Comparison of neointimal hyperplasia and peri-stent vascular remodeling after implantation of everolimus-eluting versus sirolimus-eluting stents: Intravascular ultrasound results from the EXCELLENT study

This study was designed to compare neointimal hyperplasia and peri-stent arterial remodeling after implantation of everolimus-eluting stent (EES) versus sirolimuseluting stent (SES) using intravascular ultrasound (IVUS). The study population was a subgroup of 278 patients from the EXCELLENT trial, a randomized study comparing EES to SES in de novo coronary artery lesions (total n = 1,443, 3:1 randomization) who underwent post-PCI and 9-month follow-up IVUS evaluation. There were 209 patients in the EES group and 69 in the SES group. Baseline clinical and angiographic characteristics were similar between the two groups except for age and target lesion locations.At 9 months, percent neointimal volume obstruction did not differ between EES and SES (2.6 ± 4.0 % vs. 2.5 ± 4.8 %, p = 0.814). However, the relative change in the vessel (4.3 ± 13.7 % vs. 8.8 ± 18.6 %, p = 0.030) and plaque volume index (4.2 ± 17.4 % vs. 10.5 ± 22.3 %, p = 0.016) of the stented segment frompost-intervention to follow-upwas significantly less with EES than with SES. In addition, positive peri-stent vascular remodeling defined as an increase in vessel volume index[10 % (27.8 vs. 42.0 %, p = 0.027) and late acquired stent malapposition (LASM, 1.9 vs. 15.9 %, p<0.001) were observed less frequently with EES than SES. EES and SES were similarly effective in reducing neointimal hyperplasia. However, positive peri-stent vascular remodeling and LASM occurred less frequently with EES than SES.