The diagnostic value of dual source coronary CT angiography combined with dynamic CT myocardial perfusion imaging in coronary artery disease

Objective To evaluate the diagnostic value of one-stop cardiac CT (stress dynamic CT-MPI combining with CTA) in CAD. Methods Thirty patients underwent CCTA combined with stress dynamic CT-MPI and stress SPECT-MPI including 16 patients underwent ICA were retrospectively enrolled. All procedures were performed within 2 weeks without related treatment. CT-MPI and SPECT-MPI were evaluated visually and MBF was quantified according to dynamic CT-MPI which was compared through paired t test. The diagnostic value of CT-MPI for myocardial ischemia was evaluated with SPECT-MPI as the reference standard. The consistency between the two techniques was determined by Kappa test. With SPECT combined with ICA as the reference standard, we evaluated the value of CT-MPI and its combination with CCTA in the diagnosis of CAD with hemodynamic stenosis. Results On stress CT-MPI, 19 of 30 patients and 52 segments were evaluated with myocardial perfusion defects. There was a significant difference in MBF values between normal[(117.61±29.82)ml·100 ml-1·min-1] and hypoperfused [(80.60±22.15)ml·100 ml-1·min-1] segments (t=15.764,P<0.001). With SPECT as reference standard, the sensitivity, specificity were 94.12% (32/34), 95.80% (456/476) on the vessel basis. The Kappa value of the two examinations was 0.772(P<0.001). As for the 16 patients who also underwent ICA, 15 patients with 22 vessel-areas had hemodynamic stenosis on CT-MPI. Compared with SPECT combined with ICA, the sensitivity, specificity for detecting hemodynamic stenosis were 92.31% (12/13), 71.43% (25/35) for CT-MPI; 100% (13/13), 51.43% (18/35) for CTA and 92.31% (12/13), 82.86% (29/35) for CT-MPI combined with CTA, respectively. Moderate correlation was observed between the combination of CT-MPI and CCTA and reference standard (r=0.690, P<0.001). Conclusion Stress dynamic CT-MPI can detect myocardial perfusion defects and hemodynamic changes and improves the diagnostic ability of functional stenosis of CAD combined with CTA, which can finally achieve the one-stop mode of cardiac CT in CAD. Key words: Myocardial ischemia; Tomography, X-ray computed; Myocardial perfusion imaging; Coronary stenosis