Experimental Implantation and Evaluation of Mitral Valves in Sheep
Hartker, Frederick W. (Rick)
MetadataShow full item record
With the development of cardiopulmonary bypass in 1960, cardiac valve replacement became the most popular method of treatment for severe cardiac valve disease. Since that time, valve replacement operations have become increasingly common and the number of replacement valve types has grown. Thus, it is quite important that the surgical techniques of implantation be perfected and that different valve types be tested to determine the most suitable replacement valve. During my study, we performed 28 mitral valve implantations on sheep. By making subtle changes in the conventional implant methodology we were able to reduce the amount of time our sheep were on cardiopulmonary bypass. After implantation, hemodynamic studies were done on implanted mechanical valves. These studies indicated that the Starr-Edwards valve (ball and cage type) offered the least flow resistance followed closely by the St. Jude Medical valve (bileaflet type). Demonstrating somewhat higher flow resistance was the Medtronic-Hall valve (tilting disk type). The remaining implanted valves were gluteraldehyde-preserved homografts. The hemodynamics of these valves were not tested since the main objective after these implantations was simply to revive the sheep so that these valves could be studied upon explant (some 6 months later).