Predictors of stent fracture in patients treated with closed-cell design stents

Abstract

The aim of this study was to evaluate the predictors of coronary stent fracture in patients treated with closed-cell design stents including the sirolimus-eluting stent (SES) and its bare-metal platform, Bx velocity stent (BVS). Various mechanical factors have been considered to be the predictors of stent fracture, especially in patients treated with SES. However, it is unknown whether SES is more prone to fracture compared with BVS. We retrospectively analyzed 391 lesions treated with SES or BVS in 339 patients who underwent follow-up coronary angiography. A total of 30 stent fractures (7.7%) in 28 patients treated with 29 SES (96.7%) and one BVS (3.3%) was found. On univariate analyses, stent fracture was related to angulated lesions (>45°) during diastole, longer stent, larger number of stents per lesion (P<0.001), right coronary artery (RCA) placement (P=0.008), and SES (P=0.016). On multivariate analyses, however, angulated lesion (odds ratio: 6.73; 95% confidence interval: 2.71-16.71; P<0.001) and RCA placement (odds ratio: 2.82; 95% confidence interval: 1.03-7.72; P=0.044) served as independent predictors of stent fracture while SES (P=0.080) and total stent length (P=0.069) showed only trends that did not reach statistical significance. This study showed that fracture of SES or BVS with the same closed-cell design platform was related to angulated lesion and RCA placement, but SES itself was not an independent predictor of stent fracture.