OBJECTIVES: TheÂ ResoluteÂ zotarolimus-elutingÂ stentÂ (ZES-R) has a thinnerÂ stentÂ strut with biocompatible polymer than first generation drug-elutingÂ stents. However, minimalÂ opticalÂ coherencetomography (OCT) data exists about vascular responsesÂ afterÂ ZES-RÂ implantation.
METHODS: This study investigated OCT findings in ZES-RÂ implantationÂ and compared them to those inÂ sirolimus-elutingÂ stentÂ (SES)Â implantation. A total of 123 lesions (43 ZES-R and 80 SES) in 111 patients were evaluated with OCT atÂ 9Â monthsÂ afterÂ stentÂ implantation. Strut apposition,Â neointimalhyperplasia (NIH) thickness, andÂ stentÂ coverageÂ on eachÂ stentÂ strut were evaluated.
RESULTS: Mean NIH thickness was significantly greater in ZES-R-treated lesions than in SES-treated lesions (166Â Â±Â 73Â Î¼m vs. 96Â Â±Â 63Â Î¼m, respectively, PÂ <Â 0.001). The percentage of uncovered strut was significantly lower in ZES-R-treated lesions than in SES-treated lesions (4.4Â Â±Â 4.8% vs. 10.3Â Â±Â 13.2%, respectively, PÂ =Â 0.05). The percentage of malapposed struts was also significantly lower in ZES-R-treated than in SES-treated lesions (0.1Â Â±Â 0.4% vs. 1.5Â Â±Â 4.2%, respectively, PÂ =Â 0.002). Intracoronary thrombus was less frequently detected in ZES-R-treated lesions (4.7% vs. 30.0%, respectively, PÂ =Â 0.001).
CONCLUSIONS: ZES-R showed a lower incidence of uncovered or malapposedÂ stentÂ struts and intracoronary thrombus than SES atÂ 9-month follow-up OCT examination. Compared with SES, ZES-R may elicit more favorable vascular responses at the expense of an increasedÂ neointimalÂ proliferation.