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Mitral annular calcification (MAC) is recognized as a rare cause of mitral stenosis (MS). However, little is known regarding its natural history. In this study, we aimed to define the progression of MS in patients with severe versus non-severe MAC.
Database for the years 1996 through 2013 was searched for patients who had severe MAC. MAC was graded into none (0), mild (1), moderate (2), or severe (3) in a semi-quantitative manner. It was then grouped into severe (3) and non-severe (1,2) groups. Patients were included if they had MAC at their index study and underwent ≥ 2 studies in the period of ≥ 2 years. Patients with prior mitral valve (MV) surgery, rheumatic heart disease, or other identifiable MV disease were excluded. MV gradients were evaluated with peak and mean MV gradients, right ventricular systolic pressure (RVSP) and mitral valve area (MVA) from pressure half time (PHT) method. Mixed model analysis was applied obtain the progression rates.
A total of 2995 patients (18794 studies) were included. Data are expressed as mean ± standard deviation. Population age at index study was 71 ± 11 years. Follow up time was 5.4 ± 3.2 years. Number of echocardiograms performed per patient was 5 ± 3. MS progression rates between non-severe and severe MAC were: peak gradient (0.92 vs 1.849mmHg, p <0.001), mean gradient (0.041 vs 0.561mmHg, p< 0.001), RVSP (3.398 vs 5,249mmHg, p <0.001), MVA (0.163 vs -0.052cm2, p < 0.001).
Compared to non-severe MAC, patients with severe MAC were had faster progression of mitral valvular gradients. Furthermore, the rate of MS progression overall was small over time in both groups.
STRUCTURAL: Valvular Disease: Mitral