Preparation of valved aortic stent and in vitro implantation to aortic valve position through catheter / 第二军医大学学报

ABSTRACT

Objective: To evaluate the feasibility of implanting a new self-expanding valved stent for aortic valve implantation and its influence on coronary blood flow. Methods: We designed a self-expanding valved stent made from super-elastic memory nitinol alloy, with a tubular shape and a wide mesh in the cavate middle part. A valvular ring made of nitinol wire was sutured on the lower part. Fresh porcine pericardium was decellularized, treated with 0.6% glutaraldehyde solution for 36 h, trimmed into leaflets, and sutured by hand into the valvular ring. The valved stent was pulled into a 14-French sheath by a silk and positioned in the left ventricle of isolated pig heart via the ascending aorta, and then deployed over the native aortic valves by pulling back the outer sheath. Water was injected into the ascending aorta by a silicon tube to evaluate the competence of the prosthetic heart valves and its effect on coronary flow. Results: The prepared valved aortic stent could be stably positioned over the native valves and could be removed after deployment. The prosthetic heart valves showed a satisfactory function and had no influence on coronary flow and mitral valve motion. Conclusion: This self-expanding valved stent is well-designed and allows for aortic valve implantation over the native valves without interfering the coronary flow; it can be evaluated further in vivo.