Comparison of zotarolimus-eluting stents with sirolimus-eluting and paclitaxel-eluting stents: intimal hyperplasia and vascular changes assessed by volumetric intravascular ultrasound analysis.

BACKGROUND As a substudy of the large, randomized ZEST (Comparison of the Efficacy and Safety of Zotarolimus-Eluting Stent with Sirolimus-Eluting and PacliTaxel-Eluting Stent for Coronary Lesions) trial comparing first- and second-generation drug-eluting stents, we evaluated intimal hyperplasia (IH) and vascular changes using volumetric intravascular ultrasound analysis. METHODS AND RESULTS Complete angiographic and volumetric intravascular ultrasound data immediately after stenting and at 9-month follow-up were available in 162 patients with 183 lesions: 61 sirolimus-eluting stents (SES), 64 paclitaxel-eluting stents (PES), and 58 zotarolimus-eluting stents (ZES). External elastic membrane, stent, lumen, and peristent plaque volumes (external elastic membrane minus stent) were normalized by stent length. Percent IH volumes were calculated as [IH volume/stent volume]×100, %. Reduction of minimal luminal area) was greater in PES than SES (-1.4±1.5 mm(2) versus -0.7±0.9 mm(2), P=0.003), whereas minimal luminal area change in ZES was not significantly different from SES (-1.2±1.0 mm(2) versus -0.7±0.9 mm(2), P=0.055). Percent IH volume was less in SES compared with PES (9.8±6.0% versus 17.5±11.2%, P=0.002) or with ZES (9.8±6.0% versus 18.2±7.6%, P=0.005). Comparing ZES versus PES, there were no significant differences in %IH volume (17.5±11.2% versus 18.2±7.6%, P=0.779) or changes in normalized lumen volume (-1.2±1.3 mm(2) versus -1.1±0.8 mm(2), P=0.452). Late stent malapposition was identified in 8 (13%) SES and 2 (3%) PES but in no ZES (P=0.050). Angiographic restenosis was detected in 6 lesions (3 PES and 3 ZES). CONCLUSIONS The degree of neointimal growth in ZES was similar to that in PES but less than that in SES. ZES had no late stent malappositions. CLINICAL TRIAL REGISTRATION URL: http://www.clinicaltrials.gov. Unique identifier: NCT00418067.