BACKGROUNDDrug eluting stents (DESs) made with biodegradable polymer have been developed in an attempt to improve clinical outcomes. However, the impact of biodegradable polymers on clinical events and stent thrombosis (ST) remains controversial.

METHODSWe searched Medline, the Cochrane Library and other internet sources, without language or date restrictions for articles comparing clinical outcomes between biodegradable polymer DES and durable polymer DES. Safety endpoints were ST (definite, definite/probable), mortality, and myocardial infarction (MI). Efficacy endpoints were major adverse cardiac event (MACE) and target lesion revascularization (TLR).

RESULTSWe identified 15 randomized controlled trials (n = 17 068) with a weighted mean follow-up of 20.6 months. There was no statistical difference in the incidence of definite/probable ST between durable polymer- and biodegradable polymer- DES; relative risk (RR) 0.83; 95% confidence interval (CI) 0.62-1.11; P = 0.22. Biodegradable polymer DES had similar rates of definite ST (RR 0.94, 95% CI 0.66-1.33, P = 0.72), mortality (RR 0.94, 95% CI 0.82-1.09, P = 0.43), MI (RR 1.08, 95% CI 0.92-1.26. P = 0.35), MACE (RR 0.99, 95% CI 0.91-1.09, P = 0.85), and TLR (RR, 0.94, 95% CI 0.83-1.06, P = 0.30) compared with durable polymer DES. Based on the stratified analysis of the included trials, the treatment effect on definite ST was different at different follow-up times: ≤ 1 year favoring durable polymer DES and >1 year favoring biodegradable polymer DES.

CONCLUSIONSBiodegradable polymer DES has similar safety and efficacy for treating patients with coronary artery disease compared with durable polymer DES. Further data with longer term follow-up are warranted to confirm the potential benefits of biodegradable polymer DES.

Coronary Artery Disease ; drug therapy ; surgery ; Drug-Eluting Stents ; Humans ; Polymers ; administration & dosage ; Thrombosis

BACKGROUNDFirst generation drug-eluting stents (DES) were associated with a high incidence of late stent thrombosis (ST), mainly due to delayed healing and re-endothelization by the durable polymer coating. This study sought to assess the safety and efficacy of the Nano polymer-free sirolimus-eluting stent (SES) in the treatment of patients with de novo coronary artery lesions.

METHODSThe Nano trial is the first randomized trial designed to compare the safety and efficacy of the Nano polymer-free SES and Partner durable-polymer SES (Lepu Medical Technology, Beijing, China) in the treatment of patients with de novo native coronary lesions. The primary endpoint was in-stent late lumen loss (LLL) at 9-month follow-up. The secondary endpoint was major adverse cardiac events (MACE), a composite of cardiac death, myocardial infarction or target lesion revascularization.

RESULTSA total of 291 patients (Nano group: n = 143, Partner group: n = 148) were enrolled in this trial from 19 Chinese centers. The Nano polymer-free SES was non-inferior to the Partner durable-polymer DES at the primary endpoint of 9 months (P < 0.001). The 9-month in-segment LLL of the polymer-free Nano SES was comparable to the Partner SES (0.34 ± 0.42) mm vs. (0.30 ± 0.48) mm, P = 0.21). The incidence of MACE in the Nano group were 7.6% compared to the Partner group of 5.9% (P = 0.75) at 2 years follow-up. The frequency of cardiac death and stent thrombosis was low for both Nano and Partner SES (0.8% vs. 0.7%, 0.8% vs. 1.5%, both P = 1.00).

CONCLUSIONSIn this multicenter randomized Nano trial, the Nano polymer-free SES showed similar safety and efficacy compared with the Partner SES in the treatment of patients with de novo coronary artery lesions. Trials in patients with complex lesions and longer term follow-up are necessary to confirm the clinical performance of this novel Nano polymer-free SES.

Aged ; Coronary Artery Disease ; drug therapy ; surgery ; Drug-Eluting Stents ; Female ; Humans ; Immunosuppressive Agents ; therapeutic use ; Male ; Middle Aged ; Prospective Studies ; Sirolimus ; therapeutic use