Steroid treatment deteriorated ventricular tachycardia in a patient with right ventricle-dominant cardiac sarcoidosis.

We report a case of a patient with cardiac sarcoidosis presenting with a non-sustained ventricular tachycardia (VT), mimicking arrhythmogenic right ventricular cardiomyopathy. After the pathological diagnosis and confirmation of gallium-67 uptake by the myocardium, corticosteroid therapy was initiated. The myocardial gallium accumulation disappeared shortly after the treatment, but the VTs deteriorated into multifocal and sustained VTs almost all day. Those drug-refractory VTs were finally controlled with 3 catheter ablation sessions.