Catheter ablation of atrial fibrillation in patients with cor triatriatum sinister; case series and review of literature.

Introduction: Cor triatriatum sinister (CTS) is a rare congenital heart defect characterized by fibromuscular septation of the left atrium associated with atrial fibrillation (AF). The incidence of hemodynamically insignificant CTS in the AF ablation population and effect on ablation success are not known. Furthermore, little is known about the potential effect of CTS on arrhythmogenic substrate.

Electrical delays in quadripolar leads with cardiac resynchronization therapy.

Background: Pacing at sites of late intraventricular activation (QLV) or long interventricular conduction (right ventricle [RV]-left ventricular [LV]) have been associated with improved cardiac resynchronization therapy (CRT) outcomes. Quadripolar leads improve CRT outcomes by allowing for electrical repositioning to optimize pacing sites. However, little is known regarding the effect of such repositioning on electrical delay.

The effect of posture, exercise, and atrial pacing on atrioventricular conduction in systolic heart failure.

Background: Optimization of atrioventricular (AV) intervals for cardiac resynchronization therapy (CRT) programming is typically performed in supine patients at rest, which may not reflect AV timing in other conditions.

Objective: To evaluate the effects of posture, exercise, and atrial pacing on intrinsic AV intervals in patients with CRT devices.

Methods: Rate-dependent A-V delay by exercise was a multicenter, prospective trial of patients in sinus rhythm following CRT implantation.

Biventricular pacemaker/defibrillators versus biventricular pacemakers in patients with non-ischemic cardiomyopathy.

The decision to employ defibrillator therapy in patients with non-ischemic cardiomyopathy is driven by reduction in mortality. The strength of data supporting this therapy has led to its incorporation in medical guidelines and general practice across the world. Cardiac resynchronization therapy has also been proven to reduce heart failure hospitalization and improve quality of life.

Acute hemodynamic effects of atrial pacing with cardiac resynchronization therapy.

Background: Chronotropic incompetence is common among patients with advanced heart failure (HF), thus atrial pacing (AP) is frequently utilized in this population. The hemodynamic effects of AP during cardiac resynchronization therapy (CRT) have not been well studied.

Objective: The purpose of this study was to compare the acute hemodynamic response during CRT of AP with that during atrial sensing (AS).