Characteristics of patients and types of lesions in patients with drug-eluting or bare-metal stent implantation in small coronary arteries: from the FU-Registry.

Although the use of drug-eluting stents (DES) has reduced the rate of restenosis, some problems remain regarding the usefulness of DES in small coronary arteries in addition to late thrombosis and a longer duration of dual-antiplatelet therapy. We considered 335 patients with 698 lesions who underwent DES or bare-metal stent (BMS) implantation, and randomly selected 172 DES and 124 BMS lesions that had undergone a complete data analysis and evaluation. Patients had a history of stable angina with at least 1 lesion with 50% diameter stenosis in a vessel and with a successfully minimum stent implantation (stent diameter=2.5mm). The baseline characteristics including the clinical presentation and cardiovascular risk factors were similar between the DES and BMS groups, except for the percentage of dyslipidemia (DL). Pre-procedure reference vessel diameter (RVD pre) in the DES group was significantly smaller than that in the BMS group (p<0.01), and stent length in the DES group was significantly longer (p<0.01). There was no significant difference in the cumulative incidence of major adverse cardiac events including the target lesion revascularization rate, whereas in-stent restenosis (ISR) in the DES group was significantly lower than that in the BMS group. In a multivariate analysis of ISR, diabetes mellitus, prior percutaneous coronary intervention, and DES use in clinical background were identified as independent predictors of ISR. In addition, RVD pre, stent length, and DES use in angiographical background were also identified. In conclusion, DES use is an independent predictor of ISR, although the DES group included more severely diseased small coronary arteries.