Experimental evaluation of the dialdehyde starch preserved bovine internal mammary artery as a small diameter arterial substitute

Abstract

A canine femoral artery model was used for evaluation of a dialdehyde starch preserved bovine internal mammary artery (BIMA) (3 and 4 mm internal diameter) in comparison to a polytetrafluoroethylene (PTFE) graft. The study comprised three groups for a 2-hour (n = 7, 3 mm), 3-month (n = 10, 4 mm), and 6-month (n = 10, 4 mm) follow-up. The thrombogenicity of the grafts was measured after 2 hours and 3 months using chromium 51 labeled autologous platelets. In addition, compliance studies were done. To control the wall stability of the xenografts, the collagen content before implantation and after explantation was examined together with the diameter of the grafts. Healing characteristics were studied using appropriate histologic methods. The acute platelet adhesion rate (2 hours) of the BIMA graft was 181 +/- 69 x 10(4) platelets/mm2 as compared to 57 +/- 43 x 10(4) for PTFE (p less than 0.05, t-test). However, after 3 months the thrombogenicity of the biograft had decreased whereas the platelet count at the PTFE graft had increased (BIMA: 79 +/- 48 x 10(4); PTFE: 179 +/- 102 x 10(4), p less than 0.05). At implantation, the compliance of the BIMA graft was 0.028% +/- 0.009% per mmHg as compared to 0.06% +/- 0.0025% of the femoral artery. The PTFE graft was uncompliant (0.008 +/- 0.005). After 6 months, the compliance of the femoral artery had decreased to 0.039% +/- 0.013% per mmHg, which was now well matched to the nearly unchanged compliance of the biograft (0.0027 +/- 0.005).(ABSTRACT TRUNCATED AT 250 WORDS)