B-PO04-119 INCIDENCE OF SUDDEN CARDIAC DEATH IN MITRAL VALVE PROLAPSE

Abstract

Mitral valve prolapse (MVP), particularly bileaflet prolapse with mitral annular disjunction, has been associated with an increased risk of sudden cardiac death. The incidence of sudden cardiac death, however, is not known. We aimed to define the incidence of sudden cardiac death in patients with mitral valve prolapse. In this retrospective cohort study, we identified all patients from 2002 to 2017 followed in the UCLA Health System with echocardiographic evidence of MVP or mitral valve leaflet bowing. Patients with other congenital heart diseases, pulmonary disease, cirrhosis, or circulatory shock at time of MVP diagnosis, or history of ventricular arrhythmias prior to MVP were excluded. Up to 5 controls were matched per MVP patient, based on age, Charlson comorbidity index, and presence of echocardiogram ordered within 6 months of qualifying case. Mortality data was obtained from the National Death Index for all patients through 2017. The primary endpoint was ventricular fibrillation, or sudden death from arrhythmic cause. Competing risks analysis was used to compare the incidence of the primary endpoint. We identified 625 patients with mitral valve bowing or prolapse (85 with bowing only, 310 with single leaflet prolapse, 230 with bileaflet prolapse, age 59 ± 17 years, 44.8% male), and 2753 control patients (age 60 ± 18 years, 42.6% male). Median follow-up was 1279 days. The primary endpoint was met in 7 (1.1 %) MVP patients, and 9 (0.33 %) control patients (p = 0.04). The incidence of the primary endpoint in MVP patients was 0.2% per patient year, and 0.09% per patient year in controls. The primary endpoint was met in 1 MVP patient after a mitral valve repair surgery. The incidence of sudden cardiac death in patients with MVP is low but significantly higher than matched controls. Mitral valve repair surgery may not negate the risk of SCD in these patients.