Baseline and 9 months IVUS analysis of the bifurcation‐dedicated biolimus A9‐eluting Axxess stent system: The DIVERGE IVUS substudy

Abstract

Percutaneous treatment of complex coronary bifurcation lesions remains challenging, even in the drug-eluting stent era. We sought to evaluate the baseline and 9 months intravascular ultrasound (IVUS) analysis of the Axxess™ stent, a self-expanding, Biolimus A9™-eluting, and dedicated bifurcation stent. We enrolled the first 76 patients from selected sites of the 302 patients large DIVERGE trial (a prospective, single-arm, multicenter trial evaluating the safety and efficacy of the Axxess stent). Both baseline and 9 months IVUS images were collected for serial two-dimensional (2D) and 3D analysis. A minimal amount and a low percentage of neointimal volume index were seen in the Axxess stent at 9 months (0.4 ± 0.6 mm(3) /mm and 4.3 ± 5.2%, respectively). Vessel, lumen, and stent volume indices increased significantly (respectively, 17.0 ± 3.6 to 18.9 ± 3.7 mm(3) /mm, P < 0.0001; 7.3 ± 2.0 to 9.2 ± 2.5 mm(3) /mm, P < 0.0001; and 7.4 ± 2.0 to 9.6 ± 2.6 mm(3) /mm, P < 0.0001). This resulted in minimum lumen area (MLA) enlargement (6.1 ± 1.9 to 7.2 ± 2.3 mm(2) , P < 0.0001), whereas peristent plaque area decreased (8.7 ± 2.5 to 8.5 ± 2.1 mm(3) /mm, P = 0.016). At 9 months, 16 (26%) incomplete stent apposition (ISA) persisted from baseline, while six resolved (9.7%). Only one (2%) ISA was late acquired. In the additional distal sirolimus-eluting stents, MLA decreased from 4.3 ± 1.1 to 4.1 ± 1.2 mm(2) (P = 0.04) at 9 months for the main branch, and from 3.4 ± 1.2 to 3.2 ± 1.2 mm(2) (P = 0.09) for the side branch. The dedicated bifurcation Axxess stent system demonstrates significant stent volume increase with minimal neointimal formation and a low incidence of late-acquired ISA at 9 months.