Compassionate use of intracoronary beta-irradiation for treatment of recurrent in-stent restenosis

Recurrent in-stent restenosis after balloon angioplasty poses a serious man agement problem. previously gamma-radiation has been shown to be effective in patients with in-stent restenosis. The aim of the study was to determine the feasibility and safety of beta-radiation in patients with recurrent in -stent restenosis. From May 1997 to December 1998, 18 patients were treated with balloon angioplasty (n = 8) or laser (n = 10), followed by intracoron ary beta-radiation at a prescribed dose of 16 Gray at 2 mm from the source, for reference diameters by quantitative coronary angiography < 3.25 mm or 20 Gray for reference diameters greater than or equal to 3.25 mm. Vessels t reated were as follows,vs: left anterior descending: (n = 5); circumflex: ( n = 4); right coronary artery: (n = 6); saphenous vein graft: (n = 3). Aver age recurrence rate was 2.4 +/- 0.7 and the restenotic length was 16 +/- 7 mm. beta-radiation was successfully delivered in all patients. Two patients presented complications related to laser debulking: a non-Q wave myocardia l infarction in one and a re-angioplasty due to uncovered distal dissection in another. Geographical miss, defined as an area which has been injured b ut not covered by the radiation source, was demonstrated in 8 patients. Sev enteen patients (94%) completed the 6-month angiographic follow-up. Resteno sis (> 50% Diameter Stenosis) was observed in 9 patients (53%), leading to target lesion revascularization in 8 patients (47%). Six of the 9 restenose s were located in areas with geographical miss. Intracoronary beta-radiatio n for recurrent in-stent restenosis appears to be a safe and feasible manag ement strategy. However, the mismatch between injured and irradiated area m ay lead to failure of this therapy.