Update on surgical repair in functional mitral valve regurgitation.
Abstract
Background: Functional mitral regurgitation (FMR) is common in patients
with myocardial infarction or dilated cardiomyopathies, and portends a
poor prognosis despite guideline-directed medical therapy. Surgical or
transcatheter mitral repair for FMR from recent randomized clinical
trials showed disappointing or conflicting results. Aims: To provide an
update on the role of surgical repair in the management of FMR.
Materials & Methods: A literature search was conducted utilizing
PubMed, Ovid, Web of Science, Embase and Cochrane Library. The search
terms included secondary/functional mitral regurgitation, ischemic
mitral regurgitation, mitral repair, mitral replacement, mitral
annuloplasty, transcatheter mitral repair, and percutaneous mitral
repair. Randomized clinical trials over the past decade were the
particular focus of this current review. Results: Recent data underlined
the complexity and poor prognosis of FMR. Guideline-directed medical
therapy and cardiac resynchronization, when indicated, should always be
applied. Accurate assessment of the interplay between ventricular
geometry and mitral valve function is essential to differentiate
proportionate FMR from the disproportionate subgroup, which could be
helpful in selecting appropriate transcatheter intervention strategies.
Surgical repair, most commonly performed with an undersized ring
annuloplasty, remains controversial. Adjunctive valvular or subvalvular
repair techniques are evolving and may produce improved results in
selected FMR patients. Conclusion: FMR resulted from complex
valve-ventricular interaction and remodeling. Distinguishing
proportionate FMR from disproportionate FMR is important in exploring
their underlying mechanisms and to guide medical treatment with surgical
or transcatheter interventions. Further studies are warranted to confirm
the clinical benefit of appropriate surgical repair in selected FMR
patients.