Effectiveness and safety of the sirolimus-eluting stents coated with bioabsorbable polymer coating in human coronary arteries

Background: Although the sirolimus-eluting stent (CYPHER (R), Cordis, USA) has shown a dramatic reduction of restenosis, there are still some concerns about its efficacy and safety. Its durable polymer coating may enhance neointimal proliferation and residual sirolimus, which cannot be released from polymer, may result in incomplete reendothelization. As a drug reservoir, bioabsorbable polymer (polylactic acid, PLA) is more rational. Objective: We aimed to determine the safety and efficacy of sirolimus-eluting stent coated with PLA (EXCEL (R), JW Medical Systems, China) in the treatment of human coronary arterial diseases. Methods: The study included 31 patients with de novo coronary lesions, with vessels 2.5-3.5 mm in diameter. The primary end points included the percentage of in-stent restenosis of the luminal diameter and in-stent late luminal loss at 6 months, as determined by quantitative angiography. The secondary end point was the major adverse cardiac events (MACE) 30 days and 6 months after the index procedure. Results: Forty-eight EXCEL stents were successfully delivered in the 34 lesions, and multiple stents were implanted in 35.3% of lesions. All patients were discharged without clinical complications and completed clinical follow-up at 1 and 6 months. No MACE had occurred. Twenty patients (30 stents) completed 6 months of angiographic follow-up. No in-stent or in-lesion restenosis (diameter stenosis >= 50%) was observed. In-stent late loss was (0.07 +/- 0.17) mm. Conclusions: The implantation of EXCEL stent is feasible and safe and elicits minimal neointimal proliferation. This new stent has potential advantages regarding the long-long-term result over the commercially stent as the new stent has no sustained stimulation to the local tissue. (c) 2006 Wiley-Liss, Inc.