Abstract 11502: Exercise Stress Testing for Arrhythmic Mitral Valve Prolapse

Abstract

Background - Mitral valve prolapse (MVP) is a common valvular abnormality found in approximately 2.4% of the population. Whereas the majority of cases are benign, an increasingly recognized sequela of MVP is sudden cardiac death (SCD), but triggers and risk factors for SCD are not well-defined. It is theorized that increased stretch on the papillary muscles due to MVP leads to papillary muscle fibrosis and cellular changes of local conduction properties, increasing the risk of ventricular arrhythmias and SCD. Hypothesis - We hypothesized that patients with MVP and SCD would have increased ventricular arrhythmias and ECG changes compared to MVP controls during exercise stress testing. Methods - The study population was generated from the Duke Epic. Patients were included if they had guideline-based diagnosis of MVP on echocardiogram or cardiac magnetic resonance imaging. Increase in ventricular arrhythmias during exercise was defined as >/= 10 PVCs per minute, multifocal PVCs, or >/= 2 PVCs in a row. Results- A total 2,513 patients with MVP were screened. 18 patients with SCD. Patients with SCD were younger [(47.22 +/- 12.2 ) vs. (58.0 +/- 18.7), p=0.02], more likely to be female (89.9% vs 64%, p=0.04) and had increased rate of bileaflet prolapse (72% vs. 40%, p=0.01) compared to controls. Patients with sudden cardiac death had either dynamic T wave changes or increased ventricular arrhythmias with stress testing versus controls [12/18 (66.7%) vs 17/75 (22.6%), p <0.001]. Conclusions - Increased ventricular arrhythmias on exercise stress testing is associated with sudden cardiac death in mitral valve prolapse and may prove a useful tool for further risk stratification.