Effects of mitral calcification in severe aortic stenosis with severe mitral regurgitation on left heart remodeling, surgical strategy, and outcomes.

Abstract

To localize and quantify mitral calcification associated with severe aortic stenosis and severe mitral regurgitation and determine its association with cardiac remodeling, operative management, and long-term survival. Between July 1998 and July 2010, 158 patients with severe aortic stenosis, severe mitral regurgitation, and mitral calcification underwent surgical aortic valve replacement (SAVR; n = 49) or SAVR plus mitral valve repair (SAVR+MVr; n = 67) or replacement (SAVR+MVR; n = 42) at our institution. Mitral calcium was localized and quantified by a preoperative computed tomography (CT) scan. Random forest methodology was used to correlate calcium volume with cardiac morphology and function. The median follow-up for survival was 4.1 years; 25% of patients were followed for ≥14 years. Greater calcium volume was associated with degenerative mitral disease, higher ejection fraction, smaller left ventricular end-systolic volume, and SAVR+MVR (median calcium volume, 3.4 cm³) compared to SAVR (median calcium volume, 1.0 cm³) or SAVR+MVr (median calcium volume, 0.41 cm³). Ten-year mortality was higher in patients with more mitral calcification (terciles: 7.1% vs 16% vs 25%), subvalvular involvement (8.1% vs 18%), and SAVR+MVR (5.4% vs SAVR; 13% vs SAVR+MVr = 26%). Multivariable analysis showed that early postoperative mortality was strongly associated with subvalvular mitral calcification, but late mortality was not associated with calcium volume or location. Greater mitral calcium volume is a marker of late-stage cardiac remodeling associated with more extensive mitral valve intervention but not with long-term mortality. Quantitative analysis of mitral calcification with CT can aid patient selection and surgical management decisions in this complex patient population.