Long-Term Outcomes after Treatment of Diffuse In-Stent Restenosis with Rotational Atherectomy Followed by Beta-Radiation Therapy with a 188Re-MAG3-Filled Balloon

ABSTRACT

BACKGROUND AND OBJECTIVES: Intracoronary radiation therapy for in-stent restenosis has been demonstrated to reduce restenosis and major adverse cardiac events. However, the long-term angiographic and clinical outcomes after beta radiation therapy have not been sufficiently evaluated. SUBJECTS AND METHODS: The long-term angiographic and clinical outcomes of 50 consecutive patients who had received beta-radiation therapy with an 188Re-MAG3-filled balloon after rotational atherectomy for diffuse in-stent restenosis (lesion length>10 mm) in native coronary arteries were evaluated. The radiation dose was 15 Gy at a depth of 1.0 mm into the vessel wall. RESULTS: The mean lesion length was 25.6+/-12.7 mm. Radiation was delivered successfully to all patients, without any procedural or in-hospital complications. At the 6-month angiogram, the restenosis rate was 10% (5/50). There were no major adverse cardiac events (MACE), such as death, myocardial infarction or target lesion revascularization (TLR), by the 6-month follow-up. Long-term clinical data were obtained from all patients during 30.1+/-4.5 months of follow-up. No myocardial infarction and one noncardiac death occurred during follow-up. A two-year follow-up angiogram was performed in 26 (58%) of 45 patients that showed a patent radiation segment at the 6-month angiogram. Significant narrowing of the diameter stenosis greater than 50% occurred in 6 (23%) of 26 patients between 6- and 24-months after the beta-radiation. Late TLR was performed in 6 patients. The rate of 30-month death-free survival and MACE-free survival were 98.0+/-2.0 and 86.9+/-5.0%, respectively. CONCLUSION: Beta-radiation using an 188Re-MAG3-filled balloon after rotational atherectomy is associated with favorable long-term angiographic and clinical outcomes.