The Natural History of Severe Calcific Mitral Stenosis

BACKGROUND Prevalence of calcific mitral stenosis (MS) increases with age; however, its natural history and relation to cardiac symptoms or comorbidities are not well defined. OBJECTIVES This study assessed the prevalence of symptoms, comorbidities, and determinants of all-cause mortality in patients with severe calcific MS. METHODS The authors retrospectively investigated adults with isolated severe calcific MS and mitral valve area ≤1.5 cm2 from July 2003 to December 2017. Inactivity was defined as requirement for assistance with activities of daily living. RESULTS Of 491 patients with isolated severe MS, calcific MS was present in 200 (41%; age 78 ± 11 years, 18% men, 32% with atrial fibrillation). Charlson Comorbidity Index was 5.1 ± 1.7 and 14 (7%) were inactive. Mitral valve area and transmitral gradient (TMG) were 1.26 ± 0.19 cm2 and 8.1 ± 3.8 mm Hg, respectively. Symptoms were present at baseline in 120 (60%); 20 (10%) developed symptoms during follow-up of 2.8 ± 3.0 years. Kaplan-Meier survival at 1 year was 72% without intervention. Inactivity (hazard ratio HR: 6.59; 95% confidence interval CI: 3.54 to 12.3; p 5 (HR: 1.53; 95% CI: 1.04 to 2.26; p < 0.01), TMG ≥8 mm Hg (HR: 1.68; 95% CI: 1.12 to 2.51; p = 0.012), and right ventricular systolic pressure ≥50 mm Hg (HR: 2.27; 95% CI: 1.50 to 3.43; p < 0.01) were independently associated with mortality. Symptoms were not associated with mortality. CONCLUSION Patients with isolated severe calcific MS had a high burden of comorbidities, resulting in high mortality without intervention. Symptoms were reported in 60%, but not associated with mortality. TMG ≥8 mm Hg and right ventricular systolic pressure ≥50 mm Hg were independently associated with mortality.