Abstract
The prevalence and degree of mitral annular calcification (MAC) in elderly cases of hypertrophic cardiomyopathy with asymmetric septal hypertrophy (ASHCM) were studied in comparison with healthy elderly and chronic hypertensive elderly with concentric left ventricular hypertrophy (HT+LVH) by echocardiography. In seven elderly patients with ASHCM (mean age 77.3±8.1 years) severe MAC was observed in all cases (1 male and 6 females) and systolic anterior motion of the mitral valve (SAM) was present in 3 cases, incomplete in 2 and absent in 2 cases. Of 57 healthy elderly with a mean age of 78.8±8.8 years, 8 subjects (1 male and 7 females, 14%) showed MAC. The prevalence of MAC was 0% in the sixties, 14% in the seventies, 16% in the eighties and 29% in the nineties. MAC was severe in four subjects above eighty years old. In 3 cases with HT+LVH with a mean age of 72.3±4.7 years no MAC was observed and SAM was present in one, partially observed in one and absent in one case, respectively. Serum calcium (Ca) and phosphorus (P), reported to be related with the formation of MAC, and fasting blood sugar level (FBS) were evaluated. In healthy elderly with MAC, serum Ca was 8.78±0.46mg/dl, P 3.55±0.37mg/dl and FBS 97.75±29.01mg/dl. These values were 9.32±0.57mg/dl, 3.06±0.83mg/dl and 77.09±21.18mg/dl in healthy elderly without MAC and 8.64±0.49mg/dl, 3.61±0.39mg/dl and 92.75±13.84mg/dl in ASHCM and 8.63±0.25mg/dl, 3.13±0.35mg/dl and 93.00±4.58mg/dl in cases with HT+LVH. No statistically significant difference was ovserved among these groups for these values. In the present study, a high prevalence of MAC complicating to ASHCM was seen, but no relation was found between MAC formation and serum Ca levels. The chronic mechanical stress to the mitral valve apparatus due to the disproportionate contraction of the left ventricle because of ASH and due to elevated left ventricular pressure in the presence of LV outflow obstruction seemed to have been strongly involved in the formation of MAC in ASHCM.
