P1665
Chronic apical and non-apical right ventricular pacing in patients with high-grade atrioventricular block: results of the right pace study

Extract

Background/Introduction: Chronic right ventricular apical (RVA) pacing is associated with an increased risk of atrial fibrillation, morbidity and even mortality. Non-RVA pacing may yield a more physiologic ventricular activation and provide potential long-term benefits. Non-RVA pacing has recently been adopted as standard procedure at many implanting centers.

Purpose: The aim of the study was to compare the two approaches to chronic RV pacing currently adopted in clinical practice: RVA and non-RVA pacing.

Methods: The Right Pace study was a multi-center, prospective, single-blind, nonrandomized trial. 437 patients indicated for dual-chamber pacemaker implantation with high percentage of RV pacing were included. RV lead tip target location was the apex or the inter-ventricular septum.

Results: The RVA (247 patients) and Non-RVA group (163 patients) did not differ in baseline characteristics. During a median follow-up of 19 months (25th to 75th percentiles, 13–25), 17 patients died. The rates of the primary outcome of death for any cause or hospitalization for heart failure were comparable between groups (log-rank test, p=0.609), as well as the rates of the composite of death for any cause, hospitalization for heart failure, or an increase in the left ventricular end-systolic volume of 15% or more as compared with the baseline evaluation (secondary outcome, p=0.703). After X-rays central adjudication, the comparison between Adjudicated RVA (239 patients) and Adjudicated non-RVA (170 patients) confirmed the lack of difference in the rates of primary (p=0.402) and secondary outcome (p=0.941). The pacing site, according to local or core laboratory assignment, did not show association with outcomes at multivariate analysis. Only the baseline ejection fraction turned out to be an independent determinant of the primary outcome (HR: 0.94, CI: 0.90 to 0.,98; p=0.002).