November 18th, 2013

Replacement Versus Repair for Mitral Valve Regurgitation

Surgery is thought to be life-saving for people who have ischemic mitral regurgitation, but it is unknown whether surgical repair or surgical replacement of the mitral valve is the better procedure. Repair is thought to result in fewer preoperative deaths and replacement is thought to have better long-term outcomes with a reduced incidence of recurrent mitral regurgitation. In recent years, many surgeons have grown to favor repair.

In a trial presented at the American Heart Association meeting in Dallas and published simultaneously in the New England Journal of Medicine, members of the Cardiothoracic Surgical Trials Network randomized 251 patients with severe ischemic mitral regurgitation to either repair or replacement.

At one year there was no difference in the primary end point, left ventricular end-systolic volume index, between the two groups. The mean change from baseline was -6.6 per square meter of body-surface area in the repair group and -6.8 in the replacement group. Mortality was not significantly different, either: 14.3% in the repair group versus 17.6% in the replacement group (HR 0.79, CI 0.42-1.47, p=0.45). However, moderate or severe recurrence of mitral regurgitation occurred significantly more often in the repair group: 32.6% versus 2.3% (p<0.001).

The authors wrote that their “findings contradict much of the published literature on this topic, which reports several advantages to mitral-valve repair over replacement, including lower operative mortality, improved left ventricular function, and higher rates of long-term survival.” One partial explanation may be that “evolution of valve replacement with chordal sparing may account for the improved results.”


2 Responses to “Replacement Versus Repair for Mitral Valve Regurgitation”

  1. David Powell , MD, FACC says:

    There are studies (though not large and randomized) suggesting that a subset of functionally regurgitant mitral valves are more likely to develop postoperative regurgitation. The degree of leaflet tethering (“tenting”) correlates with recurrent post-repair regurgitation. An annuloplasty incompletely addresses tethering. The substantial recurrence of MR in the repair group will likely lead to adverse remodeling and clinical decline in future years. Perhaps the authors studied the impact of mitral apparatus geometry .

  2. Thierry Legendre, MD says:

    Anyway, the great advantage of mitral repair over mechanical mitral replacement is the possibility not to take indefinite AVK treatment as long as sinus rhythm is maintained.
    Biological valve replacement pertains a risk of failure at least as high as mitral repair.