Near-Fatal Arrhythmia From Severe Mitral Annular Disjunction.

Mitral annular disjunction (MAD) is increasingly recognized as a structural abnormality associated with ventricular arrhythmias and sudden cardiac arrest, particularly in the setting of bileaflet mitral valve prolapse (MVP). A 43-year-old man with a history of migraines presented following a witnessed out-of-hospital cardiac arrest and was successfully resuscitated with a single AED shock. Transthoracic echocardiography showed mitral regurgitation with bileaflet prolapse and suspected MAD. An implantable cardioverter-defibrillator was placed for secondary prevention, and the patient was discharged in stable condition with outpatient surgical follow-up where robotic-assisted mitral valve repair was successfully performed. Advanced imaging plays a pivotal role in diagnosis and risk stratification when MAD presents as sudden cardiac arrest.