Thrombogenic performance of a st. Jude bileaflet mechanical heart valve in a sheep model.

摘要: The sheep model is preferred for chronic evaluation of prosthetic heart valves, surgical techniques, and endocardiographic studies. A bileaflet mechanical valve (MHV) was implanted into a to study its in vivo performance evaluate the thrombogenic potential valve. Transesophageal echocardiography transcranial Doppler ultrasonography measurements were conducted before after implantation. Platelet activity state (PAS) assay also implantation surgery. After euthanasia, MHV explanted scanning electron microscopy (SEM) performed on examine changes surface. Tissue blocks taken from brain, left ventricle, aorta, spleen, lung lobes histological examination. Our results indicated that implantation, more embolic signals detected carotid artery, increasing monotonously as function time. Echocardiographic parameters including blood aortic velocity, transvalvular pressure gradient, velocity time integral increased. PAS increased significantly SEM pictures demonstrated calcium phosphate deposition surfaces. Histological examination hemorrhage tissue, pulmonary thrombosis, osteogenesis tissue. ASAIO Journal 2006; 52:28‐33.