Risk Factors for Sudden Cardiac Arrest and Ventricular Arrhythmias in Arrhythmogenic Mitral Valve Prolapse Syndrome

BackgroundPatients with the arrhythmogenic mitral valve prolapse syndrome (AMVPS) are at increased risk for life-threatening ventricular arrhythmias (VAs), but studies have been limited by small sample sizes. We sought to assemble an international AMVPS registry to delineate clinical, imaging, treatment characteristics, and risk factors for sudden cardiac arrest (SCA). MethodsWe retrospectively identified two groups of subjects with AMVPS: 1) the MVP-SCA group with SCA, sustained ventricular tachycardia (VT), and ventricular fibrillation (VF); and 2) the MVP-PVC group with significant premature ventricular complexes (PVCs) only. Deidentified data was abstracted locally and combined centrally. ResultsWe included 217 subjects with AMVPS: 148 (68%) had SCA or VT/VF (MVP-SCA group) and 69 (32%) had PVCs only (MVP-PVC group). Phenotypically, both groups were similar [mean age 44.2{+/-}16.7 years, 66% female, 76% with bileaflet prolapse, 55% with mitral annular disjunction (MAD)]. Syncope was more common in the MVP-SCA group than the MVP-PVC group (47% vs 22%, p=0.001) as were anterolateral T-wave inversions (TWIs, 22% vs 7%, p=0.011). Prior mitral valve surgery was less common in the MVP-SCA group (6% vs 20%, p=0.002). These differences remained significant after multivariable adjustment. An electrophysiology (EP) study was negative in 15/45 (33%) of the MVP-SCA subjects. ConclusionsIn this international registry, AMVPS subjects were young, female, and had bileaflet prolapse with MAD. A history of syncope and anterolateral TWIs were associated with SCA. Prior mitral valve surgery was less common in SCA subjects. A negative EP study had limited negative predictive value in high-risk patients.