynchronization therapy recipients

BACKGROUND Prolongation of the baseline ECG PR interval is frequently encountered among cardiac resynchronization therapy (CRT) recipients. There are conflicting data regarding the association of a prolonged PR interval with long-term clinical outcome in this patient group. OBJECTIVE The purpose of this study was to compare clinical outcomes and response to CRT in patients with normal (<200 ms) vs prolonged (≥200 ms) baseline PR interval. METHODS In this study, 283 patients (normal PR interval: n = 158; prolonged PR interval: n = 125) with documented baseline intrinsic PR interval were followed for 3 years after CRT implantation. The study population consisted of 24.7% women (mean age 66 ± 13 years, left ventricular ejection fraction 24% ± 7%). RESULTS A Cox proportional hazard model identified baseline PR interval as a predictor of the composite end-point (all-cause mortality, heart failure hospitalization, left ventricular assist device implantation, and heart transplantation) in univariate analysis (hazard ratio [HR] 1.49, 95% confidence interval [CI] 1.02-2.17, P = .04) but not in multivariate analysis. It also predicted heart failure hospitalization in univariate (HR 1.6, 95% CI 1.1-2.4, P = .02) and multivariate analysis (HR 1.6, 95% CI 1.0-2.3, P = .03). A prolonged PR interval was associated with lower probability of reverse remodeling defined as ≥10% improvement in ejection fraction (64% vs 77%, P = .057), especially in patients with non-left bundle branch block ECG morphology (41% vs 68%, P = .03). CONCLUSION Among patients with CRT, a prolonged baseline PR interval is an independent predictor of worse prognosis and lower probability of reverse remodeling, especially for patients with non-left bundle branch block morphology on ECG.

Electrical delay in apically positioned left ventricular leads and clinical outcome after cardiac resynchronization therapy.

Electrical Delay in Apically Positioned LV Leads. Introduction: In recent studies, an anatomical apical left ventricular (LV) lead pacing location has been associated with deleterious outcome after cardiac resynchronization therapy (CRT). The differential impact of the LV lead electrical location in these patients remains unknown.

Biomarkers in electrophysiology: role in arrhythmias and resynchronization therapy.

Circulating biomarkers related to inflammation, neurohormones, myocardial stress, and necrosis have been associated with commonly encountered arrhythmic disorders such as atrial fibrillation (AF) and more malignant processes including ventricular arrhythmias (VA) and sudden cardiac death (SCD). Both direct and indirect biomarkers implicated in the heart failure cascade have potential prognostic value in patients undergoing cardiac resynchronization therapy (CRT). This review will focus on the role of biomarkers in AF, history of SCD, and CRT with an emphasis to improve clinical risk assessment for arrhythmias and patient selection for device therapy. Notably, information obtained from biomarkers may supplement traditional diagnostic and imaging techniques, thus providing an additional benefit in the management of patients.

Does Prior Valve Surgery Change Outcome in Patients Treated with Cardiac Resynchronization Therapy

Cardiac valve surgery (CVS) has been implicated as a potential barrier to optimal response after cardiac resynchronization therapy (CRT) though prospective data regarding outcome remains limited. We sought to determine CRT response in patients with a prior history of CVS.

ANGIOGRAPHIC AND NUCLEAR IMAGING PREDICTORS OF RESPONSE TO CARDIAC RESYNCHRONIZATION THERAPY (CRT) IN ISCHEMIC CARDIOMYOPATHY

Although scar has been associated with poor outcome after CRT, the impact of coronary artery disease (CAD) severity or ischemia on CRT response remains uncertain. A prospective cohort of CRT patients with ischemic cardiomyopathy was evaluated for ischemia and scar with nuclear perfusion imaging.