Computed Tomographic Angiography (CTA) of the Coronary, Aorta, Visceral, and Lower Extremity Arteries

X-ray computed tomography angiography (CTA) is an ideal method for imaging the cardiovascular system given its potential for acquiring cross-sectional images, differentiating tissues, and obtaining reliable three-dimensional anatomical measurements. CTA performed with modern multi-slice systems permits rapid acquisition of vascular studies with high spatial resolution. CTA permits a noninvasive assessment of the coronary anatomy, is capable of quantifying coronary calcium in atherosclerotic plaques, and excludes the presence of severe stenosis of native coronary arteries and bypass grafts with reasonably high negative predictive accuracy. CTA has largely replaced ventilation/perfusion (V/Q) testing in the acute setting given its higher acquisition speed, lower cost, and higher diagnostic accuracy for the detection of large proximal emboli. CTA is ideal for evaluating pathologies of the thoracic aorta that demand rapid and accurate diagnosis and/or precise anatomical measurements. In patients undergoing endovascular repair, CTA permits topographic planning of endovascular prosthesis implantation, both in descending thoracic aorta and abdominal aorta. CTA is standard in the follow-up phase for identifying false lumen thrombosis and detecting the presence of endoleaks or aneurysm re-expansion. CTA is an important noninvasive method for the diagnosis of renal artery stenosis and for evaluation after revascularization.