Karen Rodriguez, Presenter: Nothing to Disclose

Veit Sandfort MD, Abstract Co-Author: Nothing to Disclose

Puskar Pattanayak MBBS, FRCR, Abstract Co-Author: Nothing to Disclose

Shenghan Lai, Abstract Co-Author: Nothing to Disclose

Davis M. Vigneault BS, Abstract Co-Author: Nothing to Disclose

Marissa Mallek, Abstract Co-Author: Nothing to Disclose

Andrew Sams, Abstract Co-Author: Nothing to Disclose

Christopher Sibley, Abstract Co-Author: Nothing to Disclose

David A. Bluemke MD, PhD, Abstract Co-Author: Research support, Siemens AG

The relationship of calcium score (CAC) and risk factors has been determined. The purpose of this study is to assess the relationship between total coronary plaque burden (including noncalcified plaque) and cardiovascular risk factors as assessed by coronary CTA.

149 subjects were recruited in this ongoing, prospective study designed to evaluate the effect of HMG-CoA reductase inhibitors on atherosclerosis progress. Eligible subjects were >55 years of age, eligible for statin therapy, and had no known history of cardiovascular disease. Coronary artery imaging was performed using contrast enhanced CT angiography with a 320-detector row scanner. Images were analyzed using QAngioCT software v2.0.5 (Medis Medical Imaging Systems, Netherlands) using a lumen attenuation adaptive algorithm. Coronary wall thickness was evaluated in the total coronary artery tree for vessels > 2 mm diameter. Plaque index was defined as plaque volume divided by coronary length. Noncalcified plaque burden was defined as the sum of fibrous and fibrous fatty plaque. 

The average age was 66±6.5 years (38% women). Median coronary artery calcium was 65 (IQR 1-253). In univariate analysis, total plaque index was greater in men than women (42.7±10.6 vs 34.1±8.6 mm2, p=<0.001), and in patients with higher BMI (r=0.21, p=0.004). In multivariate analysis controlling for all risk factors but CAC, total plaque index was higher in men than women (standardized β=10.6 ; p=<0.001) and in patients with higher BMI (β=0.5 ; p=<0.001). In multivariate analysis, noncalcified plaque index was significantly correlated with LDL (β=0.05, p=0.01) and diabetes (β=4.0, p=0.04) but not with BMI (p=0.28).

Body mass index is a major determinate of total plaque burden as assessed by coronary CT angiography, independent of calcium score. LDL and diabetes, but not BMI, were also associated with greater noncalcified plaque burden.

Total coronary plaque burden by CTA may provide additional and independent prognostic information beyond traditional risk factors. BMI is an important modifiable risk factor.

Rodriguez, K, Sandfort, V, Pattanayak, P, Lai, S, Vigneault, D, Mallek, M, Sams, A, Sibley, C, Bluemke, D, Total Coronary Plaque Volume by Coronary CT Angiography: Relationship between Plaque Burden and Risk Factors.  Radiological Society of North America 2014 Scientific Assembly and Annual Meeting, - ,Chicago IL. http://archive.rsna.org/2014/14011337.html