Abstract 16071: In vivo Analysis of Coronary Arterial Calcification Components by Single-Source Coronary Dual-Energy Computed Tomography With Rapid Tube Voltage Switching
Objective: Coronary arterial calcification (CAC) is one of the prominent features of an advanced form of atherosclerotic process. CAC has been reported to accompany a risk of coronary artery disease. However, biological significance of CAC towards atherosclerotic process and influence of CAC on prognosis of patients with atherosclerosis still remain the issue of debate. A previous study showed that hydroxyapatite (HAP), the major component of bone, is the main component of arterial calcification. Calcium carbonate, calcium oxalate monohydrate, dicalcium phosphate dehydrate (DCPD), and octacalcium phosphate (OCP) were also reported to contribute to vascular calcification in addition to HAP. In this study, we analyzed the components of CAC in vivo by using single-source coronary dual-energy computed tomography (DECT).
Methods: Consecutive 35 patients underwent prospectively ECG-gated coronary DECT with rapidly switching the tube voltage from 80 to 140 kVp during a single projection in as little as 0.25 milliseconds (GSI Cardiac; GE Healthcare, Milwaukee, WI) by a single-source DECT scanner (Discovery CT750 HD, GE Healthcare) from June 1st through December 31th, 2012. CAC was detected in 28 out of 35 patients. We placed a region of interest within each CAC to measure its effective atomic number (EAN) using a dedicated workstation (Advantage Windows 4.6, GE Healthcare). We compared the EAN and its histogram for each CAC with those of HAP and other various calcium phosphates, including DCPD and OCP.
Results: We detected a total of 145 CACs in 35 patients. Only 4 out of 145 CACs showed the histogram of the EAN comparable with that of HAP (16.09). The histogram was similar to that of DCPD (11.21) in 8 CACs. The histogram for the remaining 133 CACs was located between that of HAP and that of DCPD.
Conclusion: Although it has been postulated that the major component of CAC is HAP, our study suggests that CAC may be heterogeneously composed of various calcium phosphates in addition to HAP, since this histogram analysis disclosed most of the EAN for each CAC less than that of HAP.
- © 2013 by American Heart Association, Inc.