Ventricular Tachycardia as the Initial Presentation of Tuberculous Myocarditis

BACKGROUND: Myocardial involvement in tuberculosis is exceptionally rare and may closely mimic cardiac sarcoidosis, particularly when presenting with ventricular arrhythmias. CASE SUMMARY: A 47-year-old man from a tuberculosis-endemic region presented with sustained monomorphic ventricular tachycardia and biomarker elevation. Coronary angiography was normal. Multimodal imaging demonstrated extensive inflammatory nonischemic myocardial involvement and mediastinal lymphadenopathy. Initial lymph node biopsy showed nonnecrotizing granulomas, leading to a working diagnosis of probable cardiac sarcoidosis and initiation of corticosteroid therapy. Delayed lymph node culture later identified Mycobacterium tuberculosis, prompting revision of the diagnosis and initiation of antituberculous therapy. Despite microbiologic control, recurrent ventricular tachycardia required antiarrhythmic optimization and catheter ablation. DISCUSSION: This case highlights the diagnostic overlap between tuberculous myocarditis and cardiac sarcoidosis and underscores the importance of microbiologic confirmation in patients from endemic regions. TAKE-HOME MESSAGES: Tuberculosis should be considered in granulomatous myocarditis with ventricular arrhythmias. Multimodal imaging combined with extracardiac tissue culture may be decisive in establishing the correct diagnosis.