Dual-energy CT of the heart for diagnosing coronary artery stenosis and myocardial ischemia-initial experience

Abstract

We aimed to evaluate the feasibility of diagnosing coronary stenosis and myocardial ischemia with a single dual-energy CT (DECT) acquisition. Thirty-five patients underwent contrast-enhanced, ECG-gated DECT of the heart while independently operating the two tubes of a dual-source CT system at high- and low-energy X-ray spectra. From the same raw data, coronary CTA (cCTA) studies were reconstructed for stenosis detection, and the myocardial blood-pool was analyzed by determining the tissue iodine content. Two independent observers analyzed all studies for stenosis and myocardial blood-pool deficits. Results were correlated with SPECT, coronary catheterization and cCTA on a segmental basis. cCTA had 98% sensitivity, 88% specificity and 92% accuracy for detection of >50% stenosis. DECT detected myocardial ischemia with 84% sensitivity, 94% specificity and 92% accuracy. Our initial experience may warrant further exploration of DECT as a possibly feasible single imaging investigation for the comprehensive diagnosis of coronary stenosis and myocardial ischemia.

Stress Dual-Energy Computed Tomography-Myocardial Perfusion Imaging to Identify Coronary Artery Stenoses Causing Ischemia: A Direct Comparison between Invasive Coronary Angiography and Cardiac Magnetic Resonance-Myocardial Perfusion Imaging

“…Mapping the iodine distribution within the left ventricular myocardium is possible with DECT. Accordingly, DECT-based iodine maps highlight areas of decreased iodine in the left ventricular myocardium [15][16][17]. The present results are in accordance with our previous stress DECT-MPI studies.…”

“…Myocardial perfusion datasets were semi-quantitatively evaluated using a 0.75-mm slice thickness and a 0.4-mm slice increment using a dedicated dual-energy convolution kernel (D26f) at the mid-diastolic phase [15]. DECT-based colorcoded iodine distribution maps were superimposed onto grayscale multiplanar reformats of the left ventricular myocardium in the short-and long-axis views (5-mm slice thickness and no intersection gap) using the dual-energy image post-processing software application of the Syngo-Multi-Modality Workplace (syngoDualEnergy; Siemens, Forchheim, Germany).…”

“…Dual-energy computed tomography (DECT) has recently emerged as a novel method for assessing myocardial perfusion. Based on the specific absorption characteristics of iodine for different X-ray energies, DECT allows mapping of intra-myocardial iodine extent and distribution, and small sample studies have demonstrated the feasibility of this technique to detect myocardial perfusion deficits [15][16][17]. However, large-scale studies examining stress DECT-MPI are lacking [18,19].…”

Dose levels at coronary CT angiography—a comparison of Dual Energy-, Dual Source- and 16-slice CT

“…In addition there is evidence that suggests the usefulness of DECT for comprehensive imaging of coronary artery disease and the evaluation of myocardial perfusion [12,13].…”

Infarct characterization using CT

“…The presence of a myocardial hypo-enhancement region at rest on CCT has a sensitivity and specificity of around 90% to identify patients with a MI (Figures 5-7) (89,90). Rest dual energy CT provided comprehensive CAD imaging and identified perfusion defects in 90% of cases compared to SPECT (60).…”