Histology and Mechanics of In Vivo Tissue-Engineered Vascular Graft for Children.

Abstract Purpose To evaluate histological and mechanical properties of autologous in vivo tissue-engineered vascular grafts (in vivo-TEVGs) used for pediatric heart surgery. Description Molds of in vivo-TEVGs made of silicone drain tubes were embedded into the subcutaneous spaces in two boys during their first surgery and used as patch materials to treat pulmonary artery stenosis during the second surgery. The remaining pieces of the patches were evaluated histologically and mechanically. Evaluation In vivo-TEVGs had very smooth luminal surfaces, their walls mainly comprised collagen fibers and small numbers of fibroblasts. The mean wall thickness was 200 μm, mean suture retention strength was 2.26 N, and burst pressure was 3057 mmHg. Conclusions Human in vivo-TEVGs mainly comprise collagen fibers and their mechanical properties prove them safe for pulmonary arterioplasty. Therefore, human in vivo-TEVGs may be promising alternatives to autologous pericardium for pediatric cardiovascular surgeries that often require multi-stage operations.