Abstract 14684: Ambulatory Electrocardiogram for Mortality Risk Stratification in Arrhythmic Mitral Valve Prolapse

Abstract

Introduction: Mitral valve prolapse (MVP) has been associated with sudden death. There is little data on whether ambulatory ECG monitoring can be used to better define risk. Hypothesis: Severity of ventricular arrhythmia (VA) on ambulatory ECG is associated with mortality in MVP patients. Methods: We studied patients aged 18 - 90 years with MVP on echocardiography between 2016-19 at our institution who underwent ambulatory ECG monitoring. Ambulatory ECGs were reviewed for PVC burden and rate of non-sustained ventricular tachycardia (NSVT). VA severity was classified as none (PVC<1% and no NSVT), mild (PVC>1% or NSVT<120 beats per minute [bpm]), moderate (NSVT 120-179 bpm) and severe (NSVT≥180 bpm). Kaplan-Meier survival analysis was used to assess whether VA severity is associated with mortality. Results: Holter monitoring was performed in 188 (29.5%) of 637 MVP patients. None, mild, moderate and severe VA was present in 91 (48.4%), 27 (14.4%), 56 (29.8%) and 14 (7.5%), respectively. On multivariate analysis of clinical and echocardiographic features, only bileaflet prolapse was associated with moderate to severe VA (odds ratio [95% CI], 2.10 [1.05-4.16, p=0.03). After a median (IQR) follow-up of 33 (19-46) months, 8 (4.2%) died. VA severity was positively associated with mortality (p=0.0189). Conclusions: Ventricular arrhythmia is frequently present in MVP. Increased severity of ventricular arrhythmia on ambulatory monitoring portends a worse prognosis in MVP patients. Ambulatory ECG monitoring should be considered for risk stratification in MVP patients.