Experimental analysis of tensile force of individualized stents for microvascular anastomoses.

The aim of this project was to investigate the fundamental idea of the possibility of anastomosing small blood vessels in microvascular transplant procedures by an individualized stent known from coronary angioplasty. We investigated the influence of length, dilation and differences in fabrication of the newly developed balloon-expandable stent on the tensile force of stented anastomoses. Various gripping devices were tested and validated to investigate how the length, dilatation and differences in fabrication of the newly developed stent influence the tensile force of the stented anastomosis. Overall, 66 arteries of thiel-fixed human cadavers were investigated, divided into 11 groups. The median tensile force in sutured anastomoses was 2.96 N. The stented anastomoses with 24 mm stents and Ø 3.5 mm dilation attained approximately two-thirds of F(max)-values compared with conventional sutured anastomoses. If the stent was less dilated or had a shorter length, the maximum tensile force of the anastomosis was lower. Recent developments with an inversely oriented stent structure are expected to achieve even higher tensile force values. Further research in stent design to reduce leakage is necessary. A reduction of stent and catheter dimension is also needed to enhance the implantation method.