Trial in Arrhythmia Radioablation for Ventricular Tachycardia: Single Fraction vs Three Fractions

This is a research study that aims to understand if giving a lower dose of treatment all at once is as effective and safe as dividing it into three smaller doses for patients with a heart condition called refractory ventricular tachycardia (VT). These patients have not exhibited positive responses to conventional medications or procedures. This study aims to explore whether an alternative approach could yield more beneficial outcomes.

Ventricular tachycardia (VT) is a life-threatening heart rhythm disorder that arises from areas of diseased tissue in the heart. Treatment of VT can involve anti-arrhythmic drugs and catheter-based ablations. Unfortunately, despite multiple antiarrhythmic drugs, as well as the catheter-based ablation procedures, VT continues to persist in your case. At this point in time, The investigators believe that stereotactic body radiotherapy (SBRT) remains the only possible option to potentially treat VT. The investigators hypothesize that by administering SBRT at different dose levels and fractionation may achieve a better therapeutic ratio, defined as comparable efficacy with less risk of toxicity due to lower dose exposure to the normal tissue, including the heart vasculature, in patients when compared to VT patients who receive a dose of 25Gy in a single fraction which is the current treatment option. This is a randomized dose de-escalation trial where the patients will be randomized in in one of the two experimental arms, receiving 1 single fraction OR 3 daily consecutive fractions of RT, and will be treated into a prespecified dose level group, based on the study development. The study includes three de-escalated consecutive dose level groups for each of two randomized treatment arms and there will be 3 patients per group and each group will receive a particular radiation treatment either as single treatments or three treatments. The purpose of this treatment is to safely reduce episodes of VT.