The efficacy of drug eluting stents on restenosis reduction in small coronary arteries

Background and Objectives: The previous studies have demonstrated the superiority of implanting drug eluting stent (DES) for restenosis reduction compared with the implantation of uncoated stents in small coronary arteries. However, the arteries in those studies tended to have short lesions. So, we evaluated the efficacy of a drug eluting stent in small coronary lesions with a relatively long length. Subjects and Methods: From July 2003 to March 2005, DESs (Cypher or Taxus) were implanted into 100 consecutive patients with 116 lesions that were less than 2.75 mm in diameter. All patients received aspirin indefinitely and clopidogrel for 6 months. The primary end point was 6 month angiographic in-segment restenosis, and the secondary end points were procedural success and any major adverse cardiac events (MACE: death, non fatal myocardial infarction and target lesion revascularization) at 9 months. Results: The mean age of the patients was 63 years, 53% were male, 24% were diabetics, 34% were current smokers and 55% had hypertension. A total of 121 DESs were implanted into 116 lesions (mean number of DESs/lesion: 1.1/lesion). The mean proximal and distal reference diameters were 2.21 ± 0.39 and 2.01 ± 0.40 mm, respectively. The mean lesion length was 19.14 ± 7.89 mm. The mean pre- and post- minimal lumen diameters were 0.73 ± 0.42 mm and 2.26 ± 0.41 mm, respectively. The mean size and length of the stents were 2.65 ± 0.13 mm and 28.46 ± 10.04 mm, respectively. The procedural success rate was 98.3%. The angiographic follow-up rate was 78.4%. The binary in-segment restenosis rate was 15.4% (14 lesions). The MACE at 9 months was 8.0%. Conclusion: DES implantation in small coronary lesions with a relatively long length demonstrated favorable results. However, a larger scale study is needed to clarify the efficacy of the DES in small coronary arteries.