Accuracy of coronary computed tomographic angiography in evaluation of coronary stenosis caused by different plaque subtypes

Objective To evaluate the diagnostic accuracy of coronary computed tomography angiography (CCTA) on coronary stenosis with different plaque subtypes. Methods From June 2013 to June 2015, 80 patients were admitted for CCTA and coronary angiography in our hospital, and their imaging findings were selected. Totally 150 stenotic vessels were chosen as observation objects. According to CT findings, the plaques types were classified as non-calcified (n=45), mixed (n=58) and calcified (n=57). Choosing stenosis greater than 75% as the critical point, they were divided into two groups as severe stenosis and non-severe stenosis. The diagnostic accuracy of CCTA on coronary stenosis was evaluated. Results The sensitivity and specificity of coronary stenosis by CCTA in the non-calcified group were 95.8% and 90.5% with predictive value for a positive result (PV⁺) of 92%, predictive value for a negtive result (PV^-) of 95%, consistency rate of 93.3%, and kappa coefficient of 0.866; The sensitivity and specificity of coronary stenosis by CCTA in the mixed group were 97.5% and 83.3% with PV⁺of 93%, PV^-of 93.75%, consistency rate of 93.1%, and kappa coefficient of 0.834; The sensitivity and specificity of coronary stenosis by CCTA in the calcified group were 93.3% and 37% with the PV⁺of 62%, PV^-of 83.3%, consistency rate of 66.7%, and kappa coefficient of 0.313. Conclusion The accuracy of CCTA in detecting non-calcified plaques and mixed plaques of the coronary arteries is high, but it is quite low for the determination of calcified plaque.