Safety and efficacy of leadless pacemaker for cardioinhibitory vasovagal syncope

Background: Single-chamber leadless pacemakers (LPs) have been shown to be an effective alternative to conventional transvenous pacemakers (CTPs), but their benefit in the context of cardioinhibitory vasovagal syncope (CI-VVS) is unknown. Objective: The purpose of this study was to evaluate the safety and efficacy of LP compared with dual-chamber CTP for CI-VVS. Methods: We conducted a multicenter, retrospective study comparing patients who received LP or dual-chamber CTP for drug-refractory CI-VVS. CI-VVS was diagnosed clinically and supported by cardiac monitoring and head-up tilt table testing. The primary efficacy endpoint was freedom from syncope during follow-up. Secondary endpoints included device efficacy and safety estimated by device-related major and minor adverse events (AEs). Results: Seventy-two patients (24 LP, 48 CTP; age 32 ± 5.5 years; 90% female; syncope frequency 7.6 ± 3.4 per year) were included. At 1 year, 91% of patients (22/24) in the LP group and 94% of patients (43/48) in the CTP group met the primary efficacy endpoint (P =.7). Device efficacy endpoint was met in 92% of the LP group and 98% of the CTP group (P =.2). Early major AEs occurred in 2 of 24 in the LP group and 3 of 48 in the CTP group (P =.4). Late major AEs occurred in 0 of 24 in the LP group and 2 of 48 in the CTP group (P = 1). Conclusion: In patients with CI-VVS, single-chamber LP demonstrated equivalent efficacy in reducing syncopal events compared to dual-chamber CTP, with a similar safety profile.