A long term comparison between Denacol® EX-313-treated bovine jugular vein graft and ultrafine polyester fiber graft for reconstruction of right ventricular outflow tract in dogs

Abstract

A Denacol EX-313 (Denacol)-treated bovine venous graft and an ultrafine polyester fiber (UFPF) graft were transplanted as patch graft into the right ventricular outflow tract under extracorporeal circulation in six dogs each experimentally. Hemodynamics in right heart and histological findings around the graft were compared between both groups over a period of one year after grafting. Pressure measurements and angiocardiography were performed through a cardiac catheter. Right ventricular pressure, pulmonary artery pessure, and right ventricle to pulmonary artery gradient were within normal limits in both groups at 1, 2, 3, 4, 6, and 12 months or more after grafting. No difference were seen between the values for the Denacol and the UFPF group. Histologically, the medial surface at the site of grafting was covered with vascular endothelial cells at one month after grafting in both groups. The density of the vascular endothelial cells increased with time after grafting, showing no clear difference between the two groups. Subendothelial layers comprised of collagen fibers, elastic fibers, and inflammatory cells decreased with time in both groups, but there was less cell infiltration in the Denacol group than in the UFPF group at all time points after grafting. In addition, the central cut thickness value of the graft tended to be thinner in the Denacol group than in the UFPF group at all observation time points after grafting. In the Denacol group, very slight metaplasia of cartilage was noted in a portion of the graft margin at six months or more after grafting, but no other abnormalities were observed. These results suggest that the Denacol-treated bovine venous graft has better grafting characteristics than the UFPF graft with easier intra-operative handlings and less tissue reactions after grafting.