The Arrhythmogenic Spectrum of Mitral Valve Disease: Pathophysiology, Risk Stratification, and Surgical Management

Mitral valve prolapse (MVP) is generally associated with excellent long-term outcomes when MR is absent or mild. Nonetheless, a small proportion of patients exhibit a distinct arrhythmogenic susceptibility, characterized by complex ventricular ectopy, sustained ventricular arrhythmias (VAs), and in rare instances, sudden cardiac death (SCD). This subgroup-collectively referred to as arrhythmic MVP (AMVP)-has prompted renewed attention in identifying individuals at elevated risk. Among the structural alterations associated with MVP, mitral annular disjunction (MAD) has gained recognition as a major contributor to arrhythmic vulnerability, arising from the pathological separation of the posterior annulus from the adjacent ventricular muscle. Advances in multimodality imaging, including trans-thoracic echocardiography (TTE), cardiac magnetic resonance (CMR), and cardiac computed tomography (cCT), have significantly improved delineation of MAD and clarified its relationship to the broader MVP spectrum. Current evidence suggests that MVP, MAD, and AMVP should not be regarded as isolated conditions but as intersecting phenotypes within a shared pathological framework. In certain patients, especially those without established myocardial fibrosis, abnormal annular dynamics appear to constitute the primary arrhythmogenic driver and may diminish after surgical intervention. In others, persistent arrhythmias despite optimal repair reflect a fibrosis-based substrate. This review synthesizes contemporary insights into the anatomical, biomechanical, and electrophysiological interplay linking MVP, MAD, and ventricular arrhythmogenesis, emphasizing implications for imaging-based risk assessment and individualized surgical management strategies.