MORPHOLOGICAL EVALUATION OF THE NEOINTIMA AND VASA VASORUM FORMATION AFTER ABDOMINAL AORTIC REPLACEMENT IN AN EXPERIMENT

Background. The article considers one of the most important problems in modern vascular surgery – the choice of a vascular graft for performing reconstructive surgical operations on the great vessels. The aim of this study is to perform a morphological comparison of the neointima and vasa vasorum formation in an experiment using various types of vascular grafts. Material and methods. The study was performed on female white pigs (n=12). The animals were divided into 2 groups: group 1 – those with implantation of a synthetic vascular graft made of Dacron coated with modified gelatin, group 2 – those with implantation of a biological vascular graft made of bovine xenopericardium. The material for histological examination was explanted vascular grafts with segments of the abdominal aorta. The sections were stained with hematoxylin and eosin, and Masson trichrome. For the morphometric study we used digital images of histological preparations obtained from a Leica DFC425 digital camera as well as scanned digital images of histological preparations obtained from a Leica Aperio AT2 scanner. Results. Morphometric examination of the neointima revealed that 3 and 6 months after surgery, the thickness of the neointima when using a synthetic vascular graft was significantly greater than when using a biological vascular graft from bovine xenopericardium (p<0.001). Endothelization of the neointima was noted only in the group of animals with a bioprosthesis. At the same time, an earlier and more pronounced formation of vasa vasorum was noted in animals with an implanted biological vascular graft. Conclusion. The formation of neointima was noted when using both biological and synthetic vascular grafts. In the group of animals with an implanted biological vascular graft from bovine xenopericardium, neointima endothelization and pronounced vascularization were noted, which indicates a greater physiological potential of this graft and is a factor reducing the risk of thrombosis.