A modular branched stent-graft system for sutureless anastomoses in extensive aortic arch replacement - A porcine study

Background: We developed a modular branched stent-graft system to test whether it is feasible for sutureless anastomoses in extensive aortic arch replacement. Methods: Extensive aortic arch replacement was performed using the three-branched stent-graft system in eight pigs. Under deep hypothermic circulatory arrest, sutureless anastomoses were established at the distal aortic arch and the two supra-aortic arteries with the modular branched stent-graft system. External bandings on the distal arches were applied in six pigs (banding group) and not applied in two pigs (control group). No external banding was applied on the two supra-aortic arteries. Results: Successful procedures were achieved in all pigs in the banding group, whereas failures were seen in the control group owing to leakage from the distal arch anastomoses. The anastomosis at each distal aortic arch was completed in 10 minutes in the banding group and in 5 minutes in the control group; the anastomosis of each supra-aortic artery was achieved in 5 minutes. Median durations of the circulatory arrest, aortic cross-clamping, and cardiopulmonary bypass were 30, 67, and 174 minutes, respectively. The postoperative computed tomography revealed adequate alignment of the stents and appropriate size matching between stent-graft and native aorta. Histological examinations revealed no pressure necrosis at the sutureless anastomotic sites. Conclusions: This study confirmed the technical feasibility of sutureless anastomoses with the modular branched stent-graft system in porcine extensive aortic arch replacement. An external banding is essential for the secure hemostasis of the distal arch anastomosis, but it is not required for the supra-aortic arteries.