# Mitral Annular Disjunction Presenting With Ventricular Arrhythmia: A Case Report

## TL;DR

A patient with ventricular arrhythmias and normal coronary arteries was found to have mitral annular disjunction, highlighting its role in arrhythmias and the importance of advanced imaging for diagnosis.

## Contribution

This case report emphasizes MAD as a potential cause of ventricular arrhythmias and demonstrates the value of CMR in diagnosing MAD and guiding management.

## Key findings

- CMR confirmed mitral annular disjunction and adjacent papillary muscle fibrosis in a patient with non-sustained ventricular tachycardia.
- The patient had preserved left ventricular systolic function and no evidence of ischemia or myocarditis.
- Multimodality imaging, especially CMR, is critical for identifying arrhythmogenic substrates in MAD.

## Abstract

Mitral annular disjunction (MAD) is an underrecognized structural abnormality increasingly linked to ventricular arrhythmias and sudden cardiac death. We report the case of a patient admitted for palpitations and chest discomfort, in whom a 12-lead surface electrocardiogram captured a short episode of ventricular tachycardia that terminated spontaneously, consistent with non-sustained ventricular tachycardia (VT). Coronary angiography demonstrated normal coronary arteries, prompting further evaluation with cardiac magnetic resonance imaging. CMR revealed a clear systolic separation between the posterior mitral annulus and the left ventricular myocardium, confirming the presence of MAD. It also identified focal papillary muscle fibrosis adjacent to the disjunction, an arrhythmogenic substrate strongly associated with malignant ventricular arrhythmias, with no evidence of ischemia or myocarditis. Left ventricular systolic function was preserved. The patient was started on medical therapy and referred for electrophysiological assessment due to the arrhythmic burden and high-risk structural findings. This case highlights the importance of considering MAD in patients presenting with ventricular arrhythmias despite normal coronary angiography. Multimodality imaging, particularly CMR, plays a pivotal role in identifying both structural and tissue abnormalities, refining risk stratification, and guiding management. Early recognition of MAD enables targeted follow-up, optimized therapy, and timely intervention to reduce the risk of life-threatening outcomes.