Abstract 11346: Cardiac Magnetic Resonance Predictors of Left Ventricular Functional Improvement After Mitral Valve Repair for Cardiomyopathy
Background: We sought to identify cardiac magnetic resonance imaging (CMR) predictors of functional improvement after mitral valve repair for cardiomyopathy.
Methods: CMR was obtained in 61 patients (62±2 years, 42 males) before mitral valve annuloplasty for ischemic (n=54) or non-ischemic (n=8) cardiomyopathy from 2003 to 2007. CABG was also performed in 52 patients (52 to the LAD, 44 to the circumflex and 41 to the right coronary artery). Follow-up LVEF was assessed by echocardiogram at 20±3 months after surgery. Change in LVEF was analyzed as a continuous variable. Preoperative CMR variables (LVEF, LV end systolic (LVESVi) and LV end diastolic (LVEDVi) volume indices, LV wall viability [percent viable: 0:0%, 1:1-25%, 2:26-50%, 3:51-75%, 4:76-100%] and motion [0:Aneurysmal, 1:Dyskinetic, 2:Akinetic, 3:Hypokinetic, 4:Normal]) were analyzed for predictors of LVEF improvement using linear regression analysis adjusted for baseline and procedural variables.
Results: There was no in-hospital mortality. There were 7 late deaths at a mean follow-up of 2.0±0.3 years. Mitral regurgitation improved in severity from 2.6±0.1 to 1.2±0.1 (p<0.001). LVEF improved from 24±2% to 36±2% (p<0.001). CMR predictors of LVEF improvement were anterior wall motility and low LVEDVi. Each preoperative increase by one unit on the scale for anterior wall motion has a +7.9 impact on improvement in LVEF (CI 2.6 to 13.1, p=0.0004). Increasing preoperative LVEDVi by increments of 20 ml/m2 has a -3.4 impact on improvement in LVEF (CI -5.4 to -1.4, p=0.001). Myocardial viability was not a predictor of improvement (p>0.14).
Conclusions: Myocardial viability does not predict improvement in LVEF. Preserved anterior wall motility and less remodeled ventricle predict LVEF improvement after mitral valve repair for cardiomyopathy. We conclude that patients with preserved anterior wall motion should undergo early mitral valve repair before extensive remodeling develops.
- © 2011 by American Heart Association, Inc.