Cardiac resynchronization therapy in patients with permanent atrial fibrillation: results from the Resynchronization for Ambulatory Heart Failure Trial (RAFT).

Background: Cardiac resynchronization (CRT) prolongs survival in patients with systolic heart failure and QRS prolongation. However, most trials excluded patients with permanent atrial fibrillation.

Methods And Results: The Resynchronization for Ambulatory Heart Failure Trial (RAFT) randomized patients to an implantable cardioverter defibrillator (ICD) or ICD+CRT, stratified by the presence of permanent atrial fibrillation.

Use of primary prevention implantable cardioverter-defibrillators in a population-based cohort is associated with a significant survival benefit.

Background: Underuse of implantable defibrillators has been previously noted in patients at risk for sudden cardiac death, as well as for survivors of sudden cardiac death. We sought to determine the utilization rates in a primary prevention implantable cardioverter-defibrillator (ICD)-eligible population and mortality in this group compared with a group that had undergone implantation of this therapy.

Methods And Results: A retrospective cohort of patients from April 1, 2006, to December 31, 2009, was used to define a primary prevention ICD-eligible population.

Predictors of implantable cardioverter-defibrillator use in patients with ischemic cardiomyopathy.

Objectives: The objective of this study was to identify and examine ICD utilization in a large group of eligible coronary artery bypass grafting (CABG) patients with impaired left ventricular function.

Methods: We conducted a retrospective study of ICD eligible patients who had previously undergone CABG surgery between March 1, 1995 and June 30, 2008 at a single tertiary care institution. All patients with a pre-operative left ventricular ejection fraction (LVEF) ≤ 35% were considered ICD eligible.

Differential entrainment distinguishes atrioventricular nodal reentry tachycardia from atrioventricular reentrant tachycardia.

Background: Entrainment from the right ventricular (RV) apex and the base has been used to distinguish atrioventricular reentrant tachycardia (AVRT) from atrioventricular nodal reentry tachycardia (AVNRT). The difference in the entrainment response from the RV apex in comparison with the RV base has not been tested.

Methods: Fifty-nine consecutive patients referred for ablation of supraventricular tachycardia (SVT) were included.

Canadian Registry of ICD Implant Testing procedures (CREDIT): current practice, risks, and costs of intraoperative defibrillation testing.

Background: There is uncertainty about the proper role of defibrillation testing (DT) at the time of implantable cardioverter defibrillator (ICD) insertion.

Methods: A prospective registry was conducted at 13 sites in Canada between January 2006 and October 2007.

Objectives: To document the details of DT, the reasons for not conducting DT, and the costs and complications associated with DT.

A technique for the rapid diagnosis of wide complex tachycardia with 1:1 AV relationship in the electrophysiology laboratory.

Background: The differential diagnosis of wide complex tachycardia (WCT) with 1:1 atrioventricular (AV) relationship is broad. Accurate identification of the tachycardia mechanism is essential for successful ablation. We suggest a simple pacing maneuver that can immediately clarify the tachycardia mechanism in the electrophysiology laboratory.

Mapping and ablation of multiple atrial arrhythmias in a patient with persistent atrial standstill after remote viral myocarditis.

This is a case of multiple atrial arrhythmias (atrioventricular node reentry and two different focal atrial tachycardias) originating from the remaining atrial myocardium after global scarring of both atria following a remote viral myocarditis. All the induced arrhythmias were successfully treated with catheter ablation.

Body-surface potential mapping to aid ablation of scar-related ventricular tachycardia.

We investigated whether body-surface potential mapping (BSPM) during catheter ablation of scar-related ventricular tachycardia (VT) could assist with the identification of VT exit sites. The study population consisted of 9 patients who underwent catheter ablation for VT, among whom 12 induced VTs with known exit sites were identified by entrainment criteria, pace mapping, or site of successful ablation. Paced activation was initiated at various intracardiac sites (20 +/- 4 sites per patient, a total of 180) documented by nonfluoroscopic electroanatomic mapping.