Abstract 16812: Clinical Use of Rate Adaptive Pacing With a Leadless Pacemaker: Results From the Micra Transcatheter Pacing System Post-Approval Registry

Abstract

Introduction: The Micra transcatheter pacemaker has similar functionality and features to existing transvenous VVIR systems despite its small size and intracardiac location. Rate adaptive pacing with Micra is achieved via a programmable 3-axis accelerometer that detects activity in the presence of cardiac motion and has demonstrated to be proportional to workload in the investigational trial. In this analysis, we report the clinical usage of rate adaptive pacing in the Micra Post-Approval Registry (PAR). Methods: The Micra PAR is a prospective, non-randomized, multi-center registry evaluating safety performance of Micra in real-world clinical practice following commercial release. All patients intended to be implanted with a Micra were eligible for enrollment. Micra PAR patients with device data available from an interrogation at least 30-days post-implant were included in this analysis. The clinical usage of VVIR vs. VVI pacing modes was summarized based upon last device interrogation. Results: Among the 713 patients included in this analysis from 117 centers, average age was 75.4 ± 14.4 years and 60.0% were male. Overall 45.3% had rate adaptive pacing enabled. Of 457 patients with a primary pacing indication of bradyarrhythmia with AF, 58.0% were programmed VVIR (figure). The pacing indication distribution for the VVIR patient group was: 82% bradycardia with AF, 4% sinus node dysfunction, 8% AV block, 4% syncope, and 1% other. Among patients with a primary indication of syncope or sinus node dysfunction, the majority were programmed VVI (83.9% and 79.1%, respectively). Of patients with <10% pacing, 2.5% were programmed VVIR vs. 97.5% VVI. Of those with >90% pacing, 88.8% were VVIR vs. 11.2% VVI. Conclusions: In real-world clinical practice, VVIR was programmed in <50% of Micra patients. Patient groups with the highest utilization of VVIR mode include those with >90% ventricular pacing and those with a primary pacing indication of bradyarrhythmia with AF.