Safety and Efficacy of Leadless Pacemakers: A Systematic Review and Meta‐Analysis

Abstract

Background Leadless pacemaker is a novel technology, and evidence supporting its use is uncertain. We performed a systematic review and meta‐analysis to examine the safety and efficacy of leadless pacemakers implanted in the right ventricle. Methods and Results We searched PubMed and Embase for studies published before June 6, 2020. The primary safety outcome was major complications, whereas the primary efficacy end point was acceptable pacing capture threshold (≤2 V). Pooled estimates were calculated using the Freedman‐Tukey double arcsine transformation. Of 1281 records screened, we identified 36 observational studies of Nanostim and Micra leadless pacemakers, with most (69.4%) reporting outcomes for the Micra. For Micra, the pooled incidence of complications at 90 days (n=1608) was 0.46% (95% CI, 0.08%–1.05%) and at 1 year (n=3194) was 1.77% (95% CI, 0.76%–3.07%). In 5 studies with up to 1‐year follow‐up, Micra was associated with 51% lower odds of complications compared with transvenous pacemakers (3.30% versus 7.43%; odds ratio [OR], 0.49; 95% CI, 0.34–0.70). At 1 year, 98.96% (95% CI, 97.26%–99.94%) of 1376 patients implanted with Micra had good pacing capture thresholds. For Nanostim, the reported complication incidence ranged from 6.06% to 23.54% at 90 days and 5.33% to 6.67% at 1 year, with 90% to 100% having good pacing capture thresholds at 1 year (pooled result not estimated because of the low number of studies). Conclusions Most studies report outcomes for the Micra, which is associated with a low risk of complications and good electrical performance up to 1‐year after implantation. Further data from randomized controlled trials are needed to support the widespread adoption of these devices in clinical practice.

The knowns and unknowns of leadless pacing in 2022

“…The recent meta-analysis by Ngo et al. reported a capture threshold <2V in 98.9% and 91.5% patients at 1 and 2 year follow up respectively [ 3 ].…”

“…The study is a timely summary of the current published evidence surrounding leadless pacemakers. When considered together with another recent meta-analysis, and two recent reports from the Micra post-approval registry, we can appraise the “knowns” and the “unknowns” of leadless pacing in 2022 [ [3] , [4] , [5] ]. While the origins of the “knowns” and “unknowns” lie beyond medicine, it can provide a useful analytical construct to appraise our current knowledge of leadless pacing or any topic.…”

Leadless pacemaker implantation in a patient with a double-chambered right ventricle

“…The Micra transcatheter pacing system (TPS) is an established bradycardia management, which has eliminated device-related complications (including pocket infection and lead failure) compared with traditional transvenous pacemakers 2–4. Nowadays, the population of adult CHD patients are growing where they are prone to develop conduction disorder requiring device therapy 5.…”

Single-Chamber Leadless Cardiac Pacemaker in Patients Without Atrial Fibrillation: Findings From Campania Leadless Registry

“…Permanent atrial fibrillation (AF) with a slow ventricular rate is the most common indication for single chamber LLPM (2); however, nearly one-third of patients selected to receive this therapy were for indications not associated with AF (3). The outcome of LLPM in the realworld setting was associated with a low risk of complications and good electrical performance up to 1 year after implantation compared to a transvenous pacemaker (4). Actually, there are a few data about the clinical performance of LLPM in patients with pacing indication not associated with AF (3) and no data are still available in a real-world setting.…”