Randomized comparison of early inflammatory response after sirolimus-eluting stent vs bare metal stent implantation in native coronary lesions

Abstract

Background The clinical significance of early inflammatory response after coronary stent implantation has been controversial. Sirolimus-eluting stent (SES) has been shown to be better outcomes compared with bare metal stent (BMS). We prospectively investigated the early inflammatory response after SES or BMS implantation in patients with single-vessel lesion, and evaluated the relationship between inflammation and late clinical outcomes in a randomized design. Methods Forty-eight patients with single-vessel disease were randomized into SES or BMS implantation group ( n = 24 respectively). Blood samples were taken before stenting, 1 h, 24 h and 8 months afterward. The plasma concentrations of C-reactive protein (CRP) and interleukin-6 (IL-6) were determined by ELISA. The clinical and angiographic follow-up were performed at 8 months after stenting. Results There was no difference in baseline characteristics, plasma CRP and IL-6 concentrations between the 2 groups. However, plasma IL-6 concentrations at 1 h after stenting were higher in both groups than in baseline ( p < 0.01). In addition, the plasma CRP and IL-6 concentrations at 24 h after stenting were significantly higher in both groups compared with baseline ( p < 0.01 respectively). Likewise, plasma CRP and IL-6 concentrations were significantly higher in BMS group compared with SES group at 24 h after stenting ( p < 0.05 respectively). At the follow-up (mean 8 months after stenting), the rate of in-stent restenosis (ISR) and target lesion revascularization (TLR) were higher in BMS group than in SES group ( p < 0.05 respectively) although the plasma CRP and IL-6 concentrations are similar between the groups. Conclusions Single coronary stenting could trigger an early inflammatory response. However, patients undergoing SES implantation has less augmentation of early inflammatory markers after stenting compared to patients treated with BMS, which was positively related the incidence of ISR and TLR at follow-up. This may reflect the potential impact of SES implantation on the early inflammatory response and late clinical outcomes.