Usefulness of routine aortic valve calcium score measurement for risk stratification of aortic stenosis and coronary artery disease in patients scheduled cardiac multislice computed tomography

OBJECTIVES: This study sought to investigate the clinical utility of aortic valve calcium score (AVCS) determined by using cardiac multislice computed tomography (MSCT). METHODS: Data of 1315 consecutive patients who underwent both conventional echocardiography and MSCT were reviewed. Degree of aortic stenosis (AS) was assessed according to mean pressure gradient (mPG) measured by echocardiography. Extent of coronary artery disease (CAD) derived by MSCT also was evaluated in 1173 patients who did not undergo prior coronary treatment. Both AVCS and coronary calcium score (CCS) were defined by Agatston units (AU) according to MSCT findings. RESULTS: A total of 613 of 1315 patients were defined as AVCS positive (mean, 100 AU [range, 31.0-380.0 AU]). AVCS showed significant correlations with mPG (Spearman's ρ = 0.81, p < 0.001), and CCS (ρ = 0.53, p < 0.001). Differential adequate cut-off values of AVCS were proved for predicting severe AS with mPG ≥ 40 mmHg (1596.5 AU; AUC, 0.88; sensitivity, 89.7%; specificity, 77.0%), and for predicting moderate AS with mPG ≥ 20 mmHg (886.5 AU; area under the curve [AUC], 0.91; sensitivity, 92.4%; specificity, 78.3%). Mean AVCS was higher with increased extent of CAD (none, 0 AU [range, 0-30 AU]; single vessel, 8.5 AU [range, 0-104 AU]; multivessel, 142 AU [range, 10-525 AU]; p < 0.001). The optimal cut-off value of AVCS for predicting multivessel disease was 49 AU (AUC, 0.77; sensitivity, 68.8%; specificity, 78.0%). CONCLUSIONS: AVCS might be a surrogate marker not only for AS grading but also for CAD progression. Therefore, routine AVCS assessment could be useful for risk stratification.