Abstract 11046: Pretest Probability by Combination of Duke Clinical Score and Coronary Artery Calcium Score for CT-verified Coronary Stenosis
Background: Traditional clinical algorithms for defining pretest probability of obstructive coronary artery disease (CAD) suffer from selection bias of inclusion of predominantly high-risk population suitable for conventional coronary angiography. We assessed the hypothesis that the combination of Duke Clinical Score (DCS) and coronary artery calcium score (CACS) can more correctly re-stratify the pretest probability.
Methods: The DCS and CACS were calculated for consecutive 3901 coronary CT angiography (CCTA) studies (M/F: 1942/1959, 66±12 y) performed at our institution between 08/2008 and 04/2013 for symptomatic patients without a known history of CAD, aortitis, Kawasaki disease or unacceptable motion artifacts. Patients were classified as having low (<30%), intermediate (30-70%), or high (>70%) pretest probability of obstructive CAD by DCS, and CACS was divided into 5 groups ( 0, 1-99, 100-399, 400-999, 1000-). The subjects were divided into 2 groups by 12/2012 (group A: 3528 (M/F: 1760/1768, 66±12y) for making a re-stratification table and group B: 373 (M/F: 182/191, 67±12y) for verification). Performance of the DCS and the combination of DCS and CACS for significant obstructive coronary stenosis (>50%) detection was evaluated by the Area Under the Curve (AUC) of the Receiver Operating Characteristic Curve.
Result: Gender, age, body weight, height, CACS or DCS was not significantly different between group A and B, respectively. Re-stratification by the combination of DCS and CACS was shown in the Table. The AUC of DCS was 0.711 in group A, and the AUC of the combination was 0.823 in group B. And, 52% patients of CACS>1000 in group A could not have evaluable CT image for luminal stenosis at least one coronary segment due to severe calcification even if without motion artifacts on CCTA
Conclusion: The combination of DCS and CACS for significant coronary stenosis detection was superior to DCS only. CCTA should be performed after estimating DCS and CACS.
- © 2013 by American Heart Association, Inc.