EVOLUTION OF THE SURGICAL APPROACH FOR REPLACEMENT OF DEGENERATED MITRAL BIOPROSTHESES

Background. Primary tissue failure is the most frequent indication for reoperation in patients with a mitral bioprosthetic valve (MBPV). Com plete excision of the bioprosthesis is time-consuming and may be compl icated by cardiac rupture at the atrioventricular junction or the post erior left ventricular wall where a strut is embedded, injury to the c ircumflex coronary artery, or late perivalvular leak., A new approach to avoid these complications by excision of only the bioprosthetic tis sue and attachment of a St. Jude value (SJV) to the intact stent has b een developed and evaluated. Methods. The results of replacement of fa iled MBPV with SJV in 71 consecutive patients between September 1992 a nd December 1994 were analyzed; 57 patients had the value replaced aft er complete excision and 14 with stent preservation. The demographic a nd clinical: profiles of the two groups were similar. Results. Among p atients undergoing complete excision of the MBPV, operative mortality was 14% (8 of 57) with 12 late deaths and a 5-year survival of 75% and three late perivalvular dehiscences requiring another operation. No o perative deaths occurred in the intact stent group and one late death (cancer), and all the remaining patients are doing well without periva lvular leaks or other complications. Conclusions. Leaving the MBPV ste nt intact eliminates the need for extensive dissection, thus shortenin g and simplifying the procedure and diminishing its attendant mortalit y and morbidity. It offers a safe and logical approach to replacement of a degenerated MBPV with a SJV of comparable size.