Biodegradable Polymer Versus Polymer-Free Ultrathin Sirolimus-Eluting Stents: Analysis of the Stent Arm Registry from the HOST-IDEA Randomized Trial

BACKGROUND: The efficacy and safety of each third-generation drug-eluting stent with ultrathin struts and advanced polymer technology remain unclear. We investigated the clinical outcomes of percutaneous coronary intervention using the Coroflex ISAR polymer-free sirolimus-eluting stent (SES) or Orsiro biodegradable polymer SES. METHODS: The HOST-IDEA trial (Harmonizing Optimal Strategy for Treatment of Coronary Artery Stenosis-Coronary Intervention With Next-Generation Drug-Eluting Stent Platforms and Abbreviated Dual Antiplatelet Therapy), initially designed with a 2×2 factorial approach, sought to randomize patients undergoing percutaneous coronary intervention based on dual antiplatelet therapy duration (3 versus 12 months) and stent type (Coroflex ISAR versus Orsiro). Despite randomizing 2013 patients for dual antiplatelet therapy duration, the stent arm transitioned to a registry format during the trial. Among these, 328 individuals (16.3%) were randomized for Coroflex ISAR or Orsiro SES, while 1685 (83.7%) underwent percutaneous coronary intervention without stent-type randomization. In this study, the Coroflex ISAR (n=559) and Orsiro groups (n=1449) were matched using a propensity score. The prespecified primary end point was target lesion failure, a composite of cardiac death, target vessel myocardial infarction, and clinically driven target lesion revascularization at 12 months. RESULTS: The baseline patient and procedural characteristics were well balanced between the Coroflex ISAR and Orsiro groups after propensity score matching (n=559, each group). The Coroflex ISAR group was significantly associated with a higher rate of target lesion failure, mainly driven by clinically driven target lesion revascularization, compared with the Orsiro group (3.4% versus 1.1%; hazard ratio, 3.21 [95% CI, 1.28-8.05]; P=0.01). A higher risk of target lesion failure in the Coroflex ISAR group was consistently observed across various subgroups. The rates of any bleeding (hazard ratio, 0.85 [95% CI, 0.51-1.40]; P=0.52) and major bleeding (hazard ratio, 1.58 [95% CI, 0.61-4.08]; P=0.34) were comparable between the 2 groups. CONCLUSIONS: In this propensity score-matched analysis of the stent arm registry from the HOST-IDEA trial, the Orsiro SES was associated with significantly better outcomes in terms of 1-year target lesion failure, mainly driven by clinically driven target lesion revascularization, than the Coroflex ISAR SES.