Evaluation of CTCA combined with CT first-pass myocardial perfusion imaging in diagnosing silent myocardial ischemia

DONG Xiaobo; LI Ying; ZHANG Zhonghui; TANG Jianzhong; GUO Qingle

Abstract：Objective To evaluate CTCA combined with CT first-pass myocardial perfusion imaging in diagnosing silent myocardial ischemia (SMI).Methods 72 patients with suspected SMI were included in this study.Myocardial perfusion imaging (MPI) and CTCA were performed in all patients.Taking MPI as the reference standard, the sensitivity, specificity, positive predictive value, negative predictive value and accuracy of CT first-pass myocardial perfusion imaging and CTCA combined with CT first-pass myocardial perfusion imaging in the diagnosis of SMI were evaluated, and the consistency with the diagnosis of MPI was analyzed.Results Technical success was achieved in all 72 cases.Compared with MPI, on patient-based level, the sensitivity, specificity, positive predictive value and negative predictive value of CT first-pass myocardial perfusion imaging in detecting SMI were 90.91%(40/44), 71.43%(20/28), 83.33%(40/48) and 83.33%(20/24) respectively, the accuracy was 83.33%(60/72).The consistency between CT first-pass myocardial perfusion imaging and MPI was evaluated with Kappa analysis, and Kappa value was 0.640 (P<0.05).The sensitivity, specificity, positive predictive value and negative predictive value of CTCA combined with CT first-pass myocardial perfusion imaging in detecting SMI were 95.45%(42/44), 75.00%(21/28), 85.71% (42/49) and 91.30%(21/23) respectively, the accuracy was 87.50%(63/72).The consistency between CTCA combined with CT first-pass myocardial perfusion imaging and MPI was evaluated with Kappa analysis, and Kappa value was 0.728 (P<0.05).On vessel-based level, the sensitivity, specificity, positive predictive value and negative predictive value of CT first-pass myocardial perfusion imaging and CTCA combined with CT first-pass myocardial perfusion imaging in detecting SMI were 88.89%(48/54), 89.51%(145/162), 73.85%(48/65), 96.03%(145/151) respectively and 92.59%(50/54), 90.74%(147/162), 76.92%(50/65), 97.35%(147/151) respectively, with the diagnostic accuracy being 89.35% and 91.20% respectively.The Kappa values were 0.734 and 0.780 respectively (both P<0.05).Conclusion CTCA combined with CT first pass my-ocardial perfusion imaging in the diagnosis of SMI has a high accuracy, as the "one stop" examination of coronary heart disease has a good clinical application prospect.