Coronary chronic total occlusions

Abstract

There are limited data on the mid-term safety following the use of the guided-subintimal tracking and re-entry (guided-STAR) technique for the treatment of chronic total occlusions (CTO) and concerns have arisen about a potential increased risk of stent thrombosis (ST). The aim of this study was to evaluate the mid-term safety in terms of cardiac death and ST after recanalization using the contrast guided-STAR technique when compared to conventional anterograde CTO recanalization (CA-CTO). This retrospective study analyzed 355 consecutive patients with successful angiographic recanalization (residual stenosis <20% and TIMI flow grade ≥2) of CTO lesion. Seventy-four (20.8%) underwent guided-STAR and 281 (79.2%) had CA-CTO. Survival rates were estimated using the Kaplan-Meier method. Compared to CA-CTO patients, the rate of the following clinical, angiographic, and procedural characteristics were significantly higher in guided-STAR patients: hypercholesterolemia (84 vs. 67%, P = 0.004), previous CABG (41.3 vs. 15.7%, P < 0.0001), three-vessel disease, (62.7 vs. 47%, P = 0.019), right coronary artery CTO (62.7 vs. 41.6%, P = 0.002), stent length (68.15 vs. 54.05 mm, P < 0.0001). A drug-eluting stent was implanted in the majority of cases (89.2% guided-STAR vs. 93.5% CA-CTO). At a median follow-up of 779 days (IQR 495-1035), there were no significant differences in cardiac survival (97.2 vs. 97.5%, Log-rank P = 0.912) and cumulative ARC ST rates (2.8 vs. 1.8%, Log-rank P = 0.610) for guided-STAR and CA-CTO patients, respectively. The rate of restenosis was significantly higher in the guided-STAR group compared to the CA-CTO group (54 vs. 30%, Log-rank P < 0.0001). The adjusted Cox proportional-hazard analysis for procedural technique showed that the only significant independent predictor of restenosis was the stent length (HR, 1.017; 95% CI, 1.008-1.027; P < 0.0001). At mid-term follow-up, the guided-STAR was not inferior to CA-CTO in terms of safety. The only significant independent predictor of restenosis was the stent length.