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

Background Patients 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). Methods We 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. Results We 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. Conclusions In 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. ### Competing Interest Statement The authors have declared no competing interest. ### Clinical Trial N/A ### Funding Statement No external funding ### Author Declarations I confirm all relevant ethical guidelines have been followed, and any necessary IRB and/or ethics committee approvals have been obtained. Yes The details of the IRB/oversight body that provided approval or exemption for the research described are given below: University of Michigan IRB I confirm that all necessary patient/participant consent has been obtained and the appropriate institutional forms have been archived, and that any patient/participant/sample identifiers included were not known to anyone (e.g., hospital staff, patients or participants themselves) outside the research group so cannot be used to identify individuals. Yes I understand that all clinical trials and any other prospective interventional studies must be registered with an ICMJE-approved registry, such as ClinicalTrials.gov. I confirm that any such study reported in the manuscript has been registered and the trial registration ID is provided (note: if posting a prospective study registered retrospectively, please provide a statement in the trial ID field explaining why the study was not registered in advance). Yes I have followed all appropriate research reporting guidelines, such as any relevant EQUATOR Network research reporting checklist(s) and other pertinent material, if applicable. Yes All data available on request * AMVPS : arrhythmogenic mitral valve prolapse syndrome CI : confidence interval CMR : cardiac magnetic resonance imaging DE : delayed enhancement EF : ejection fraction EPS : electrophysiology study ICD : implantable cardiac defibrillator LV : left ventricle MAD : mitral annular disjunction MV : mitral valve MVP : mitral valve prolapse OR : odds ratio PVC : premature ventricular contraction RV : right ventricle SCA : sudden cardiac arrest SD : standard deviation TWI : T wave inversion VA : ventricular arrhythmias VF : ventricular fibrillation VT : ventricular tachycardia