Background: Long-term effects of restrictive mitral annuloplasty (RMA), especially on hemodynamics and left ventricular (LV) function in patients with functional mitral regurgitation (MR), have not been fully investigated.
Methods and results: From 1999 to 2008, 44 patients with refractory heart failure and functional MR underwent RMA with stringent downsizing of the mitral annulus. Serial echocardiography was performed to evaluate LV function (reverse remodeling), estimated systolic pulmonary artery pressure (PAP) and mitral valve geometry at baseline and at discharge, and annually thereafter. Cardiac catheterization was performed at baseline, and at discharge to evaluate acute hemodynamic change. There were 3 early deaths, and the 5-year survival rate was 78 ± 8%. In 41 survivors the clinical symptoms, stratified according to New York Heart Association class, significantly improved after surgery. Postoperative cardiac catheterization showed significant unloading for left ventricle, as well as improvement in LV systolic function. Serial echocardiography showed that improvements in LV function and systolic PAP were sustained in the majority of patients. Multivariate Cox regression analysis identified preoperative pulmonary hypertension (systolic PAP>60 mm Hg) as the significant predictor for postoperative adverse cardiac events.
Conclusions: RMA for functional MR resulted in sustained improvement of hemodynamics and LV function over time. Additional studies are needed to define the negative impact of preoperative pulmonary hypertension in patients with this condition.