Abstract 12892: Intracoronary Brachytherapy For Treatment of In-stent Restenosis in Drug Eluting Stents is Safe and Effective

Abstract

Background: Intracoronary brachytherapy (ICBT) is an effective treatment for restenosis (ISR) of bare metal stents (BMS) but its utilization has waned due to the advent of drug eluting stents (DES). ISR following DES occurs at a frequency of 10% or greater. The purpose of this study is to report on the results following ICBT for clinical ISR in patients with DES and to determine if there are predictors for its success. Materials/Methods: A retrospective analysis was performed to identify 135 patients treated on an IRB approved protocol using ICBT for DES ISR. All patients received ICBT after balloon angioplasty using Sr-90 with a centering balloon and an automated delivery device (Best Vascular Novoste System, Norcross, GA). A dose of 18.4Gy or 23Gy at 2mm depth was delivered based upon the diameter of the injured vessel. Coronary lesion location, length and diameter were evaluated at enrollment. Major adverse coronary events (MACE) defined by death, myocardial infarction, CVA, and target vessel revascularization (TVR) were the primary outcomes, while angina relief and repeat hospitalization were the secondary outcomes. Results: At 1 year, ICBT restenosis occurred in 27% of treated patients and MACE free survival was 13.6%. When comparing patients in whom restenosis after ICBT occurred, there was a higher association of post ICBT MI which remained significant after multivariate analysis. All other primary and secondary outcomes remained insignificant (Table 1 and 2). Conclusion: ICBT is safe and effective for the treatment of DES ISR. Very few alternatives other than coronary bypass surgery exist to treat DES ISR. Given the success of ICBT in DES ISR, we propose that it should be utilized as the primary therapy. Restenosis after ICBT appears to be associated with post-ICBT MI. Additional data is needed to determine if there are other predictors for ICBT success.