Feasibility of Measuring Pericoronary Fat from Precontrast Scans: Effect of Iodinated Contrast on Pericoronary Fat Attenuation

Abstract Background Pericoronary adipose tissue (PCAT) attenuation has been identified as a marker for cardiovascular risk. The effect of contrast enhancement on fat attenuation is unknown. We aim to compare precontrast coronary scans to postcontrast CCTA for quantification of pericoronary fat volume and attenuation. Methods Thin slice pre- and post-contrast studies obtained at 120 kVp, heart rate Results Of 119 study pairs, the average RCA diameter was highly correlated at 3.85mm (postcontrast) and 3.84mm (precontrast), r=0.97, p Conclusion Pericoronary fat enhances with iodinated contrast, potentially explaining some of its risk-predictive capabilities. Fat attenuation and volume can be reliably measured from precontrast calcium scans, with volume quantification showing particularly strong correlation. Excellent inter- and intra-reader agreement is also demonstrated.