Abstract 4366945: Trends in Adverse Events of Leadless Pacemakers in The United States, Between January 2021-December 2024

Leadless pacemakers (LPM) help avoid lead-related complications of transvenous pacemakers (TPM). The FDA first approved LPMs in 2016. However, studies reported more tamponades, thoracotomies, CPR, and deaths in LPM vs TPM recipients. In 2021 the FDA reminded providers of major complications of cardiac perforation during implantation via a warning letter. We assessed adverse event (AE) trends to understand current safety. Methods: Using the FDA’s MAUDE database via Device Events we identified LPM AE reports submitted within 1/1/2021-12/31/2024. Patient problem codes were reviewed for clinical context. Death or serious injury reports were identified with a natural language algorithm. A 10% random sample of death report narratives was evaluated. Estimated implantations were derived from the National Inpatient Sample database and linear regression to calculate the proportion of reports indicating death and serious injury. Outcomes were total AE reports and report category – malfunction, serious injury, or death. Year-to-year trends were analyzed by negative binomial regression (P<0.05). Results: LPM AEs rose from 1,465 (2021) to 3,390 (2024), totaling 9,184 (P < 0.001) while estimated implantations rose from 16,945 (2021) to 24,558 (2024). Death or serious injury reports rose from 714 (7.8%) to 1,385 (15.1%) (P < .001), totaling 4,044 (44.0%). Most deaths (84.1%) were procedure-related. The percentage of reports indicating death or serious injury in annual LPM implantations increased from 8.7% (95% CI, 8.2-9.1) to 13.8% (95% CI, 13.4-14.2 [estimated]) (P = .005). Most common patient problems were no clinical signs, symptoms, or conditions (5,768; 62.8%), pericardial effusion (938; 10.2%), and perforation (914; 10.0%). Perforations included 821 (8.9%) cardiac perforations, declining from 159 (1.7%; 2021) to 130 (1.4%; 2022), then rising to 222 (2.4%; 2023) and 310 (3.4%; 2024) (P < 0.001). Among the 5768 no clinical signs, symptoms, or conditions reports, 19 (0.3%) were deaths and 1,388 (24.1%) serious injuries. Discussion: All types of LPM AE reports rose, however, death and serious injury more than doubled. Discrepancies between report classification as no patient problems and when deaths occurred reflects inaccurate manufacturer coding, representing a quality improvement need. Study limitations included lack of public implantation data and known underreporting to MAUDE. Our findings raise LPM safety concerns and highlight opportunities to improve AE reporting.