Balloon‐based radiation therapy for treatment of in‐stent restenosis in human coronary arteries: Results from the BRITE I study

Catheter‐based intracoronary radiation therapy demonstrated reduction of the recurrence rate of in‐stent restenosis by 35%–50% when compared to conventional therapy. The objectives of this study were to determine the safety and feasibility of a new balloon‐shaped source design and a higher applied dose to reduce the restenosis rates. Thirty‐two patients with in‐stent restenosis who met study eligibility criteria were successfully treated with standard PCI techniques. Following a successful intervention, a P‐32 β‐balloon source was positioned to cover the angioplasty site and a dose of a 20 Gy at 1 mm from the surface of the source was administered. The primary endpoint was a composite of major adverse cardiac events (any death, MI, emergent CABG, or repeat target vessel revascularization) during 6 months of follow‐up. At 6 months, only one patient underwent repeat PTCA to the target vessel (3%). There were no instances of death, emergency surgery, late thrombosis, total occlusions, or MI. Binary restenosis measured by QCA at the stented segment was 0% and for the whole analysis vessel was 7.5%. Beta‐radiation delivered with a balloon P‐32 source design for patients with in‐stent restenosis results in lower than expected rate of angiographic and clinical restenosis and the absence of late complications. Cathet Cardiovasc Intervent 2002;57:286–294. © 2002 Wiley‐Liss, Inc.