Three-year clinical and angiographic follow-up after intracoronary radiation - Results of a randomized clinical trial

Background-Although several early trials indicate treatment of restenosis w ith radiation therapy is safe and effective, the long-term impact of this n ew technology has been questioned. The objective of this report is to docum ent angiographic and clinical outcome 3 years after treatment of restenotic stented coronary arteries with catheter-based Ir-192. Methods and Results-A double-blind, randomized trial compared Ir-192 with p lacebo sources in patients with previous restenosis after coronary angiopla sty, Over a 9-month period. 55 patients were enrolled; 26 were randomized t o Ir-192 and 29 to placebo. At 3-year follow-up, target-lesion revasculariz ation was significantly lower in the Ir-192 group (15.4% versus 48.3%; P<0. 01). The dichotomous restenosis rate at 3-year follow-up was also significa ntly lower in Ir-192 patients (33% versus 64%; P<0.05), In a subgroup of pa tients with 3-year angiographic follow-up not subjected to target-lesion re vascularization by the 6-month angiogram, the mean minimal luminal diameter between 6 months and 3 years decreased from 2.49+/-0.81 to 2.12+/-0.73 mm in Ir-192 patients but was unchanged in placebo patients. Conclusions-The early clinical benefits observed after treatment of coronar y restenosis with Ir-192 appeal durable at late follow-up. Angiographic res tenosis continues to be significantly reduced in Ir-192-treated patients, b ut a small amount of late loss was observed between the 6-month and 3-year follow-up time points. No events occurred in the Ir-192 group to suggest ma jor untoward effects of vascular radiotherapy. At 3-year follow-up, vascula r radiotherapy continues to be a promising new treatment for restenosis.