Sirolimus-eluting stents for the treatment of bare-metal in-stent restenosis: long-term clinical follow up.

Background: Studies focusing on short- and mid-term follow up support the beneficial role of sirolimus-eluting stents (SES) in the treatment of in-stent restenosis (ISR), yet no long-term safety and/or efficacy data are available.

Methods: Patients with ISR following bare-metal stenting (BMS) and treated with SES were prospectively studied. Baseline, procedural, and in-hospital data were appraised. The primary endpoint was the rate of major cardiovascular events (MACE) at long-term follow up (>9 months). Secondary endpoints were the individual contributors to MACE.

Results: A total of 180 SES were implanted to treat 138 consecutive patients. Procedural success was achieved in all patients without in-hospital death, acute stent thrombosis, stroke, or urgent coronary artery bypass. During follow up, MACE occurred in 5.8% of patients at 6 months, 14.3% at 12 months, and 25% at 24 months. Specifically, all-cause mortality was 1.7% at 6 months, 3.5% at 12 months, and 4.8% at 24 months, for a total of 5 deaths. Target vessel revascularization occurred at 6, 12, and 24 months in 4.2%, 11.2%, and 15.9% of patients, respectively, while target lesion revascularization (TLR) alone accounted for 3.4% at 6 months, 9.6% at 12 months, and 11% at 24 months. Three case of myocardial infarction occurred during follow up (2.2%), without any surgical revascularization or stent thrombosis.

Conclusions: Treatment of ISR with SES appears safe and effective, even if a 10% annual rate of MACE can be expected, with a sizable portion of these due to apparently nontarget lesion events.