Survival in Patients with Degenerative Mitral Stenosis: Results from a Large Retrospective Cohort Study

Abstract

Severe mitral annular calcification causing degenerative mitral stenosis (DMS) is increasingly encountered in patients undergoing mitral and aortic valve interventions. However, its clinical profile and natural history and the factors affecting survival remain poorly characterized. The goal of this study was to characterize the factors affecting survival in patients with DMS. An institutional echocardiographic database was searched for patients with DMS, defined as severe mitral annular calcification without commissural fusion and a mean transmitral diastolic gradient of ≥2mmHg. This resulted in a cohort of 1,004 patients. Survival was analyzed as a function of clinical, pharmacologic, and echocardiographic variables. The patient characteristics were as follows: mean age, 73±14 years; 73% women; coronary artery disease in 49%; and diabetes mellitus in 50%. The 1- and 5-year survival rates were 78% and 47%, respectively, and were slightly worse with higher DMS grades (P=.02). Risk factors for higher mortality included greater age (P<.0001), atrial fibrillation (P=.0009), renal insufficiency (P=.004), mitral regurgitation (P<.0001), tricuspid regurgitation (P<.0001), elevated right atrial pressure (P<.0001), concomitant aortic stenosis (P=.02), and low serum albumin level (P<.0001). Adjusted for propensity scores, use of renin-angiotensin system blockers (P=.02) or statins (P=.04) was associated with better survival, and use of digoxin was associated with higher mortality (P=.007). Prognosis in patients with DMS is poor, being worse in the aged and those with renal insufficiency, atrial fibrillation, and other concomitant valvular lesions. Renin-angiotensin system blockers and statins may confer a survival benefit, and digoxin use may be associated with higher mortality in these patients.