Degenerative mitral stenosis by echocardiography: presentation and outcome

Aims Degenerative mitral stenosis (DMS) is due to degenerative mitral annular calcification (MAC) and valvular calcification. However, DMS impacts on the outcome, and therefore, potential treatment needs are poorly known. We aimed at evaluating survival after DMS diagnosis by Doppler echocardiography in routine practice. Methods and results A cohort of 2937 (75 +/- 12 years, 67% women) consecutive patients were diagnosed between 2003 and 2014 with DMS (diastolic mean gradient >= 5 mmHg), with analysis of short- and long-term survival. All patients had overt mitral annular/valvular degenerative calcification without rheumatic involvement. Mean gradient was 6.5 +/- 2.4 mmHg, and DMS was considered mild in 50%, moderate in 44%, and severe in 6%. DMS was associated with left atrial enlargement (52 +/- 23 mL/m(2)) and elevated pulmonary pressure (49 +/- 16 mmHg) despite generally normal ejection fraction (61 +/- 13%). DMS was associated with frequent comorbid conditions (74% hypertension, 58% coronary disease, and 52% heart failure) and humoural alterations (haemoglobin 11.3 +/- 1.8 g/dL and creatinine 1.5 +/- 1.4 mg/dL). One-year mortality was 22%, most strongly related to older age, higher comorbidity, and abnormal haemoglobin/creatinine but only weakly to DMS severity (with anaemia 42% irrespective of DMS severity, P = 0.99; without anaemia 18, 23, and 28% with mild, moderate, and severe DMS, respectively, P < 0.0004). Long-term mortality was high (56% at 5 years) also mostly linked to aging and weakly to DMS severity [with anaemia P = 0.90; without anaemia: adjusted-hazard ratio: 1.30 (1.19-1.42), P < 0.0001, for moderate vs. mild DMS and 1.63 (1.34-1.98), P < 0.0001, for severe vs. mild DMS]. Conclusion DMS is a condition of the elderly potentially resulting in severe mitral obstruction and haemodynamic alterations. However, DMS is frequently associated with severe comorbidities imparting considerable mortality following diagnosis, whereas DMS severity is a weak (albeit independent) determinant of mortality. Hence, patients with DMS should be carefully evaluated and interventional/surgical treatment prudently considered in those with limited comorbidity burden, particularly without anaemia. Keywords: Degenerative Mitral Stenosis; Outcome; Natural history; Ecocardiography; Mitral Stenosis.