Short-term effects of double-layer autologous vein graft on restraint of excessive distension and alleviation of neointimal hyperplasia in a porcine saphenous vein graft model

Abstract

Although the use of external vein graft support seems a promising approach to prevent neointimal hyperplasia and wall thickening in vein grafts, its extensive clinical application still has a long way to go. The aim of this study was to evaluate short-term effects of self-designed double-layer autologous saphenous vein graft on restraining excessive distension of vein graft and alleviating neointimal hyperplasia in a porcine model. Left and right hind femoral arteries of 24 white pigs were randomly divided into an experimental group (double-layer vein graft) and a control group (single-layer vein graft). After 1 h of implantation, then 1, 2, and 4 weeks later, the mean inner diameter of the vein grafts in the experimental group measured by Doppler-ultrasound was 2.7 ± 0.1, 2.8 ± 0.1, 2.9 ± 0.1, and 3.1 ± 0.1 mm, respectively; mean peak blood flow velocity measured by Doppler-ultrasound was 96.7 ± 12.8, 93.7 ± 11.5, 89.4 ± 9.6 and 84.6 ± 10.1 cm/s, respectively, while the mean neointimal thicknesses were 47.1 ± 7.7, 93.7 ± 15.1, and 177.4 ± 25.5 μm at 1, 2 and 4 weeks, respectively. As compared to the control group, inner diameter and neointimal thickness of vein grafts in the experimental group were significantly lower, while mean peak blood flow velocity was significantly higher at 1, 2, and 4 weeks after implantation. The proliferation index in the experimental group was also significantly lower within 4 weeks after implantation. The self-designed double-layer autologous saphenous vein graft restrains early excessive distension of vein graft and alleviates early neointimal hyperplasia.