A Leadless Ventricular Pacemaker Providing Atrioventricular Synchronous Pacing in the Real-World Setting: 12-Month Results from the Micra AV Post-Approval Registry.

BACKGROUND

Advances in leadless pacemaker technology have enabled accelerometer-based atrioventricular (AV) synchronous pacing by sensing atrial mechanical contraction.

OBJECTIVES

To report performance of the Micra AV leadless pacemaker from the worldwide Micra AV post-approval registry (PAR) through 12-months.

METHODS

The Micra AV PAR is a prospective single-arm observational registry designed to assess safety and effectiveness of Micra AV in a real-world setting. For the present interim analysis, major complications and system revisions through 12-months were summarized and compared to a historical cohort of 2,667 transvenous dual-chamber pacing patients.

RESULTS

The device was successfully implanted in 796 of 801 patients (99.4%) at 97 centers in 19 countries. Micra AV patients were older (74.1 vs. 71.1 years, P<0.0001) with a higher incidence of renal disease (22.3% vs. 9.8%, P<0.0001) compared to transvenous dual-chamber patients. Through 12-months, the major complication rate was 3.7% in Micra AV patients compared to 8.8% in transvenous dual-chamber patients (hazard ratio [HR]: 0.42, 95% confidence interval [CI]: 0.28-0.61; P<0.001). The system revision rate was 1.5% in Micra AV patients compared to 5.5% for transvenous dual-chamber patients (HR: 0.25, 95% CI: 0.13-0.47; P<0.001); this reduction was largely driven by the absence of lead dislodgements requiring revision. Median AV synchrony index was 79.4% (IQR:65.2%-86.4%) among patients paced >90%.

CONCLUSIONS

The Micra AV leadless pacemaker was implanted with a high rate of success in patients with multiple co-morbidities, with a significantly lower rate of complications and system revisions through 12-months compared to a historical cohort of patients with transvenous dual-chamber pacemakers.