The Effects of a Carbon Ion Implantation Technique on In-stent Restenosis: Korean Multicentered Randomized Trial

ABSTRACT

BACKGROUND AND OBJECTIVES: Heavy metal ions released from a stainless steel stent can induce an inflammatory reaction that might be associated with in-stent restenosis. A carbon ion implantation technique, which physically integrates carbon ions into the surface of the stainless steel lattice, can block heavy metal ion diffusion, and improve the biocompatibility. This study was designed to evaluate the efficacy of a carbon ion implanted Arthosinert stent on the reduction of in-stent restenosis and the improvement in the clinical outcomes. SUBJECTS AND METHODS: 193 de novo coronary lesions in 191 anginal patients at 14 centers, with reference diameters from 2.75 to 4.5 mm, were randomly assigned to either an Arthosinert (100 patients, 102 lesions) or an Arthos (91 patients, 91 lesions) stent. The lesion length was 14.1+/-5.7 mm. The ACC/AHA (American College of Cardiology/American Heart Association) lesion classifications were A15.0%, B136.8%, B235.8% and C12.4%. The study end points are angiographic restenosis, during a six-month follow-up, and Major adverse cardiac event. In-stent restenosis was defined as a diameter of stenosis > or =50%. RESULTS: A six-month angiographic follow-up was obtained for 72.3% (138/191) of the subjects. There were no significant differences between the Arthosinert and Arthos groups in the rates of restenosis (17.8% vs. 31.8%, p=0.055) and Target vessel revascularization (7.0% vs. 11.0%, p=0.476). There were no deaths or non-fatal myocardial infarction in either group. CONCLUSION: The treatment of de novo coronary stenosis, with carbon ion implanted stents, showed a tendency for lower six-month angiographic restenosis rates than the conventional 316L stainless steel stents. A larger trial will be needed to confirm the efficacy of the carbon ion implanted stent.