BACKGROUND—Fatal arrhythmia is commonly observed in cardiac sarcoidosis, but clinical effects of a systematic treatment approach are still uncertain. This study sought to describe both clinical and electrophysiological characteristics and outcomes of systematic treatment approach to ventricular tachycardia (VT) associated with cardiac sarcoidosis. METHODS AND RESULTS—We enrolled 37 consecutive patients (11 men; age, 56±11 years) with a diagnosis of sustained VT associated with cardiac sarcoidosis. Clinical effects of a systematic treatment approach including medical therapy (both steroid and antiarrhythmic agents), in association with radiofrequency catheter ablation, were evaluated. All patients received antiarrhythmic agents, and 34 received steroid therapy. During a 39-month follow-up, 23 (62%) patients were free from any VT episodes with medical therapy. Multivariable Cox regression analyses revealed that the absence of gallium-67 myocardial uptake was an independent predictor for VT recurrence (hazard ratio, 7.51; 95% confidence interval, 1.65–34.26; P<0.01). Fourteen patients who experienced VT recurrences even while on drug therapy underwent radiofrequency catheter ablation. Electrophysiological study revealed that the mechanisms of VTs could be classified into 2 subgroupsPurkinje-related or scar-related VT. The QRS duration of VT was narrower in Purkinje-related than in scar-related VTs (157±23 versus 183±22 ms; P<0.05). After a 33-month follow-up subsequent to the radiofrequency catheter ablation, 6 of 14 patients experienced VT recurrence. The number of VTs sustained during electrophysiological study was higher in the patients with VT recurrence than in those without (3.7±1.4 versus 1.9±0.8; P<0.01). CONCLUSIONS—A systematic treatment approach to cardiac sarcoidosis with VT successfully suppressed VT recurrences in the majority of patients studied.