ABSTRACT
Background: Stereotactic radiotherapy (SBRT) is a new therapeutic option for patients with scar related ventricular tachycardia (VT). Objective(s): To describe our experience with the use of SBRT for the treatment of recurrent VT in patients with Chagas Cardiomyopathy (CCM) in whom catheter ablation is not an option. Method(s): We selected patients with Chagas Disease that underwent SBRT for recurrent VT treatment. The target sites of SBRT were planned based on CMR and CT reconstruction on ADAS software, bipolar voltage maps from previous CA procedures and VT morphology induced on a electrophysiologic study performed SBRT planning. Target sites were decided together by electrophysiology and radiation oncology group. Result(s): We performed SBRT in six CCM patients July 2021 to July 2022. Most patients were male (66.7%), mean age 62.3+/-5.7 years-old and EF 28.5% (Q1: 20 Q3:42.7). One patient (16.7%) had two prior catheter ablation, four (66.7%) had one and one patient had no prior ablation, but had severe pulmonary fibrosis after COVID and was O2 dependent. The mean PTV (planning target volume) was 85+/-14 mL and the ITV (internal target volume) was 29+/-4 ml, with safe constraints regarding the esophagus and stomach. In a mean FU of 244+/-173days, 3 (50%) patients presented VT recurrence after blanking period. Two patients died 86 and 50 days after SBRT. The median number of VT episodes reduced from 13 (6.25;44.75) to 7.5 (3;7.5) (P = 0.093). All alive patients stop presenting VT in a median period of 174 (Q1: 44.75: Q3: 199) days, being at the end of the follow-up in a median of 196 (Q1: 137;Q3: 246) days without new VT episodes. Conclusion(s): SBRT presents a high rate of early recurrence in Chagas disease patients that improves during timeCopyright © 2023