Antitachycardia Pacing Efficacy Significantly Improves With Cardiac Resynchronization Therapy

Introduction and objectives. The effect of cardiac resynchronization therapy on antitachycardia pacing still has to be determined. Patients and method. A total of 490 heart failure patients with an indication for an implantable cardioverter-defibrillator participated in the VENTAK CHF/CONTAK CD study, a single-blind, randomized, placebo-controlled study. We compared antitachycardia pacing efficacy in patients with or without cardiac resynchronization therapy. Due to the device design, antitachycardia pacing was always given simultaneously via both left and right leads (i.e., biventricular antitachycardia pacing). Patients were randomized at the time of implantation, with the pacing mode being programmed accordingly one month later. Results. During follow-up, 32 patients received antitachycardia pacing: 15 with cardiac resynchronization therapy and 17 without. In the 15 patients receiving resynchronization, 221 episodes of tachycardia were treated by antitachycardia pacing. The sinus rhythm conversion rate was 90.5%. In patients not receiving resynchronization, there were 139 episodes of tachycardia and the sinus rhythm conversion rate was 69.1%. The sinus rhythm conversion rate in the cardiac resynchronization therapy group was significantly higher than that in the control group (P<.0001). Moreover, antitachycardia pacing efficacy improved with time in the whole study population. Conclusions. The efficacy of biventricular antitachycardia pacing in heart failure patients is significantly better in those with cardiac resynchronization therapy than in those without.