High-Dose Intracoronary Irradiation after De Novo Stent Implantation

Abstract

This randomized study was designed to compare the efficacy of high-dose coronary β-radiation after intravascular ultrasound-(IVUS-)guided direct stenting with sham treatment in patients with de novo lesions. 32 patients were enrolled in the study protocol. Following angioplasty procedure, intracoronary brachytherapy was performed with the Novoste™ Beta-Cath System. The prescribed dose was 24 Gy referred to the lamina elastica externa. Quantitative coronary angiography and IVUS were performed to analyze the treated coronary vessel. Angiographic results revealed a significantly smaller minimal lumen diameter compared with the postprocedural minimal lumen diameter within the stented segment (p = 0.004) in the nonirradiated group. The same significant result was observed in the injured segment of the nonirradiated patients (p = 0.011). The IVUS data revealed a significant increase of the plaque volume after 8 months in the nonirradiated group compared to the postprocedural value (irradiated 5.41 ± 8.83 mm3 vs. nonirradiated 21.11 ± 16.08 mm3; p = 0.001). Late luminal loss was significantly greater in the nonirradiated group (p = 0.004). The primary clinical endpoint (death, myocardial infarction, repeat target lesion revascularization, percutaneous revascularization, coronary artery bypass surgery) was reached by seven irradiated (33.3%) and four (18.2%) nonirradiated patients (p = 0.623). Late stent thrombosis was observed in one irradiated patient. The EVEREST trial has demonstrated the feasibility of high-dose intracoronary brachytherapy in de novo coronary lesions. There is a significant reduction of neointimal proliferation within the stented segment. Nevertheless, this benefit is vitiated by an increase of restenotic lesions outside the stent segment.