Examination of Operatively-Excised Bioprostheses in the Mitral Valve Position to Determine the Reason for Dysfunction

Analysis of Dysfunctioning Mechanical Prostheses Excised from the Mitral Valve Position

Described herein are findings in 16 patients who had their dysfunctioning mechanical prostheses in the mitral valve position replaced. The mechanical prostheses had been in place from 2 to 157 months (mean 80). All but 1 patient had the mechanical prosthesis excised because of prosthetic stenosis or regurgitation or both secondary to prosthetic thrombus (despite warfarin therapy) on cloth-ring "pannus" overlaying the orifice or parabasilar detachment ("leak"). The dysfunction was the result of non-infected causes in 13 patients and to infective causes in 3. Three patients (19%) died in the early post-operative period; the other 13 patients survived >1 year. The prostheses were excised in a variety of methods by the explanting surgeons. The best procedure to excise the mechanical prosthesis appears to be mainly operator dependent.