Abstract 11350: Arrhythmogenic Mitral Valve Prolaspe and Mitral Annular Disjunction

Abstract

Background: Mitral valve prolapse (MVP) affects about 2-3% of the general population. A small proportion of persons may have arrhythmic symptoms, leading to ventricular arrhythmias and sudden cardiac death (SCD). Mitral annular disjunction is a recently described entity that may be present with MVP or independently. Case: A 55-year-old male patient presented to the hospital with cardiac arrest. He has a history of percutaneous coronary intervention with stenting to left anterior descending (LAD) and right coronary artery (RCA) in 2015. He had ventricular fibrillation (VF) and subsequently arrested and underwent resuscitation. Electrocardiogram (EKG) showed sinus rhythm with prolonged QTc 487msec with no ischemia; echocardiography showed mitral annular disjunction, severe left ventricular global hypokinesis with ejection fraction of 10%. Left heart catheterization revealed nonobstructive moderate coronary artery disease. Right heart catheterization showed a severely reduced cardiac index of 2.1, and he was placed on mechanical support (Impella) for cardiogenic shock. On day 5, repeat echocardiography revealed left ventricular ejection fraction of 60%. Subsequent cardiac magnetic resonance (CMR) showed no evidence of infiltrative diseases but revealed an inferolateral wall scar from previous myocardial infarction and MVP with MAD. An implantable cardiac defibrillator was placed for secondary prevention of SCD. Discussion: The potential etiology of our patient's ventricular fibrillation cardiac arrest may include a scar from previous myocardial infarction or arrhythmogenic MVP with MAD. Myocardial fibrosis arising from MAD may be an origin of ectopic activity and arrhythmia. EKG, echocardiographic, and cardiac magnetic resonance imaging (CMR) are essential in diagnosing arrhythmic MVP and MAD. Young patients with premature ventricular contractions without clear etiology should be evaluated for MAD, and incidental findings of MAD should warrant further investigations, given its arrhythmogenic potential. Conclusion: MVP with MAD is associated with life-threatening arrhythmias. Further studies are required to explore treatment options to reduce the incidence of malignant VAs and SCDs in patients with MVP.