Abstract 18200: Mitral Valve Annuloplasty Versus Mitral Valve Replacement for Ischemic Mitral Regurgitation: An Exercise Echocardiographic Study
Background: Mitral valve annuloplasty (MVA) and mitral valve replacement (MVR) are common strategies for the management of functional ischemic mitral regurgitation (FIMR). However, both surgical strategies may have hemodynamics limits.
Methods and Results: We performed resting and exercise echocardiography in 56 patients, matched for, indexed effective orifice area (IEOA), left ventricular ejection fraction and systolic pulmonary arterial pressure (SPAP), following MVA or MVR and coronary artery bypass grafting. There was no significant difference between the 2 groups regarding baseline demographic and clinical data. The percentage of exercise-induced increase in mean and peak mitral gradients was higher in MVA group (mean gradient: +196.7±149% vs. +118.8±83.8%, p=0.02; peak gradient: +203.7±299.7 vs. +89.4±84.4%, p=0.06). Exercise SPAP increased to a higher extent in MVA group (from 37±9 to 54±13mmHg, compared to MVR: from 33±6 to 44±6mmHg, p=0.0001). Exercise SPAP≥50mmHg was more frequent in MVA group than in MVR group (32.1% vs. 14.2%, p=0.009). Both exercise-induced improvement in effective orifice area (EOA) and IEOA were better in MVR (MVR: +0.19±0.5 vs. MVA:-0.12±0.5cm², p=0.009, for EOA; MVR: +0.13±0.2 vs. MVA 0.05±0.28cm²/m²,p=0.007, for IEOA). Exercise IEOA was correlated with exercise SPAP (r=-0.45; p=0.01). On multivariate analysis, performing MVA, postoperative IEOA and mean mitral gradients were independent determinants of SPAP during exercise.
Conclusions: In patients with FIMR, MVA may cause functional mitral stenosis, especially during exercise, when compared with MVR. Performing MVA was associated with poor exercise mitral hemodynamic performance, lack of mitral valve opening reserve, and higher rate of postoperative exercise pulmonary hypertension.
- © 2012 by American Heart Association, Inc.