Background: Diabetes has been reported as an independent predictor of restenosis after drug-eluting stent implantation. The purpose of this study was to assess the long-term impact of increased drug dose in sirolimus-eluting stents (SES) on neointimal hyperplasia (NIH) in diabetic patients using volumetric intravascular ultrasound analysis.
Methods: The 3D trial is a multicenter, prospective, randomized, feasibility study of double-dose (280 microg/cm2) or conventional single-dose (140 microg/cm2) SES for the treatment of de novo coronary lesions in diabetic patients. To evaluate long-term efficacy, complete serial volumetric analyses (baseline, 6-month and 2-year follow up) were performed in 39 diabetic patients (17 single-dose, 22 double-dose). Each volume was divided by stent length to acquire volume index, expressed as mm3/mm. Percent neointimal volume was calculated as (neointimal volume/stent volume) x 100 at follow up.
Results: Volumetric analysis showed similar results over time between the 2 stent groups (p = NS for all). At 2-year follow up, minimal increases in NIH area and percent NIH were observed in both groups, which translated into a decrease in lumen volume index compared to baseline (p < 0.05 for all). No late-acquired incomplete stent apposition was observed in either group.
Conclusions: The current single dose of sirolimus in SES is effective in inhibiting NIH in diabetic patients up to 2 years. In this patient subset, double-dose SES did not confer additional NIH suppression at 2-year follow up compared to conventional single-dose SES.