A three-dimensional intravascular ultrasound comparison between the new zotarolimus-eluting stent (ZoMaxx) and the non-drug-eluting TriMaxx stent.

BACKGROUND:Despite the effectiveness of sirolimus- and paclitaxel-eluting stents in reducing intimal hyperplasia (IH) and the need for repeat revascularization, concerns about their long-term safety have motivated the search for new drug-eluting stents (DES). Recently developed, the ZoMaxx stent combines a sirolimus-analogous agent (zotarolimus), featuring a phosphorycoline polymer and stainless steel and tantalum platform. We sought to assess the efficacy of this new DES in reducing IH. METHODS:A total of 40 patients were treated with the ZoMaxx stent and compared to 50 patients treated with its non-drug-eluting equivalent, the TriMaxx stent. Only single de novo lesions in native coronary vessels greater than or equal to 3.0 mm were enrolled. Serial quantitative coronary angiography and intravascular ultrasound (IVUS) images were obtained at baseline and 6- month follow up. All patients were clinically followed for 1 year. This analysis aimed to compare the percent of IH between the 2 stents. Secondarily, we assessed in-segment late loss, binary restenosis and major adverse cardiac events. RESULTS:Baseline patient and lesion characteristics were comparable between the 2 groups. At follow up, zotarolimus efficiently suppressed neointimal hyperplasia formation with a marked reduction in the percentage of stent obstruction by IVUS (4.6 +/- 3.6% vs. 31.2 +/- 16%; p < 0.0001). Almost 90% of the segments stented with ZoMaxx did not exhibit more than 10% of obstruction. After 1 year, 12 patients treated with the TriMaxx and 2 patients treated with the ZoMaxx presented in-segment binary restenosis (p = 0.03). CONCLUSIONS:In this initial experience, ZoMaxx proved to be clinically safe and superior to its non-drug-coated equivalent in reducing in-stent IH formation and restenosis.