Early feasibility study of catheter-free cardiac radioablation with proton beams for refractory ventricular tachycardia. - Siontis KC; Merrell KW; Deisher AJ; Shumway DA; Rettmann ME; Kapa S; Kowlgi GN; Asirvatham SJ; Welch EM; Kruse J; Foote RL; Packer DL (Heart rhythm, 2026)