Enhanced pacemaker algorithm may potentially reduce the risk of adverse clinical outcomes, PREVENT study shows


The study has proven that enhanced atrioventricular search hysteresis algorithm reduces unnecessary right ventricular pacing which correlates with less risk of heart failure hospitalisation, mortality and atrial fibrillation.

PREVENT, a study sponsored by Biotronik, was a prospective, randomised, international, crossover study enrolling 202 patients with a goal to evaluate whether an enhanced atrioventricular search hysteresis with a longer search interval has an increased benefit in terms of ventricular pacing reduction over standard atrioventricular search hysteresis in patients with a class I pacemaker indication.

Biotronik’s enhanced atrioventricular technology, called the Intrinsic Rhythm Support (IRSplus) algorithm, incorporates two different functions: the first is scan hysteresis, which better enables the heart to pace on its own by periodically extending the search time for its natural pacing stimulus (the intrinsic atrioventricular conduction) over six consecutive atrial cycles. The second is the repetitive hysteresis, which recognises when the heart is not pacing on its own (a consistent loss of intrinsic atrioventricular conduction lasting for six consecutive atrial cycles) and switches the mode of the device from extended to basic atrioventricular delay.

Of all patients 47% had a history of intermittent atrioventricular block, which is a sporadic inability of the heart to conduct signals from the atrium into the ventricle. Especially in those patients, the enhanced atrioventricular search hysteresis decreased the median right ventricular pacing to only 21% compared to 26% with standard atrioventricular search hysteresis.

The overall percentage of right ventricular pacing of only 4% (versus 5.5% in patients with standard atrioventricular search hysteresis) represents the potential for further improvement in the reduction of side-effects due to right ventricular pacing.

The study investigators initially state that, “Until now, no other study has evaluated the potential incremental benefit of repetitive hysteresis and scan hysteresis in terms of right ventricular pacing reduction. Our study shows that the additional use of repetitive hysteresis and scan hysteresis on top of the conventional atrioventricular search hysteresis parameters offers further right ventricular pacing reduction.”

“The PREVENT study has proven that the IRSplus enhanced atrioventricular search hysteresis algorithm provides physicians with a straightforward solution for programming Biotronik pacemakers to reduce unnecessary right ventricular pacing-a capability that is so important in minimising the risk of heart failure hospitalisation, mortality, and atrial fibrillation,” commented Marlou Janssen, vice president of Global Marketing and Sales, Biotronik.

Complete results of the study have been published in the article called “Reduction of right ventricular pacing with advanced atrioventricular search hysteresis: results of the PREVENT study”, by Christof Kolb et al, in Pacing and Clinical Electrophysiology (PACE).