Cardiac MRI unveils the hidden storm: Myocarditis-induced ventricular tachycardia in a young patient with a structurally normal heart.

Myocarditis is an underrecognized cause of malignant ventricular arrhythmias, particularly in young adults with preserved cardiac structure on initial evaluation. We report a 37-year-old previously healthy man who presented with hemodynamically unstable ventricular tachycardia accompanied by significant troponin elevation but normal coronary arteries and preserved left ventricular systolic function on echocardiography. The arrhythmia initially mimicked idiopathic fascicular ventricular tachycardia. Cardiac magnetic resonance imaging subsequently revealed subepicardial late gadolinium enhancement and myocardial edema, establishing the diagnosis of acute myocarditis as the arrhythmogenic substrate. Therapy was adjusted with good clinical stability and no recurrence of arrhythmia. This case underscores the diagnostic challenges and the value of cardiac magnetic resonance imaging in unexplained ventricular tachycardia and emphasizes the importance of thorough history followed by etiology-directed management in myocarditis-related arrhythmias, and that clinicians must maintain a high index of suspicion for myocarditis in similar presentations.