Abstract
AIMS: The purpose of this study was to compare the long-term outcomes of a biodegradable polymer, sirolimus-eluting stent (Orsiro) with a durable polymer, sirolimus-eluting stent (CYPHER) to determine if late failure of the CYPHER is caused by the polymer or sirolimus. METHODS AND RESULTS: A total of 447 patients who underwent percutaneous coronary intervention (PCI) with one of the study stents were retrospectively analysed. The composite of cardiac death, stent thrombosis, and clinically driven target lesion revascularisation (TLR) within two years after PCI occurred in 3.0% of the Orsiro group and 9.6% of the CYPHER group. Multivariable Cox regression results indicated that the Orsiro stent was a significant independent predictor of a lower occurrence of the composite outcome (adjusted HR 0.37, 95% CI: 0.14-0.87), stent thrombosis (adjusted HR 0.07, 95% CI: 0.00-0.65), clinically driven TLR (adjusted HR 0.26, 95% CI: 0.09-0.69), and stent failure (adjusted HR 0.26, 95% CI: 0.09-0.69) within two years after PCI. CONCLUSIONS: This study has demonstrated that late CYPHER failure is attributable more to its durable polymer than to the antiproliferative drug, sirolimus. This suggests that sirolimus-based, new-generation drug-eluting stents are relatively safe and are expected to show long-term outcomes superior to those of the CYPHER.