Importance of Arrhythmic Origin in the Diagnosis of Isolated Cardiac Sarcoidosis: A Case Report

Sarcoidosis has a heterogeneous clinical presentation and remains difficult to diagnose, especially in isolated cardiac sarcoidosis (CS). We report a case of life-threatening arrhythmia that led to the diagnosis of isolated CS. A 63-year-old man presented with sustained ventricular tachycardia that was thought to originate from the anterolateral free wall of the right ventricle. Electrocardiography, echocardiography, and coronary computed tomography performed after the return to sinus rhythm were initially considered unremarkable, but right ventricular free wall bulging was later noted on computed tomography. Follow-up echocardiography revealed abnormal wall motion not only in the right ventricular free wall but also in the left ventricular apex. The patient was finally diagnosed with isolated CS and was scheduled for steroid treatment after receiving an implantable cardioverter-defibrillator.