Anatomical location of leadless pacemaker and the risk of pacing‐induced cardiomyopathy

Abstract

AbstractBackgroundIt is unclear if the location of implantation of the leadless pacemaker (LP) makes a difference in the incidence of pacing‐induced cardiomyopathy (PICM).AimThe aim of this study was to compare the incidence of PICM based on the location of implantation of LP.MethodsA total of 358 consecutive patients [women: 171 (48%), mean age: 73 ± 15 years] with left ventricular ejection fraction (EF) > 50%, who received an LP (Micra) between January 2017 and June 2022, formed the study cohort. Micra‐AV and Micra‐VR were implanted in 122 (34%) and 236 (66%) patients, respectively. Fluoroscopically, the location of implantation of LP in the interventricular septum (IS) was divided into two equal halves (apex/apical septum [AS] and mid/high septum [HS]). During follow‐up, PICM was defined as an EF drop of ≥10%.ResultsLP was implanted in 109 (34%) and 249 (66%) patients at AS and HS locations, respectively. During a mean 18 ± 8 months follow‐up, 28 patients (7.8%) developed PICM. Among the 249 patients with HS placement of LP, 10 (4%) developed PICM, whereas among the 109 patients with AS placement of LP, 18 (16.5%) developed PICM (p = .002). AS location was associated with a higher risk of PICM compared to HS locations (adjusted hazard ratio: 4.42, p < .001).ConclusionAS location of LP was associated with a higher risk of PICM compared to HS placement. Larger randomized studies are needed to confirm our findings.