Aim. To study long-term results of sirolimus-eluting stent “Calypso” in patients with acute coronary syndrome. Methods. The study includes 274 patients with acute coronary syndrome who underwent percutaneous coronary revascularization with implantation either sirolimus-eluting stent “Calypso” (Angioline, Russia), n = 140, or everolimus-eluting stent “Xience Prime” (AbbottVascular, USA), n = 134. Their status was monitored by phone up to a 36-month's period. Patients who were diagnosed with or suspected of having myocardial ischemia underwent coronary angiography. Primary safety parameter major adverse cardiac events (MACE) was assessed as a composite of all-cause death, nonfatal myocardial infarction, and clinically indicated coronary revascularization. Efficacy analysis was performed as an incidence of repeat coronary angiography due to coronary artery disease progression or new ischemic events occurrence and the incidence of restenosis, defined as >50% lumen diameter reduction of previously stented target lesion. The incidence of late stent thrombosis was also assessed. Results. Major adverse cardiac events were observed in 13.6% of patients in “Calypso” group and in 14.2% of patients in “Xience Prime” group (р = 0.999; RR 0.96 [0.53; 1.72]). Coronary angiography due to recurrence or exacerbation of cardiac angina was performed in 85 (60.7%) and 77 (57.5%) patients, respectively. No case of late stent thrombosis was observed. Conclusion. Sirolimus-eluting coronary stent “Calypso” used in patients with acute coronary syndrome is effective and safe. Results of the trial can be used to recommend this stent in routine clinical practice for managing the patients with acute coronary syndrome. Copyright: © 2019 Cherniaev et al