Randomized comparison of biodegradable polymer versus durable polymer sirolimus-eluting stenting in patients with acute ST-elevation myocardial infarction undergoing primary PCI

Abstract

Background: Sirolimus-eluting stents (SES) with biodegradable polymer coating showed promising results in registry studies. We investigated whether their efficacy and safety were noninferior to those of durable polymer-coated SES in primary percutaneous coronary intervention (PCI) for patients with acute ST-segment elevation myocardial infarction (STEMI). Methods: A total of 1192 STEMI patients within 12 hours of symptom-onset were randomly assigned, in an open-label fashion with 1:1 ratio, to receive SES coated with biodegradable (n=596) or durable polymer (n=596) during primary PCI. Primary endpoint was composite major adverse cardiac events (MACE) at one-year follow-up, including all-cause mortality, recurrent myocardial infarction, and target lesion revascularization. Secondary endpoint included individual components of primary endpoint and stent thrombosis according to the ARC definition. Results: Compared with durable polymer coated SES, the non-inferiority of SES with biodegradable polymer coating was established by an absolute risk difference of -0.9% in primary endpoint (12.4% vs. 13.3%, p=0.67) and an upper limit of one-sided 95% CI at 2.96% (one-sided p value for non-inferiority=0.001). And the finding of non-inferiority of SES with biodegradable polymer coating was consistent across the subgroups of patients with left ventricular dysfunction, door-to-balloon time 65 years in age. Despite similar occurrence of acute and subacute stent thrombosis (definite or probable), late stent thrombosis was lower after implantation of biodegradable polymer coated SES (0.7% vs. 2.2%, p=0.03). Conclusions: Our results indicate that a stent eluting sirolimus from a biodegradable polymer represents an effective and safer alternative to a stent eluting sirolimus from a durable polymer in STEMI patients treated by primary PCI.