Malfunction of a Hancock bioprosthesis in the mitral position 24 years after initial implantation

Background and aims of the study: Although many types of cardiac bioprosthe tic valves are currently available, the major disadvantage of their use is limited durability due to progressive structural valve deterioration. Few s uch valves function beyond 20 years. Methods: A 61-year-old man was admitted urgently to our institute with acut e mitral insufficiency, 24 years after undergoing mitral valve replacement with a 25-mm standard Hancock porcine bioprosthesis for mitral stenosis. Results: Mitral valve reoperation was performed successfully with a mechani cal valve. The explanted bioprosthesis showed leaflet perforations and a co mmissural tear, moderate calcification on the commissures, and pannus overg rowth. Conclusion: The findings in this case suggest that individual patient varia bles, as well as the design and the construction of the valve are major det ermining factors in the rate of valve failure.