Introduction of a New ex vivo Porcine Coronary Artery Model: Evaluation of the Direct Vascular Injury after Stent Implantation with and without Dogbone Effect

Abstract

Introduction: Neointimal hyperplasia after percutaneous coronary intervention remains a major determinant of in-stent restenosis (ISR). The extent of mechanical vessel injury correlates with ISR. A new ex vivo porcine stent model was introduced and evaluated comparing different stent designs.

Methods: Coronary arteries were prepared from pig hearts from the slaughterhouse and used for ex vivo implantations of coronary stents. One basic stent design in two configurations (dogbone, DB; nondogbone, NDB) was used. Vascular injury was determined according to a modified injury score (IS).

Results: Standardized experimental conditions ensured comparable vessel dimensions and overstretch data. DB stents caused more severe IS compared to NDB stents. The mean IS and the IS at the distal end of all stents were significantly reduced for NDB stents (ISMean, DB, 1.16 ± 0.12; NDB, 1.02 ± 0.12; p = 0.018; ISDist, DB, 1.39 ± 0.28; NDB, 1.13 ± 0.24; p = 0.03).

Discussion/conclusion: The introduced ex vivo model allowed the evaluation of different stent designs, which exclude unfavorable stent designs.

Keywords: Ex vivo porcine stent model; Injury score; Stent design; Stent screening.