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

Area of Science:

• Cardiology
• Cardiac Electrophysiology
• Cardiovascular Imaging

Background:

• Mitral valve prolapse (MVP) typically has good outcomes unless significant mitral regurgitation (MR) is present.
• A subset of MVP patients, termed arrhythmic MVP (AMVP), are susceptible to ventricular arrhythmias (VAs) and sudden cardiac death (SCD).
• Mitral annular disjunction (MAD), a separation of the posterior annulus from ventricular muscle, is increasingly recognized as a significant contributor to arrhythmic vulnerability in MVP.

Purpose of the Study:

• To review the current understanding of the relationship between MVP, MAD, and ventricular arrhythmogenesis.
• To highlight the role of multimodality imaging in identifying MAD and assessing risk in AMVP patients.
• To discuss the implications for risk stratification and personalized surgical management.

Main Methods:

• Synthesis of contemporary evidence from anatomical, biomechanical, and electrophysiological studies.
• Review of advances in multimodality imaging techniques (TTE, CMR, cCT) for MAD delineation.
• Analysis of the interplay between structural abnormalities and arrhythmogenesis in MVP.

Main Results:

• MVP, MAD, and AMVP represent intersecting phenotypes within a shared pathological framework.
• Abnormal annular dynamics can be the primary arrhythmogenic driver in some patients, potentially improving post-surgery.
• Persistent arrhythmias in others may indicate a fibrosis-based substrate, even after surgical repair.

Conclusions:

• MAD is a critical factor in the development of ventricular arrhythmias in a subset of MVP patients.
• Multimodality imaging is essential for identifying MAD and guiding risk assessment.
• Individualized surgical strategies considering both annular dynamics and myocardial fibrosis are crucial for managing AMVP.