In detecting coronary artery disease (CAD), fusion images obtained by combining myocardial perfusion imaging (MPI) and computed tomography coronary angiography (CTCA) have shown a higher accuracy and clinical usefulness than these modalities used separately or a simple comparison of individual images. However, the clinical use of fusion images has been restricted by the necessity of obtaining images with an integral type device or with devices made by the same manufacturer. Thus, we evaluated the detection of hemodynamically significant CAD by fusion images created with a newly developed general-purpose application that can be used with any type of device.Methods and results
In 49 patients, MPI during exercise and at rest and CTCA were obtained separately and combined into fusion images using the new application. As the reference standard, a comparative interpretation of MPI and the conventional coronary arteriography (CAG) was adopted. Hemodynamically significant CAD were diagnosed when MPI showed a reversible perfusion defect in a region with greater than 50% luminal stenosis on CAG. The capability of fusion images to detect CAD was compared with that of CTCA images alone. Fusion images showed a higher ability to detect CAD (sensitivity 80%, specificity 94%, positive predictive value 77%, and negative predictive value 95%) than CTCA alone (77, 77, 46, and 93%, respectively; fusion vs. CTCA: specificity P=0.0002, positive predictive value P=0.0001).Conclusion
Fusion images obtained with a general-purpose application were superior to CTCA images alone for detecting hemodynamically significant CAD.