Effects of Mitral Calcification in Severe Aortic Stenosis with Severe Mitral Regurgitation on Left Heart Remodeling, Surgical Strategy, and Outcomes.

Abstract

Objectives: 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.

Methods: From July 1998 to 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). Mitral calcium was localized and quantified on preoperative computed tomography. Random forest methodology was used to correlate calcium volume with cardiac morphology and function. Median follow-up for survival was 4.1 years; 25% were followed ≥14 years.

Results: Larger 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) versus 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 demonstrated early postoperative mortality was strongly associated with subvalvular mitral calcification, but late mortality was not associated with calcium volume or location.

Conclusions: Larger mitral calcium volume is a marker of late-stage cardiac remodeling associated with more extensive mitral valve intervention, but it is not associated with long-term mortality. Quantitative analysis of mitral calcification with computed tomography can aid in patient selection and surgical management decisions in this complex patient population.