Abstract 13739: Progression of Mitral Stenosis in Patients With Severe Mitral Annular Calcification and Chronic Kidney Disease

Abstract

Background: Severe mitral annular calcification (MAC) is recognized as a rare cause of mitral stenosis. However, little is known regarding its relationship with chronic kidney’s disease (CKD). We evaluated progression of mean mitral valve (MV) gradients and the right ventricular systolic pressures (RVSP) over time in patients with CKD. Methods: Database for the years 1996 through 2013 was searched for patients with severe MAC. MAC was graded in a semi-quantitative manner. Patients were included if they had severe MAC at their index study, had ≥ 2 studies in the period of ≥ 2 years, and had glomerular filtration rate estimated ≤ 3 months from the index study. Patients with prior MV surgery, rheumatic heart disease, or other MV disease were excluded. CKD was classified by 5 conventional stages. The slope of regression line using all studies of a given patient was used to determine the progression rate. Results: 924 patients (7002 studies) were included. Data are expressed as mean ± standard deviation. Study population age was 72 ± 11 years. Follow up time was 4.8 ± 2.8 years. Number of echocardiograms performed per patient was 8 ± 5. Index MV gradient was 3.9 ± 3.2 mmHg with progression rate 0.13 ± 0.86 mmHg / year (p = 0.0001). Index RVSP was 39 ± 15 mmHg with progression rate 0.97 ± 4.49 mmHg / year (p = 0.0001). Progression appeared slower in younger (<65, n=189) than older (≥65, n = 735) patients (MV gradient p=0.07, RVSP p= 0.10). 66 patients had MV surgery with MV gradient at the time of surgery being 13.76 ± 4.15 mmHg. There were no significant differences in the progression rate among CKD stages (MV gradient p = 0.11, RVSP p = 0.87) or with dialysis status (n=41, MV gradient p= 0.50, RVSP p= 0.13). Conclusion: While there tended to be faster rate of progression of mitral stenosis in older patients with severe MAC, CKD class was not a differentiating factor. It appears that mitral stenosis in patients with severe MAC progress more in older patients but not necessarily in patients with poor kidney function.