Abstract 16264: Safety and Efficacy Outcomes of Micra Leadless Pacemakers: An Updated Systematic Review and Meta-Analaysis

Background: The Micra leadless pacemaker (LP) is a novel pacing technology that has revolutionized the management of bradyarrhythmias and eliminated the need for intra-cardiac leads. A meta-analysis was performed to assess the long term safety and efficacy outcomes of the LP.

Methods: We included a total of 60 studies. Data was analyzed to calculate outcomes in the pooled proportion of patients undergoing LP implant. Primary efficacy endpoints were successful implantation and acceptable capture threshold of <2V at 1 year. Primary safety outcomes were vascular injury, tamponade, device dislodgement, pneumothorax, and major complications (complications resulting in intervention, prolonged hospital stay, readmission or death).

Results: Successful LP implantation was found to be 99.4% (Cl [99.1%, 99.6%], (P = 0.95)) and acceptable capture threshold of <2V at 1 year was 97.1% (CI [96%, 98.2%], P = 0.001). Major complications occurred in 2.5% (CI [1.3%, 3.6%], P = 0.001). Infection occurred in 0.5% (Cl [0.0%, 0.9%], P = 0.03) and the analysis was homogeneous (I2 = 45.16%, P = 0.04). Vascular injury occurred in 0.9% (CI [0.4%, 1.3%], P = 0.001), cardiac tamponade in 0.4% (CI [0.2%, 0.7%], P = 0.002)) and device dislodgement in 0.3% (CI [0.2%, 0.4%], P < 0.001).

Conclusion: LPs had a high rate of successful implantation and capture threshold at 99.4% and 97.1% respectively, while having low rates of major complications, infections, dislodgement, cardiac tamponade and vascular injury.