Cardiac valvular replacement devices: residual problems and innovative investigative technologies.
The advancements in cardiac valvular replacement devices over the past 25 years have left residual problems with biological and mechanical prostheses. The extensive developments were introduced to reduce or eliminate valve-related complications, namely thromboembolism, anticoagulant-related hemorrhage, and structural failure, as weil as to optimize hemodynamic performance. Residual problems persist with both biological and mechanical prostheses. Structural failure of porcine and pericardial bioprostheses persists over time with leaflet degeneration and dystrophic calcification. Thrombus formation from blood stasis and the resultant thromboembolic phenomena despite anticoagulant management remain a continuing problem with mechanical prostheses. The innovative  echnologies under investigation will likely significantly improve the clinical performance of both biological and mechanical prostheses.
Jamieson
W R
WR
University Heart Centre, St. Paul s Hospital, Vancouver Hospital and Health Sciences Centre, Vancouver, Canada.
Lichtenstein
S V
SV