Intracoronary beta-radiation of de novo coronary lesions using a (186)Re liquid-filled balloon system: six-month results from a clinical feasibility study.

Vascular brachytherapy has shown to be effective for in-stent restenosis, but efficacy in de novo lesions remains uncertain. We evaluated feasibility and outcome of intracoronary beta-radiation therapy in de novo coronary lesions using a (186)Re liquid-filled balloon system. Thirty-three patients received 20 Gy (186)Re beta-radiation immediately after balloon angioplasty. The 6-month restenosis rate was 41% (12/29) and restenosis was located within the target lesion in eight patients and at the edges of the injured and irradiated segment, outside the target lesion, in four patients. At 6 months, four patients (12%), all stented during the initial procedure, had experienced a late (> 30 days) total occlusion. Intracoronary beta-radiation therapy of de novo coronary lesions using (186)Re is technically feasible. No reduction in restenosis was observed. The high incidence of late total occlusions may have been prevented by avoiding new stent implantation and prolonging double antiplatelet therapy.