Subcoronary Implantation of Decellularized Aortic Allografts-An Ex Vivo and In Vivo Feasibility Study.

Background: Decellularized aortic homografts were introduced in 2008 as a further option for pediatric aortic valve replacement. Subcoronary decellularized aortic homograft implantation may eliminate the need for aortic root replacement and coronary artery reimplantation in patients with sufficient left ventricular outflow tract dimensions. Methods: Ovine aortic xenografts were harvested from the slaughterhouse and decellularized using an approved detergent-based decellularization protocol. Two cardiac surgeons performed subcoronary implantation in explanted ovine hearts, and results were compared regarding procedure time and procedural success. After these ex vivo experiments, 4 adult black-headed sheep were operated on in acute experiments. Results: The 2 surgeons were able to perform the ex vivo subcoronary implantation of the decellularized ovine aortic allografts (DOAA) without technical problems within 1 hour. Mechanical strength of the processed ovine DOAA appeared comparable to that of native aortic tissue. Both surgeons stated that there were no differences with respect to appearance, haptics, trimability, and sewability. The initial 2 sheep operated on showed significant valvular incompetence. After modification of the surgical protocol to a single-line suture technique, the next 2 sheep showed fully competent aortic valves with laminar flow across the subcoronary implanted DOAA. Conclusions: We have developed a technique for subcoronary implantation of decellularized aortic homografts including acute large animal experiments. Long-term animal experiments will provide further insight into durability and recellularization.