Abstract 3037: Long-Term Positive Left Ventricular Remodeling After Correction of Severe Organic Mitral Regurgitation: A Pilot Cardiovascular Magnetic Resonance Study

Background : One of the goals of referring patients with chronic severe organic mitral regurgitation (MR) for corrective mitral valve surgery (MVR) is preservation of postoperative global left ventricular (LV) systolic function. Using cardiovascular magnetic resonance (CMR) methods, we have previously reported an intermediate decline in postoperative LV ejection fraction (LVEF). We hypothesized that years following successful surgical correction, there would be evidence of ongoing positive ventricular remodeling with improvement in systolic function and used quantitative CMR to prospectively test this hypothesis. Methods : Fourteen patients (50% female, 55 +/− 11.3 yrs) underwent elective MVR for severe organic MR. Quantitative CMR was performed preoperatively and at median times of 3 months and 27 months following MVR. Results : See Table . At 3 mo, postoperative LVEF declined by 27% (p<0.001) but recovered to preoperative values at 27 mo (p=NS vs. pre, p<0.001 vs. 3 mo). Twelve (86%) of 14 patients had normal LVEF 27 mo after MVR. LV end diastolic volume index (LVEDVI) declined by 32% at 3 mo (p<0.001) and by an additional 9% at 27 mo (p<0.001 vs. pre, p<0.019 vs. 3mo), with 12 (86%) of 14 patients achieving normal volumes. LV mass index (LVMI) declined by 22% at 3 mo (p<0.001) with a further decline of 17% at 27 mo (p<0.001 vs. pre, p<0.001 vs. 3 mo). All patients had normal LVMI at long-term follow-up. Conclusions : In this prospective pilot study, we demonstrate ongoing positive LV remodeling beyond the intermediate postoperative period. These changes likely reflect normalization of cardiac hemodynamics following correction of MR with decreases in ventricular volumes and mass as well as preservation of systolic function. Comparison of LV parameters preoperatively, at 3 mo, and at 27 mo following MVR