Abstract: Despite mitral valve prolapse is generally a benign condition, consistent data regarding it as cause of sudden cardiac death have been arisen. Among the poor-prognosis determinants, mitral annular disjunction plays a paramount role. We discuss the case of a young with mitral valve prolapse presented with resuscitated OHCA.
INTRODUCTION: Mitral valve prolapse (MVP) is the most common valvulopathy and its prognosis is usually excellent in the absence of relevant mitral regurgitation. However a recent meta-analisys demonstrated a significant link between MVP and sudden cardiac death (SCD). Among the features that raise the risk there is the mitral annular disjunction (MAD). MAD consists of the systolic separation of the mitral annulus from the ventricular myocardium at the level of the posterior leaflet. Independent from the presence of MAD, a recent scientific consensus has identified the elements which constitute the so called arrhythmic mitral valve complex/phenotype: 1) MVP 2) frequent or complex ventricular arrhythmias 3) absence of any other well-defined arrhythmic cause.
CASE PRESENTATION: A 32-year-old woman without any relevant medical history was collapsed; immediately her relatives called 118 and CPR was started. When the EMT arrived, the ECG showed ventricular fibrillation, and 6 DC shock were needed to restore spontaneous circulation. Once in the ED, she underwent urgent coronary angiography resulted negative. The ECG showed sinus rhythm at 65 bpm, infero-lateral negative T waves. A transthoracic echocardiogram (TTE) was carried out and it underlined a slightly depressed ventricular function (E.F. 53%), hypokinesia of the mid-apical septum, a mitral valve prolapse with moderate mitral regurgitation and mitral annular disjunction of 10mm, data concordant with the cardiac magnetic resonance (CMR) and transoesophageal echocardiography (TEE) thereafter performed. Viral and autoimmune screenings resulted negative. The patient underwent dual chamber TV-ICD implantation in secondary prevention.
DISCUSSION: AMVP is a challenging entity because of the need of early identification of the patients affected by the arrhythmic phenotype for whom is indicated a lifelong follow up and in selected cases ICD implantation in primary prevention of SCD. Even if globally rare, SCD among patients affected by MVP is not a statistically dismissible event and in the small available post mortem studies it accounts for 4% to 7% of otherwise unexplained deaths.