Risk factors for the development of restenosis following stent implantation of venous bypass grafts

Objective-To analyse the variables involved in the high restenosis rate fol lowing stent implantation in coronary artery bypass grafts. Design-A retrospective analysis of a consecutive group of patients attendin g a tertiary centre. Patients-The long term angiographic outcome of 219 stent implantations for individual lesions performed in 191 patients was investigated. Multivariate analysis correlated clinical, procedural, and angiographic variables with the incidence of angiographic restenosis, defined as diameter stenosis > 50 % at follow up. Results-Angiographic restenosis was observed in 34% of lesions treated. Mul tiple logistic regression analysis defined diabetes mellitus (odds ratio 6. 91, 95%, confidence interval (CI) 2.43 to 9.69), graft recanalisation (2.89 , 95% CI 1.18 to 6.63), lesion at the aortic anastomosis (6.98, 95% CI 2.77 to 21.31), lesion at the coronary anastomosis (3.01, 95% CI 1.19 to 7.69), high diameter stenosis after stent placement (7.21, 95%:, CI 2.66 to 16.81 ), placement of long stents (2.73, 95% CI 1.09 to 7.39), and implantation o f more than one stent (7.31, 95% CI 2.08 to 19.96) as independent predictor s of graft in-stent restenosis. Conclusions-There appears to be a specific risk factor constellation contri buting to the high restenosis rate following stent implantation in venous b ypass grafts. Critical consideration of these variables may help identify p atients who are poor candidates for stent implantation and who may benefit from a different approach.