What is a coronary artery aneurysm?
A coronary artery aneurysm is defined as a 50% or greater increase in coronary artery diameter compared with adjacent arterial segments. Coronary artery aneurysms are uncommon lesions, with an overall incidence of 1.6%; incidence among individuals imaged with angiography is as high as 5%. Most commonly, these aneurysms involve the RCA, followed by the LAD artery or circumflex artery. Coronary angiography has been considered as the standard reference technique for diagnosing coronary aneurysms, but it is invasive and expensive. However, if the aneurysm contains substantial thrombus, its true size may be underestimated on catheter angiography. ECG-gated CTA allows a more rapid and accurate delineation of the size and shape of coronary artery aneurysms.