DAVID II Trial Results Shows No Clear Advantages in Pacing Mode


March 13, 2009

March 13, 2009 - Details from the DAVID (Dual Chamber and VVI Implantable Defibrillator) II Trial suggest atrial pacing may be considered a safe alternative to ventricular pacing, but affords no clear advantage over a mode that minimizes pacing.

The results of the study were published this week in the March 10, 2009, issue of the Journal of the American College of Cardiology (JACC).

The original DAVID Trial randomized patients with systolic dysfunction to dual chamber pacing at 70 beats/minute or back-up only pacing. More frequent pacing was associated with worsened outcomes.

Bruce L. Wilkoff, M.D., Cleveland Clinic, and colleagues hypothesized that the mode of pacing chosen for the trial (dual chamber rate-responsive pacing at 70 beats/min) was the culprit and that atrial pacing with native ventricular conduction would be superior to back-up only pacing. The DAVID II trial randomized 600 patients with systolic dysfunction who required an implanted defibrillator to atrial pacing at 70 beats/min versus minimal ventricular pacing at 40 beats/minute. They found there were no significant differences in the combined primary end point of time to death or heart failure hospitalization during follow-up, or in the rates of atrial fibrillation, syncope, and quality of life measures.

For more information: www.acc.org