Preoperative and late postoperative mitral regurgitation in ventricular reconstruction: role of local left ventricular deformation.

Background: We sought to analyze the characteristics of local left ventricular deformation related to functional mitral regurgitation (MR) in post-anterior myocardial infarction scar, and to evaluate how local remodeling contributes to late development of MR after surgical ventricular reconstruction by endoventricular circular patch plasty repair.

Methods: Two hundred twenty-one consecutive patients (aged 60 +/- 9 years; 193 males) with previous transmural anterior infarction underwent heart catheterization both before and 1 year after endoventricular circular patch plasty repair. Preoperative global left ventricular shape determinants (eccentricity and circularity indexes), regional curvature and wall motion (centerline), and both preoperative and 1-year postoperative hemodynamic parameters (volumes, ejection fraction, capillary wedge and pulmonary artery pressures) were calculated.

Results: Forty-eight patients had (MR patients), and 173 did not have (NoMR patients) angiographic MR grade 2 or more preoperatively; at follow-up, 30 NoMR patients had MR (late MR [LMR]). Before surgery, MR patients had larger left ventricular volumes, higher capillary wedge and mean pulmonary artery pressures, and lower ejection fraction and cardiac index. The LMR patients had similarly high capillary wedge and pulmonary artery pressures as MR patients; otherwise, they did not differ from NoMR patients. Mitral regurgitation patients had wider lateral wall akinesia and greater inferior wall asynergy; the inferobasal region was hypokinetic in LMR patients. In MR patients, inferior wall systolic curvature was less negative; the inferobasal region had a more positive curvature in LMR patients.

Conclusions: Local deformation of the inferior wall with loss of systolic inward bending is associated with functional MR, while asynergy and systolic deformation of the inferobasal region and high capillary wedge pressure are prognostic signs of MR development late after endoventricular circular patch plasty repair.