Usefulness of helical computed tomography in detection of mitral annular calcification as a marker of coronary artery disease

Abstract

Background: Mitral annulus calcification (MAC) may be a form of atherosclerosis. The goal of the present work was to investigate whether helical CT can determine the presence of MAC and to clarify its possible association with coronary artery disease (CAD) in elderly patients.

Design and methods: Three hundred and twenty-nine consecutive elderly patients (165 men and 164 women, age range 60-79 years) underwent double helical CT of the heart to determine MAC and coronary calcifications (CC) according to a previously described protocol.

Results: MAC was documented in 60 patients (25 men, 35 women; mean age 69 +/- 4.5 years, range 60-78 years). The non-MAC group (control) included 269 patients (140 men, 129 women; mean age 67 +/- 4.6 years, range 60-79 years). Age was the only risk factor which had significant association with MAC (p = 0.01). A significant difference was found between MAC and control group for mean total CC score and advanced CC (total CC > 300) (323 +/- 565 vs. 184 +/- 429, p = 0.033 and 30% vs. 16%, p = 0.017, respectively). A significant difference was also found between groups for the prevalent proven CAD (30% vs. 16%, p = 0.008). Stepwise logistic regression analysis identified age [odds ratio (OR) 3.3, 95% confidence interval (CI) 1.7-6.4, p < 0.001)], gender (male) (OR 3.1, 95% CI 1.6-6.0, p = 0.001), and MAC (OR 2.4, 95% CI 1.2-5.0, p = 0.016) as the independent variables significantly associated with CAD. The independent variables significantly associated with advanced CC (TCS > 300) were MAC (OR 2.6, 95% CI 1.3-5.2, p = 0.005), gender (male) (OR 2.3, 95% CI 1.2-4.2, p = 0.012) and age (OR 1.9, 95% CI 1.0-3.7, p = 0.052).

Conclusions: Our study demonstrated the usefulness of helical computed tomography in the detection of mitral annular calcification as an additional marker of prevalent CAD. However, the diagnostic significance of the MAC detection is relatively minor and should not be considered as a direct proof for coronary atherosclerosis.