Real-world long-term battery longevity of leadless pacemakers. (3rd October 2022)

• Record Type: Journal Article
• Authors: Breeman, K T N; Dijkshoorn, L A; Beurskens, N E G; Wilde, A A M; Tjong, F V Y; Knops, R E
• Is Part Of: European heart journal. Volume 43(2022)Supplement 2
• Publication Date: 2022-10-03
• Subjects: Cardiology -- Periodicals; Heart -- Diseases -- Periodicals; 616.12005
• DOI: 10.1093/eurheartj/ehac544.486
• Languages: English
• ISSNs: 0195-668X

Abstract

Abstract: Background: Leadless pacemakers (LPs) have proven safe on the mid-term. Long-term safety will largely depend on the need for replacements with a concomitant risk of complications. As replacements are mainly due to battery depletion, battery longevity is, in essence, an important determinant of long-term safety. Mean battery longevity of the most often implanted LP (Micra VR) predicted by the manufacturer is 12 years, but mid- and long-term data is lacking. Purpose: We sought to determine the long-term battery longevity of this LP in a real-world cohort. Methods: Consecutive patients with an LP implantation at our tertiary hospital from January 2014 to September 2021 were included in a prospective cohort. Baseline characteristics and electrical parameters during all yearly follow-up visits were assessed. Results: 105 patients (73 [70%] male, age at implantation 80±9 years) were included. Pacing indications were atrial fibrillation with slow conduction (34 [32%]), third degree AV block (35 [33%]), incomplete AV block (12 [11%]), sinus node disease (23 [22%]) and unexplained syncope (1 [1%]). At implantation, pacing threshold, impedance and R-wave amplitude were 0.76±0.64V at 0.24ms, 790±220Ω and 11.1±4.9mV, respectively, lower rate was programmed at 50–60/min in 88 (84%), <50/min in 8 (7.6%) and >60/min in 9 (8.6%) and rate-responsive pacing was programmed on in 51 (49%). Median follow-up was 25 months (range 2–88 months). Pacing percentage was 46% (IQR 12–98%) at year 0; 64% (10–99%) at year 5 and 91% (56–100%) at year 7. No battery failures were seen during follow-up. At 3 years, expected battery longevity was >8 years (maximum value) in nearly all patients (49/50 [98%]) and at 5 years in the majority (16/18 [89%]) of patients; at 7 years, expected battery longevity ranged from 4.1 to >8 years (Figure). This implies an expected battery longevity of >13 years in the majority of patients. In two subjects, expected battery longevity was below the maximum value within 5 years after implantation. In the first, latest follow-up visit was after 3 years and expected battery longevity was 3.0 years. An increase in pacing percentage of +70 percent points was seen during follow-up and there was a relatively high pacing capture threshold (1.5V@0.4ms). In the second, the latest follow-up visit was at 6 years, and expected battery longevity was 1.9 years. This was caused by a large increase in pacing percentage (+80 percentage points) and lower rate of 70/min; pacing threshold was 0.5V@0.24ms. We did not see clear overall differences in expected battery longevity at 5 years, when the patients were stratified per quartile pacing percentage. Of 34 deaths during follow-up, 31 (91%) had expected battery longevity >8 years at the last follow-up visit. Conclusions: These long-term real-world data suggest that the battery longevity of the Micra LP will exceed the expected battery longevity. Data from larger registries is necessary to confirm these results. Funding Acknowledgement: Type of funding sources: None.