Imaging coronary and extracoronary atherosclerosis: feasibility and impact of whole-body computed tomography angiography

Abstract

A comprehensive whole-body approach to noninvasive evaluation of coronary and extracoronary vasculature is currently not available. The objective of our study was to assess the potential of 64-slice computed tomography angiography (64-CTA) for whole-body evaluation of atherosclerosis burden. Seventy-eight patients referred for coronary imaging underwent whole-body 64-CTA using an adjusted strategy for the administration of contrast medium with dose-saving algorithms involving ECG modulation and reduced tube voltage. Arterial segments (15 coronary, 32 systemic) were evaluated for significant (> or =50%) steno-occlusive disease while arterovenous density was evaluated at seven extracoronary locations. Homogeneous attenuation (mean 321 +/- 20 HU) was obtained throughout the systemic vasculature. Atherosclerosis was observed in 238/995 (24%) coronary and 368/2441 (15%) systemic segments. Significant stenoses/occlusions were present in 214 (21%)/24 (2.5%) coronary segments while asymptomatic clinically relevant stenoses were present in 49 systemic segments. Sensitivity, specificity, positive and negative predictive values of coronary 64-CTA among 52 patients who also underwent quantitative coronary angiography were 92%, 95%, 81% and 98%, respectively. ECG modulation decreased radiation exposure to 14.1-15.4 mSv per patient. Comprehensive, noninvasive assessment of atherosclerosis can be performed by whole-body 64-CTA and may have a positive impact on secondary prevention.

Clinical impact of computerised tomographic angiography performed for preoperative evaluation before coronary artery bypass grafting

“…For that reason, some radiologists recommend whole-body CT angiography as the standard tool for assessment of the atherosclerosis burden in patients at high risk for cardiovascular diseases [6]. Unlike ultrasonography (US) that has been widely used for screening of the carotid and peripheral arteries before CABG, CT provides surgeon-friendly three-dimensionally reconstructed images not only of the aorta and its major branches but also of bypass conduit candidates such as the ITA, radial artery, gastroepiploic artery and greater saphenous vein.…”

“…For patients with coronary artery disease, CT angiography is now used for several purposes such as screening for coronary artery disease in both outpatient and emergency settings [1][2][3], follow-up after percutaneous intervention [4], and evaluation of bypass graft after surgical revascularisation [5]. Besides the coronary artery, whole-body systemic arteries can be evaluated conveniently with up-to-date 64-slice CT scanner and several contrast-and radiation-saving protocols [6]. Many radiologists consider multi-slice wholebody CT the clinical standard for assessment of atherosclerosis burden in patients at high risk for cardiovascular events.…”

Feasibility of Low-Dose Contrast Medium High Pitch CT Angiography for the Combined Evaluation of Coronary, Head and Neck Arteries

“…The use of noninvasive imaging for direct visualization of atherosclerotic plaques in both coronary and carotid arteries can help to refine risk stratification in certain patients [31]. The comprehensive assessment of coronary and carotid atherosclerosis has also been evaluated using a whole body CTA approach [32], which can be helpful in the detection of multivessel atherosclerosis causing significant vascular stenosis especially in high risk population such as in familial hypercolesterolemia [33]. However, the major drawback have always been high radiation and iodine doses for retrospective ECG-gated coronary CTA with a separate CTA acquisition for extracardiac vasculature.…”

Aortic dual-energy CT angiography with low contrast medium injection rate

“…However, the optimal rate was still controversial to determine. On one hand, the contrast enhancement could be insufficient, if the injection rate was lower than 4 or 5 ml/s [24,25]. But on the other hand, the risk of leaking contrast medium and rupture of vascular wall at intravenous access point was also increased with the increase of injection rate.…”