Joseph Luka MD, Presenter: Nothing to Disclose

Linda Le MD, Abstract Co-Author: Nothing to Disclose

Hernan Bazan MD, Abstract Co-Author: Nothing to Disclose

Increasing evidence suggests carotid plaque composition may play an important role in predicting future ischemic events aside from stenosis severity. Soft atheroma has been associated with an increased risk of atherosclerotic plaque rupture. We hypothesized that patients undergoing ‘urgent CEA’ for acute neurological symptoms have a larger amount of soft atheroma compared to patients with asymptomatic high-grade carotid stenosis.

Plaque analysis using the TeraRecon Aquarius software was done on pre-operative CTA images of ‘urgent’ (n=43) and asymptomatic (n=38) CEA patients from 2009-2013. Soft atheroma (0-150 Hounsfield Units, HU), contrast (151-550 HU), and calcium (551-2000 HU) volumes were measured. Non-paired two-tailed t-test was used to determine significance.

The volume of soft atheroma was greater in the ‘urgent’ compared to the asymptomatic group (32.36±2.85% vs. 24.94±2.27%, p = 0.048); no difference was found in the amount of calcium between groups (14.8% vs. 15.63%, p=0.62). The volume of soft atheroma compared to calcified plaque was greater in the ‘urgent’ group (32.36±2.85%, 14.08±2.16%, p < 0.0001) and in the asymptomatic group (24.94±2.27%, 15.64±2.32%, p = 0.005; Figure).

An increased volume of soft atheroma representing a large lipid component is found in patients presenting with acute neurological symptoms, compared to patients with asymptomatic high-grade carotid stenosis. These data suggests that CTA quantification of soft atheroma may be a useful non-invasive marker to assess carotid plaque vulnerability.

Analysis of carotid plaque morphology can have significant implications for the selection of patients who would benefit from carotid revascularization. To study the vulnerable plaque, we determined whether there are differences between urgently performed CEAs for acute neurological symptoms and in patients undergoing CEA for asymptomatic high-grade carotid stenosis. We demonstrate the novel finding that acutely symptomatic carotids have a greater amount of soft atheroma, compared to patients with asymptomatic carotid stenosis. Since the lipid-rich/soft atheroma component of a carotid plaque is likely an important predictor of stroke risk in patients with carotid stenosis, future studies based on this methodology may help to further risk stratify patients with asymptomatic carotid disease at risk for plaque rupture.

Luka, J, Le, L, Bazan, H, Recently Ruptured Carotid Plaques Demonstrate an Increased Content of Soft Atheroma on CTA Compared to Asymptomatic Carotid Lesions.  Radiological Society of North America 2014 Scientific Assembly and Annual Meeting, - ,Chicago IL. http://archive.rsna.org/2014/14006297.html