Long-term outcomes of drug-eluting stents versus bare-metal stents in large coronary arteries

Background Long-term (> 3 years) outcomes of drug-eluting stents (DES) versus bare-metal stents (BMS) in large coronary arteries were not conclusive. In addition, large coronary vessels were defined using a wide size range (≥ 3.0 mm) in previous studies. The aim of this study was to assess the long-term efficacy of DES versus BMS in subgroups of different vessel sizes. Methods A total of 1096 patients (1342 lesions) who underwent either DES or BMS implantation in large coronary vessels was followed for a mean duration of 4.5 years. Patients were divided into 4 subgroups by the reference vessel diameters (Q1: 3.0-3.25 mm, Q2: 3.26-3.50 mm, Q3: 3.51-3.75 mm, and Q4: 3.76-4.50 mm). The primary endpoint was major adverse cardiac events (MACE), defined as a composite of cardiac death, myocardial infarction, target vessel revascularization, and stent thrombosis. The propensity score-adjusted Cox regression method was applied. Results In the 3 subgroups with smaller vessel sizes, the adjusted risk of MACE in DES recipients was reduced by 82% in Q1 (hazard ratio [HR]: 0.18, 95% confidence interval [CI]: 0.09-0.38), 49% in Q2 (HR: 0.51, 95% CI: 0.26-0.98), and 67% in Q3 (HR: 0.33, 95% CI: 0.15-0.73). However, in the largest vessel subgroup (> 3.75 mm), all clinical outcomes were not significantly different irrespective of the stent type used. Conclusions The incidence of MACE in 3.0-3.75 mm vessels was significantly reduced by the use of DES than by the use of BMS during a long-term follow-up. However, DES lost its benefit in > 3.75 mm vessels.