Autoimmune Myocarditis and Arrhythmogenic Mitral Valve Prolapse: An Unexpected Overlap Syndrome

Andrea Villatore,Antonio Esposito,Cristina Basso,Simone Sala,Paolo Della Bella,Davide Vignale,Giovanni Peretto,Stefano Stella,Elena Busnardo,Patrizio Mazzone

doi:10.3390/jcdd8110151

Abstract

Background: both myocarditis and mitral valve prolapse (MVP) are known uncommon causes of ventricular arrhythmias in young patients. Aim: to report the first clinical case of endomyocardial biopsy (EMB)-proven autoimmune myocarditis and associated arrhythmogenic MVP in a patient with recurrent ventricular fibrillation (VF) episodes. Methods: myocarditis was diagnosed both by cardiac magnetic resonance (CMR) and EMB. Arrhythmogenic MVP was documented by transthoracic echocardiogram, CMR, and electroanatomical mapping of the trigger premature ventricular contractions (PVCs). Results: a 22-year-old woman underwent immunosuppressive therapy after EMB-proven diagnosis of autoimmune myocarditis with VF onset and early implantable cardioverter defibrillator (ICD) placement. Three years later, she experienced two VF recurrences and persistent PVCs, despite no signs of myocarditis recurrence. An echocardiogram revealed bileaflet MVP with high arrhythmic risk features. Finally, electroanatomical mapping and ablation of the trigger PVC were successfully performed. Conclusion: in patients with recurrent VF episodes despite evidence-based medical treatment for myocarditis, MVP should be considered as an alternative arrhythmogenic substrate, and warrants early ICD implant and PVC-targeted therapy.

Highlights

The prevention of sudden cardiac death in young patients with structural diseases of the myocardium is still a challenge [1,2]
We report the case of a young woman, initially diagnosed with endomyocardial biopsy (EMB)-proven autoimmune myocarditis and presenting with recurrent ventricular arrhythmias (VA) late after immunosuppressive therapy (IST) withdrawal, who had mitral valve prolapse (MVP) as an overlapping arrhythmogenic substrate
To our knowledge, firstwoman case ofwith autoimmune myocarditis the diagnosis of MVP was known since her first clinical presentation, the initial diagnostic

Summary

Introduction

The prevention of sudden cardiac death in young patients with structural diseases of the myocardium is still a challenge [1,2]. Life-threatening ventricular arrhythmias (VA) have been described in patients with acute myocarditis [3], as well as in those with mitral valve prolapse (MVP) and additional risk features [4]. While the long-term arrhythmic risk of myocarditis is still unpredictable [8,9], a number of imaging parameters, including TTE and cardiac. Magnetic resonance (CMR), have been recently proposed to stratify the MVP arrhythmic risk [10,11]. We report the case of a young woman, initially diagnosed with EMB-proven autoimmune myocarditis and presenting with recurrent VA late after IST withdrawal, who had MVP as an overlapping arrhythmogenic substrate

Case Report

Diagnostic

Discussion

Conclusions