Beta-radiation for coronary in-stent restenosis

To determine the feasibility and safety of an intracoronary beta-radiation device in preventing the recurrence of in-stent restenosis (ISR) after succ essful angioplasty, we studied 37 patients treated with beta-radiation (30- mm strontium-90 source) after angioplasty. The mean reference diameter was 2.9 +/- 0.5 mm, and 62% of lesions were diffuse, including four total occlu sions. Beta-radiation was successfully delivered in 36 of 37 (97%) cases. O ver the course of 7.1 +/- 4.5 mo follow-up, there were no myocardial infarc tions and three deaths: one from preexisting malignancy, one from progressi ve cardiac failure, and one from sudden cardiac death. Target vessel revasc ularization (TVR) was performed in seven of 36 (19%) patients. Thirty patie nts underwent angiography at 6 mo; three (10%) experienced restenosis (diam eter stenosis > 50%) at the target site, four (13%) had edge stenoses, and two (7%) had late (> 1 mo) thrombotic occlusions. Beta-radiation for ISR is associated with encouragingly low rates of target lesion restenosis and TV R. Further improvements are needed to solve the limitations of the edge eff ect and late occlusion. Cathet Cardiovasc. Intervent 51:422-429, 2000. (C) 2000 Wiley-Liss, Inc.