Comparison of Efficacy and Safety between First and Second Generation Drug-eluting Stents in Patients with Stable Coronary Artery Disease: A Single-center Retrospective Study

Abstract

Background: Lots of trials demonstrate that second-generation drug-eluting stents (G2-DES), with their improved properties, offer significantly superior efficacy and safety profiles compared to first generation DES (G1-DES) for patients with coronary artery disease (CAD) receiving percutaneous coronary intervention (PCI). This study aimed to verify the advantage of G2-DES over G1-DES in Chinese patients with stable CAD (SCAD).

Methods: For this retrospective observational analysis, 2709 SCAD patients with either G1-DES (n = 863) or G2-DES (n = 1846) were enrolled consecutively throughout 2013. Propensity score matching (PSM) was applied to control differing baseline factors. Two-year outcomes, including major adverse coronary events as well as individual events, including target vessel-related myocardial infarction, target lesion revascularization (TLR), target vessel revascularization, and cardiogenic death were evaluated.

Results: The incidence of revascularization between G1- and G2-DES showed a trend of significant difference with a threshold P - value (8.6% vs. 6.7%, χ2 = 2.995, P = 0.084). G2-DES significantly improved TLR-free survival compared to G1-DES (96.6% vs. 97.9%, P = 0.049) and revascularization-free survival curve showed a trend of improvement of G2-DES (92.0% vs. 93.8%, P = 0.082). These differences diminished after PSM. Multivariate Cox proportional hazard regression analysis showed a trend for G1-associated increase in revascularization (hazard ratio: 1.28, 95% confidence interval: 0.95-1.72, P = 0.099) while no significance was found after PSM. Other endpoints showed no significant differences after multivariate adjustment regardless of PSM.

Conclusions: G1-DES showed the same safety as G2-DES in this large Chinese cohort of real-world patients. However, G2-DES improved TLR-free survival of SCAD patients 2 years after PCI. The advantage was influenced by baseline clinical factors. G1-DES was associated with a trend of increase in revascularization risk and was not an independent predictor of worse medium-term prognosis compared with G2-DES.

Figure 1

The flowchart of this study. CAD: Coronary artery disease. PCI: Percutaneous coronary intervention. PTCA: Percutaneous transluminal coronary angioplasty. DES: Drug-eluting stents.

Figure 2

Kaplan–Meier curve analysis before propensity score matching for 2-year follow-up of all-cause death (a), MI (b), revascularization (c), MACE (d), TV-MI (e), TVR (f), TLR (g), cardiogenic death (h), and ST (i). G2-DES significantly improved TLR-free survival compared to G1-DES, and also a trend for G1-associated increase in revascularization. There is a separative trend in MACE-free survival and TVR-free survival. G2-DES: Second-generation drug-eluting stents; G1-DES: First-generation drug-eluting stents; PSM: Propensity score matching; MI: Myocardial infarction; MACE: Major adverse cardiovascular event; TV-MI: Target vessel-related myocardial infarction; TLR: Target lesion revascularization; TVR: Target vessel revascularization; ST: Stent thrombosis.

Figure 3

Kaplan–Meier curve analysis after propensity score matching for 2-year follow-up of all-cause death (a), MI (b), revascularization (c), MACE (d), TV-MI (e), TVR (f), TLR (g), cardiogenic death (h), and ST (i). Although no significant differences were found in all endpoints, there is a separative trend in MACE-free survival, revascularization-free survival, TVR-free survival and TLR-free survival curves after PSM. PSM: Propensity score matching; MI: Myocardial infarction; MACE: Major adverse cardiovascular event; TV-MI: Target vessel-related myocardial infarction; TLR: Target lesion revascularization; TVR: Target vessel revascularization; ST: Stent thrombosis.