Differences in vascular tissue response after stent implantation between biolimus-eluting and everolimus-eluting stents: a sub-study of the NEXT study.

NEXT [NOBORI biolimus-eluting stent (BES) versus XIENCE/PROMUS everolimus-eluting stent (EES) trial] was a multicenter, randomized, prospective trial that included 3235 patients with 8-12 months of follow-up imaging at 18 centers. IB-IVUS images were analyzed at an interval of 0.5 mm using a motorized pull-back system in each plaque that required stent implantation. We analyzed seven cross-sections at the site of minimal lumen area and ten cross-sections in proximal and distal peripheral sites prior to the procedure, after stent implantation and after 8 months. We averaged the relative blue volume, relative green volume, relative yellow volume, and relative red volume across seven cross-sections using the manufacturer's default setting. Fifty-four lesions in 50 patients were analyzed. There were 28 lesions in 25 patients in the EES group and 26 lesions in 25 patients in the BES group. The patient characteristics did not differ significantly between the two groups except high-density lipoprotein cholesterol. There were no significant differences before and after stent implantation after 8 months in relative red volume, relative yellow volume, relative green volume or relative blue volume. Although the present study was likely underpowered for statistical analyses and larger populations are needed to confirm the conclusions, the vascular response regarding tissue characterization was similar between EES and BES, even though the thickness and releasing materials differed between the stents.