The evaluation of a small-diameter polysaccharide-based arterial graft in rats

Cardiovascular diseases may require surgery such as arterial bypasses that are usually performed with synthetic PTFE and Dacron grafts with diameter above 6 mm. For smaller diameter replacement, healthy vascular tissue from the patient is not always available to carry out this type of graft. The purpose of this study was to evaluate the effectiveness of a small-diameter polysaccharide-based scaffold as an alternative arterial replacement. Tubular polysaccharide-based grafts of 2 mm internal diameter were prepared and moulded by a cross-linking technique. Fifteen Wistar adult rats underwent infrarenal aortic bypass with these grafts using microsurgical techniques. Grafts withstood aortic blood pressure and exhibited physiological blood flow, as evaluated with ultrasound techniques and angiographies at 4 and 8 weeks post-surgery. Harvested grafts were morphologically evaluated by light microscopy and immunohistochemistry. Neointima formation at 8 weeks was evidenced through collagen deposition and smooth muscle-like cells circumferential growth on the luminal surface without intimal hyperplasia or aneurysm formation. In conclusion, we described a 2 mm polysaccharide-based arterial material being investigated in vivo and demonstrating patency for up to 8 weeks post-surgery with neointima formation and absence of intimal hyperplasia.