Long-term clinical outcome in patients with small vessel disease treated with drug-eluting versus bare-metal stenting

Background: DES is superior to BMS in reducing restenosis and repeat revascularization. Available data are less convincing in small vessel disease. Aim of our study is to assess long-term clinical outcome of drug-eluting stents (DES) vs. bare-metal stents (BMS) in small coronary vessel disease.

Methods: Procedural and long-term clinical outcomes were assessed in consecutive patients (pts) treated with stenting of native small coronary arteries (reference vessel diameter and implanted stent < 3mm).

Results: Pts enrolled were 645: DES group (n = 277) presented more frequently diabetes (173 [62%] vs. 32 [9%], P < .0001), higher body mass index (27 ± 5 vs. 26 ± 4, P = .01) and with previous PCI (115 [42%] vs. 118 [32%], P = .01) as compared to BMS group (n=368). DES group presented more frequently with unstable angina (46 [17%] vs. 38 [10%], P = .02); BMS group presented more frequently with myocardial infarction (103 [28] vs. 43 [15], P = .0002). Reference vessel (2.27 ± 0.36 vs. 2.24 ± 0.36, P = .29), minimal lumen (0.81 ± 0.32 vs. 0.80 ± 0.31, P = .84) and stent diameter (2.59 ± 0.17 vs. 2.60 ± 0.15, P = .69) did not differ between the 2 groups. Lesion length was significantly higher in DES group (15.85 ± 6.81 vs. 13.66 ± 7.18, P = .01). At a median clinical follow-up of 3.0 years (IQR range 2.2-4.6), pts with DES showed significantly lower major adverse cardiac events (MACE, HR 0.51, 95%CI 0.33-0.78) and target vessel revascularization (TVR, HR 0.44, 95%CI 0.25-0.78). No differences were observed between the two groups as to death, myocardial infarction and stent thrombosis.

Conclusions: In small vessel disease, DES was more frequently implanted in pts at higher risk of restenosis, though it demonstrated to be more effective than BMS in reducing MACE and TVR at long-term follow-up.