A case report of arrhythmogenic mitral valve disease: still a long way to go

BACKGROUND: Mitral valve prolapse (MVP) is a common valvular heart disease and has often been associated with an increased risk of sudden cardiac death (SCD). This underlines the pressing need for the establishment of consistent tools for arrhythmic risk prediction. CASE SUMMARY: A 73-year-old man with previous diagnosis of MVP was referred to the cardiology outpatient consult for a 1-month history of near-syncope and light-headedness. He had no family history of SCD. Physical examination was unremarkable. Holter monitoring recorded frequent and multiple long episodes of non-sustained ventricular tachycardia (VT) and paroxysmal atrial fibrillation with controlled ventricular response. Echocardiogram revealed mitral bileaflet billowing, systolic curling, and annular disjunction, as well as increased peak systolic strain dispersion with two-dimensional speckle tracking. Cardiac magnetic resonance disclosed additional tricuspid annular dilatation and disjunction, as non-ischaemic late gadolinium enhancement on the left ventricular basal inferolateral wall. The Heart Team decided to implant a defibrillator as primary prevention for SCD due to arrhythmogenic mitral valve disease (AMVD) with high-risk features. The patient remained asymptomatic over the next 2 years, when he suffered an appropriate shock due to VT at 200 b.p.m. DISCUSSION: Here, we present a case of a patient with AMVD with classic features of high arrhythmic risk but also with some unusual characteristics such as older age, male gender, and only little pronounced mitral valve billowing, emphasizing the wide heterogeneity and lack of knowledge surrounding this entity.