A New Dual‐Chamber Pacing Mode to Minimize Ventricular Pacing

Abstract

Despite the low long-term incidence of high-degree atrioventricular (AV) block and the known negative effects of ventricular pacing, programming of the AAI mode in patients with sinus node dysfunction (SND) remains exceptional. A new pacing mode was, therefore, designed to combine the advantages of AAI with the safety of DDD pacing. AAIsafeR behaves like the AAI mode in absence of AV block. First- and second-degree AV blocks are tolerated up to a predetermined, programmable limit, and conversion to DDD takes place in case of high-degree AV block. From DDD, the device may switch back to AAI, provided AV conduction has returned. The safety of AAIsafeR was examined in 43 recipients (70 +/- 12-year old, 24 men) of dual chamber pacemakers implanted for SND or paroxysmal AV block. All patients underwent 24-hour ambulatory electrocardiographic recordings before hospital discharge and at 1 month of follow-up with the AAIsafeR mode activated. No AAIsafeR-related adverse event was observed. At 1 month, the device was functioning in AAIsafeR in 28 patients (65%), and the mean rate of ventricular pacing was 0.2%+/- 0.4%. Appropriate switches to DDD occurred in 15 patients (35%) for frequent, unexpected AV block. AAIsafeR mode was safe and preserved ventricular function during paroxysmal AV block, while maintaining a very low rate of ventricular pacing. The performance of this new pacing mode in the prevention of atrial fibrillation will be examined in a large, controlled study.

Upgrading from right ventricular pacing to biventricular pacing in pacemaker patients with chronic heart failure

“…One of the most attractive options is to avoid unnecessary right ventricular pacing by adequate programming or by using algorithms specifically designed to minimise ventricular pacing in patients who do not require permanent right ventricular pacing 10 11. This option must be evaluated in each patient to avoid unnecessary right ventricular pacing with the risk of development of heart failure.…”

Very Low Ventricular Pacing Rates Can Be Achieved Safely in a Heterogeneous Pacemaker Population and Provide Clinical Benefits: The CANadian Multi‐Centre Randomised Study‐Spontaneous AtrioVEntricular Conduction pReservation (CAN‐SAVE R) Trial

“…The SafeR algorithm (Sorin CRM, Clamart, France) was developed to provide a pacing mode that combines the benefits of AAI with the safety of DDD pacing . The recent randomized SaveR study confirmed the superiority of SafeR in reducing RV pacing when compared to standard DDD pacing in selected patients without high‐degree AV block and in a more general pacemaker population.…”

Pacemaker Timing Cycles and Special Features

“…25 Wenckebach-like and 2:1 pacemaker behavior. A pacemaker is programmed with an atrioventricular interval (AVI) of 125 ms, a post-ventricular atrial refractory period (PVARP) of 225 ms and a maximum tracking rate (MTR) of 400 ms (Wenckebach interval = MTR − AVI + PVARP = 400 − 125 + 225 = 50 ms).…”