Safety of Sirolimus-Eluting Stenting and Its Effect on Restenosis in Patients With Unstable Angina Pectoris (a SIRIUS Substudy)

The SIRIUS study was a double-blinded, randomized trial of the sirolimus-eluting stent (SES) to evaluate its effect on the rate of restenosis. The present report is a retrospective analysis of short- and long-term outcomes of SESs compared with bare metal stents (BMSs) in a subgroup of patients with unstable angina enrolled in the trial. Of 1,058 patients randomized in SIRIUS, 533 (50.4%) had unstable angina pectoris and 490 had stable angina. In the unstable angina group, patients treated with SESs and BMSs had similar clinical and angiographic characteristics. The stenting procedure was highly successful in the 2 groups (95.9% and 97.4%, respectively) with similar immediate angiographic results and short-term (in-hospital) clinical event rates. At 1-year follow-up, compared with BMSs, patients with unstable angina treated with SESs had significantly lower rates of target lesion revascularization (5.5% vs 22.3%, p <0.0001), target vessel failure (10.9% vs 26.3%, p <0.0001), and major adverse cardiac events (8.4% vs 24.8%, p <0.0001). Stent thrombosis was a rare event, with only 1 patient (0.4%) in each group during the first 30 days. Late thrombosis occurred in 2 patients (0.7%) in the BMS group but in none of the SES group. In conclusion, in the higher risk subgroup of patients with unstable angina, SESs are as safe as BMSs in decreasing restenosis and the need for repeat revascularization. This is reflected by a significant decrease in major adverse cardiac events and target vessel failure. Patients with unstable angina undergoing percutaneous coronary intervention who meet the entry criteria of the SIRIUS study should be preferentially treated with SESs.