Morphological assessment of the inflammatory response in the body of rats during implantation of vascular grafts

Objective. То investigate tissue reaction in animals after implantation of biological and synthetic vascular grafts.

Materials and methods. The study was carried out on male Wistar laboratory rats (n = 50). The animals were divided into 2 groups: group 1 — with implantation of a fragment of the biological vascular graft (25 animals), group 2 — with implantation of a fragment of a synthetic vascular graft made of Dacron (25 animals). Sampling for morphological examination was performed on the 3rd, 7th, 14th, 21st and 30th days after surgery.

Results. Animals with implanted fragment of a synthetic vascular graft, starting from the 3rd day after surgery, showed signs of fibrinous-purulent inflammation with the formation of purulent exudate on the 7th day, as well as signs of the beginning of the formation of granulation tissue around the graft. In the group of animals with implanted biological vascular graft, signs of maturing granulation tissue around the prosthesis with a large number of vessels and moderate inflammatory infiltration were revealed.

In animals with synthetic vascular graft, 3 weeks after surgery, classical macrophage giant cell granulomas surrounded by layers of collagen fibers were present in all the studied samples. Proliferating fibroblasts were found along the periphery of the inflammatory infiltrate in a group of animals with a biological vascular graft made of bovine xenopericardium.

On the 30th day, a fibrous capsule was formed in all animals with a fragment of a synthetic graft, and fibroblasts, connective tissue fibers and blood vessels were found in animals with implanted biograft.

Conclusion. There were no statistically significant morphological differences in the response of the rat organism to implantation of a biological vascular graft made of bovine xenopericardium compared with synthetic vascular graft made of Dacron coated with modified gelatin.

1. GBD 2019 Diseases and Injuries Collaborators. Global burden of 369 diseases and injuries in 204 countries and territories, 1990—2019: a systematic analysis for the Global Burden of Disease Study 2019. Lancet. 2020; 396 (10258): 1204—22.

2. Kazemzadeh G. H., Jirofti N., Mohebbi-Kalhori D. et al. Assessment of tissue reaction of rat to materials used in vascular grafts. Biomedical Research. 2018; 29 (13): 2194—6.

3. Faul F., Erdfelder E., Buchner A. et al. Statistical power analyses using G*Power 3.1: tests for correlation and regression analyses. Behav. Res. Methods. 2009; 41 (4): 1149—60.

4. State Standard 10993-6-2011 Medical devices. Assessment of the biological effect of medical devices. Part 6. Investigation of local action after implantation. Moscow: Standartinform Publ.; 2013. [(in Russian)]

5. Pinto Tde J., Saito T., Glerean A. Biocompatibilidade de materiais empregados na confec3ao de pryteses cardiovasculares: compara3ao entre peric6rdio bovine e Dacron. Rev. Saude Publica. 1993; 21(3): 185—9.

6. Chiba Y, Muraoka R., Ihaya A. et al. Postoperative inflammatory reactions of impregnated Dacron grafts. Surg. Today. 1999; 29(11): 1225—8.

7. Kohler R., Pohl C., Walschus U. et al. Association of systemic antibody response against polyethylene terephthalate with inflammatory serum cytokine profile following implantation of differently coated vascular prostheses in a rat animal model. J. Biomed. Mater. Res. A. 2022; 110 (1): 52—63.

8. Wang Z., Wang S., Marois Y. et al. Evaluation of biodegradable synthetic scaffold coated on arterial prostheses implanted in rat subcutaneous tissue. Biomaterials. 2005; 26 (35): 1381—401.

9. Drury J. K., Ashton T. R., Cunningham J. D. et al. Experimental and clinical experience with a gelatin impregnated Dacron prosthesis. Ann. Vasc. Surg. 1981; 1 (5): 542—1.