Inclusion Criteria:  Diagnosis of Chagas heart disease including positive serology Recurrent sustained ventricular tachycardia requiring therapy due to symptoms, ICD shocks, or requiring hospitalization. Age>18 years. Able to give written, informed consent. If the patient requires continuous sedation/anesthesia for arrhythmia control consent can be provided by the next of kin. Medically fit to undergo radiation planning and treatment sessions. Failed antiarrhythmic medications due to VT recurrence, drug intolerance, or contraindication. Failed prior catheter ablation due to arrhythmia recurrence or ineligible for endocardial or epicardial catheter ablation (LV thrombus, epicardial adhesion, megacolon, prior open chest surgery)  Exclusion Criteria:  Cardiogenic shock not due to VT with no possibility of heart transplant or ventricular assist device. Inability for patient to be adequately immobilized for radiation planning and treatment. Repeat catheter ablation is felt to be a reasonable option. Previous radiation to the chest. Pregnancy or refusal to use contraception.