Impact of AV conduction disorders on SafeR mode performance.

PURPOSE

CAN-SAVE R is a Canadian multicenter study that compares the effects of a new pacing mode algorithm designed to minimize right ventricular (V) pacing versus DDD mode with a long atrioventricular (AV) delay in a general population of pacemaker (PM) recipients.

STUDY PARTICIPANTS

Patients with permanent atrial fibrillation (AF) or high-degree AV block (AVB) were excluded. We present preliminary data collected in 208 patients (mean age=71 +/- 11 years, 68% men), for the 2-month baseline period during which all PM were programmed in the new pacing mode. The pacing indications were sinus node disease (SND) without AVB in 39%, AVB without SND in 30%, SND and AVB in 16%, and miscellaneous in 15% of patients.

RESULTS

The mean percent V pacing in the overall population was 9.5 +/- 23.8% (range=0-100%, median <1%), ranging between 0.5 +/- 1.5% (median=0) in patients without AVB and 18.7 +/- 31.2% in patients (median = 1) with AVB. Adverse events potentially related to the new pacing mode were observed in two patients with AVB.

CONCLUSIONS

A new pacing mode was effective and safe in a general population of PM recipients without permanent AVB and was associated with an overall <1% median V pacing. CAN-SAVE R will compare the long-term effects of the new pacing mode with DDD with a long AV delay on clinical outcomes and cardiac function.