SummaryThe authors report the case of a 67-year-old woman, with mitral valve prolapse, for more than 20 years. She recently complained of attacks of syncope and clinical ventricular tachycardia; ventricular fibrillation was induced during programmed stimulation. The patient seemed to be at high risk for sudden cardiac death, and was therefore treated with an automatic implantable defibrillator. The pathophysiology and risk factors of sudden cardiac death in mitral valve Prolapse are discussed.