Radioactive stents delay but do not prevent in-stent neointimal hyperplasia
BACKGROUND: Restenosis after conventional stenting is almost exclusively caused by neointimal hyperplasia. Beta-particle-emitting radioactive stents decrease in-stent neointimal hyperplasia at 6-month follow-up. The purpose of this study was to evaluate the 1-year outcome of (32)P radioactive stents with an initial activity of 6 to 12 microCi using serial quantitative coronary angiography and volumetric ECG-gated 3D intravascular ultrasound (IVUS). METHODS AND RESULTS: Of 40 patients undergoing initial stent implantation, 26 were event-free after the 6-month follow-up period and 22 underwent repeat catheterization and IVUS at 1 year; they comprised half of the study population. Significant luminal deterioration was observed within the stents between 6 months and 1 year, as evidenced by a decrease in the angiographic minimum lumen diameter (-0.43+/-0.56 mm; P:=0.028) and in the mean lumen diameter in the stent (-0.55+/-0. 63 mm; P:=0.001); a significant increase in in-stent neointimal hyperplasia by IVUS (18.16+/-12.59 mm(3) at 6 months to 27.75+/-11. 99 mm(3) at 1 year; P:=0.001) was also observed. Target vessel revascularization was performed in 5 patients (23%). No patient experienced late occlusion, myocardial infarction, or death. By 1 year, 21 of the initial 40 patients (65%) remained event-free. CONCLUSIONS: Neointimal proliferation is delayed rather than prevented by radioactive stent implantation. Clinical outcome 1 year after the implantation of stents with an initial activity of 6 to 12 microCi is not favorable when compared with conventional stenting.
|Keywords||*Brachytherapy/adverse effects/instrumentation, *Stents, Adult, Aged, Coronary Angiography, Coronary Disease/pathology/*radiotherapy/surgery, Endosonography, Female, Follow-Up Studies, Graft Occlusion, Vascular/diagnosis/*prevention & control/surgery, Humans, Male, Middle aged, Phosphorus Radioisotopes/adverse effects/*therapeutic use, Radiation Dosage, Research Support, Non-U.S. Gov't, Treatment Failure, Treatment Outcome|
Kay, I.P., Wardeh, A.J., Kozuma, K., Knook, A.H.M., Thury, A., Serruys, P.W.J.C., … Sianos, G.. (2001). Radioactive stents delay but do not prevent in-stent neointimal hyperplasia. Circulation (Baltimore), 103(1), 14–17. Retrieved from http://hdl.handle.net/1765/9562