Abstract From the Emerging Science Series, February 29, 2012
Mitral Valve Annuloplasty in Addition to Coronary Artery Bypass Grafting Improves Functional Capacity and Promotes Reverse Left Ventricular Remodelling: Preliminary Results of the Randomised Ischemic Mitral Evaluation Trial
K. M. John Chan, John R Pepper, RIME Trial Investigators, Imperial Coll London, Royal Brompton & Harefield NHS Trust, London, United Kingdom
Background: The optimal treatment of moderate functional ischemic mitral regurgitation (FIMR) is unknown. There is controversy over whether the addition of mitral valve annuloplasty (MVA) to coronary artery bypass grafting (CABG) improves outcome. Hypothesis: We assessed the hypothesis that MVA in addition to CABG improves functional capacity, reverses left ventricular (LV) remodelling, and reduces mitral regurgitation severity compared to CABG alone. Methods: 60 patients with moderate FIMR (effective regurgitant orifice area 0.2–0.4 cm2) referred for CABG were randomised to either CABG alone (Group 1) or CABG plus MVA (Group 2). Cardiopulmonary exercise testing, echocardiography, cardiovascular magnetic resonance imaging and plasma BNP levels were measured at baseline and one year. Results: At one year following surgery, peak oxygen consumption improved by a significantly greater amount in Group 2 compared to Group 1 (3.0±0.6 ml/kg/min versus 1.0±0.4 ml/kg/min; P=0.008). In addition, left ventricular (LV) volumes, LV sphericity, and mitral regurgitation severity decreased by significantly greater amounts in Group 2 compared to Group 1 (LVESVI decrease 24.4% versus 10.2%, P=0.05; LV sphericity decrease 17.9% versus 1.7% increase, P=0.01; mitral regurgitant volume decrease 69.2% versus 14.5%, P=0.005). Plasma BNP levels were also significantly less in Group 2 compared to Group 1 (54.8±7.2 pmol/l versus 108.9±11.4 pmol/l, P=0.001). Conclusion: Compared to CABG only, the addition of MVA to CABG in moderate FIMR significantly improves functional capacity, reverses LV remodelling, restores LV geometry, and reduces mitral regurgitation severity.
K. Chan: None. J.R. Pepper: None. R. Investigators: None.
- © 2012 American Heart Association, Inc.