Incremental value of dual-energy CT to coronary CT angiography for the detection of significant coronary stenosis: comparison with quantitative coronary angiography and single photon emission computed tomography

Abstract

To determine the value of dual-energy CT (DECT) and combined information of perfusion and angiography in diagnosing coronary artery disease (CAD), with single photon emission computed tomography (SPECT) and quantitative coronary angiography (QCA) as a reference standard. Thirty-four patients were enrolled in this study. DECT was used as a contrast-enhanced retrospectively ECG-gated scan protocol during the rest state and tubes were set at 140/100 kV. DECT angiography (DE-CTA) and DECT perfusion (DE-CTP) were calculated from two kV images. DE-CTP results were compared with SPECT and DE-CTA with QCA, respectively. The combined DE-CTP with DE-CTA data were compared to QCA in diagnosis of obstructive CAD (stenosis ≥ 50%). DECT showed diagnostic image quality in 31 patients. Using SPECT as a reference, DE-CTP had sensitivity of 68%, specificity of 93%, and sensitivity of 81%, and specificity of 92% for identifying any type of perfusion deficits on the segment- and territory-based analysis, respectively. Using QCA as a reference standard, DE-CTA showed sensitivity of 82%, specificity of 91% and accuracy of 86% for detecting ≥50% coronary stenosis on the vessel-based analysis, whereas the combination of DE-CTA and DE-CTP gave sensitivity of 90%, specificity of 86% and accuracy of 88% for detecting ≥50% coronary stenosis, respectively. Combination of DE-CTP and DE-CTA may improve diagnostic performance compared to CTA alone for the diagnosis of significant coronary stenosis.

Myocardial CT perfusion imaging for ischemia detection

“…Wang et al were among the first to evaluate the incremental value of CTP using DECT over CCTA among 34 patients with known CAD or abnormal SPECT (76). In this study, the combined assessment of CTP plus CCTA (with a sensitivity of 82% and specificity of 91%) achieved improved diagnostic performance compared to the individual use of CCTA or CTP with DECT.…”

Cardiac CT for myocardial ischaemia detection and characterization—comparative analysis

“…Compared with the reference standard of SPECT, Wang et al 86 showed that sensitivity in, specificity of and accuracy of detecting coronary stenosis .50% by addition of DE FP CT increased from 82%, 91% and 86% with cCTA alone to 90%, 86% and 88%, respectively. 88 A recent trial of 50 patients comparing DE CT and SPECT for the detection of obstructive CAD against a gold standard of cMRI reported higher sensitivity (90% vs 85%) and specificity (71% vs 58%) with DE FP CT rather than SPECT (Figures 2 and 3). …”

“…Clinical studies using dual energy first-pass CT Comparisons of DE FP CT to cMRI and PCI, 92 cMRI and SPECT, 53,85 as well as PCI and SPECT 88 have demonstrated its accuracy. Ko et al 92 found that DE FP CT could diagnose reversible ischaemia identified by cMRI with 89% sensitivity, 78% specificity and 82% accuracy.…”

“…In these trials, most perfusion defects on rest and stress SPECT studies were detected from rest DE FP CT series. 53,88 Although DE FP CT has often been performed as part of a three-part acquisition series, the additional diagnostic value of each series has not been conclusively investigated. Likewise, in SE FP CT , a recent study has proposed that delayed enhancement might not be necessary in all cases, reducing patient radiation exposure.…”

Clinical Impact of Rest Dual–energy Computed Tomography Myocardial Perfusion in Patients with Coronary Artery Disease

“…As rest DECT-P is derived from the same datasets as standard cCTA, it requires no additional contrast media, radiation exposure, or stress agents, which represents a substantial advantage, when compared to stress protocols. Studies have compared DECT-P with single-photon emission computed tomography (SPECT), magnetic resonance imaging (MRI), and ICA in rest or rest-stress acquisition with first or second generation dual-source scanners and found an incremental value over cCTA alone (3)(4)(5)(6). However, the data for rest-only acquisition in DECT-P is rather sparse and needs further investigation regarding the clinical utility and its effect on patient care in a real clinical setting.…”