PO-02-083 LOCATION OF LEADLESS PACEMAKER IMPLANT AND PACING-INDUCED CARDIOMYOPATHY

Abstract

Leadless pacing (LP) is associated with a lower incidence of pacing-induced cardiomyopathy (PICM) compared to transvenous pacing. However, it is unclear if the location of implantation of the LP makes a difference in the incidence of PICM. To compare the incidence of PICM based on the location of implantation of LP 276 patients [Men: 157 (57%), Women: 119 (43%), mean age: 73 ± 11 yrs, all EF > 50%] who received a LP (Micra) between January 2019 – June 2022 formed the study cohort. AV micra and VR micra were implanted in 93 (34%) and 183 (67%) respectively. Fluoroscopically, location of implantation of LP in the Interventricular septum was divided into 3 equal thirds [apical septum (AS), mid septum (MS) and high septum (HS)]. During follow-up, PICM was defined as an left ventricular ejection fraction (EF) drop ≥ 10%. 94/276 (34%), 123/276 (45%), 59/276 (21%) patients had LP implanted at AS, MS and HS locations respectively. During a mean 8 ± 5 months follow-up, 23 patients (8.3%) developed PICM (Men: 9/23 (39%), women: 14/23 (61%) (P = 0.023). Of them, 11/94 (12%), 8/123 (7%) and 4/59 (7%) (P = 0.057) had AS, MS and HS LP implantation. AS location (11/94 (12%) had a higher risk of PICM compared to MS+HS locations [12/182 (7%) (P = 0.044)]. The hazard of PICM was higher with AS location compared to MS+HS locations [Adjusted Hazard ratio: 1.76 (1.13 - 3.25) P = 0.044, (adjusted for age, gender, percentage pacing burden and EF)]. Incidence of PICM with LP is low (8.3%). Women are at higher risk compared to men. AS placement is associated with a higher risk compared to MS and HS placement. Larger randomized studies are needed to confirm our findings.