Evaluating Coronary Stenosis With Parameters Of Corrected Coronary Luminal Attenuation In CT Angiography

Objective To evaluate coronary stenosis with parameters of corrected coronary luminal attenuation in coronary computed tomographic angiography.Materials and Methods Retrospectively analyzed the CT images of patients who had undergone coronary CTA and invasive coronary angiography successively within thirty days in our medical center from July 2016 to July 2017,coronary luminal attenuation most proximal and distal to the stenosis within 5-10 mm and the luminal attenuation in descending aorta on the same axial section were measured,and recorded C1、C2、A1、A2,giving definitions of difference of corrected coronary opacification(DCCO)= C1 / A1-C2 / A2、ratio of corrected coronary opacification(RCCO)=(C1 / A1)/(C2 / A2)、ratio of coronary opacification(R)= C1 / C2.Evaluating the correlations between parameters of corrected coronary luminal attenuation and the severity of coronary artery stenosis,including the ability of diagnosing the obstructive coronary stenosis(diameter stenosis ≥ 50%)with sensitivity,specificity,positive predictive value,negative predictive value,accuracy and area under receiver operating characteristic(ROC)curve,all the groupings were conducted with invasive coronary angiography using as the standard of reference.Results A total of 104 arteries were assessed,the parameters of corrected luminal attenuation(DCCO,RCCO,R)were associated with the classification of coronary stenosis,differences of all corrected luminal attenuation parameters between no stenosis and mild stenosis,no stenosis and moderate stenosis,no stenosis and severe stenosis,mild stenosis and severe stenosis were significant(P < 0.05).There was also significant difference of the corrected luminal attenuation parameters between nonobstructive and obstructive coronary stenosis(P < 0.05).ROC curve areas showed the highest diagnostic efficacy when DCCO ≥ 0.165,RCCO ≥ 1.185,R ≥ 1.175,DCCO + CTA ≥ 0.043,RCCO + CTA ≥ 0.099,R + CTA ≥ 0.106,and the ROC curve areas were 0.816,0.820,0.812,0.860,0.860,0.854.The ROC curve areas were 0.763 of CTA alone.Moreover,ROC curve areas of all corrected luminal attenuation parameters combining with CTA were higher than CTA alone(P < 0.05).Conclusion Parameters of corrected coronary luminal attenuation(DCCO,RCCO,R)in CT angiography may increase the diagnostic efficiency of significant coronary stenosis compared with coronary CT angiography alone.