Chest pain

Our appreciation is extended to Dr. Jared Bailey, Indiana University Department of Radiology, for contributing this case.

Chest pain

Chest pain

• Ascending aortic atheroma / thrombus
• Ascending aortic dissection
• Motion artifact
• Aortitis

Chest pain

An aortic atheroma is a thrombus. It is thought that aortic atheromas most commonly occur as a progression of atherosclerotic disease where intimal damage has occurred either acutely from trauma or much more commonly from atherosclerotic progression. Atheromas can occur anywhere within the aorta or vasculature. They can be either freely mobile or fixed in position. Patients can present asymptomatically or with symptoms of distal embolic events. Ascending aortic atheromas are a significant risk factor for stroke. Therefore particular attention should be given to ascending aortic atheromas because of their potential to cause cerebral vascular events.

The best well described classification for aortic arch atheromas is the Montgomery system. I- Normal or mild thickening of the intima. II- Extensive intimal thickening. III- Atheroma <5mm. IV- Atheroma >5mm, and V- Mobile lesion.

CT is described as being excellent in defining intimal wall irregularity and the size of atheromas. CT is however poor at distinguishing fixed from freely mobile clot, which can dramatically alter management. Even small atheromas that are freely mobile are often treated surgically due to the potential high risk of distal embolic events. Some literature describes trans esophageal echo as being superior to CT in defining whether clots are fixed or mobile. Cardiac gated CT's can be helpful in eliminating pulsation artifact and differentiating atheromas from dissection flaps.

Treatment varies by location of the atheroma, patient status, and institution. Our patient was treated at a large cardiovascular center and on TEE was shown to have a class V freely mobile ascending aortic atheroma. He was treated surgically on cardiac bypass and underwent open resection and placement of a focal aortic arch graft at the site of the intimal injury. Other treatment options include systemic anticoagulation, and endovascular therapy. Non-surgical treatment is often reserved for non-mobile small atheromas. Optimal treatment is not well defined in the literature.

• CT: Arterial timing is critical and will show a linear intraluminal filling defect. The atheroma can have various shapes and sizes and can adhere to the wall of the vessel or project into the lumen. Again CT gating of atheromas in the chest can be helpful to distinguish from a possible dissection flap.
• US: Again some literature describes TEE as the modality of choice to determine the presence of freely mobile atheromas. Clot would appear as echogenic debris with an anechoic vessel.
• Angiography: Arterial angiography can be used to evaluate for atheromas, however the concern exists for possible disruption of mobile atheromas causing distal embolization. Literature does describe endovascular treatment of non-mobile descending aortic atheromas.

Key points:

• Atheromas of the ascending aorta appear as irregular shaped intraluminal filling defects.
• Appropriately gated CTA is excellent at identifying atheromas, however limitations include the ability to differentiate fixed from freely mobile plaques. TEE is helpful for this differentiation.
• Ascending aortic atheromas are a significant risk factors for stroke.
• Treatment is not well defined however it appears that the location, size, and nature (freely mobile or fixed) of the atheroma should determine treatment whether surgical or medical.

1. Tullio MR, Sacco RL, et al. Aortic atheroma morphology and the risk of ischemic stroke in a multiethnic population. American Heart. 2000;139(2).
2. Souvik S, Oppenheimer S, et al. Risk factors for progression of aortic atheroma in stroke and transient ischemic attack patients. Stroke 2002. 33:933-935.
3. Statdx.com 2005-2010.

Chest pain