CASE 11073 Published on 14.08.2013

Thoracic aortic aneurysm: case report & literature review

Section

Cardiovascular

Case Type

Clinical Cases

Authors

Sohail Iqbal 1, Zulfiqar Ali 1, Rana T Ahmad 1, Shagufta Jabeen 2, Muhammad Ahsan 3, Muhammad Zubair Hanif 4

1) Stepping Hill Hospital, Stockport, Cardiology;
Email:DRSOHAILIQBAL@YAHOO.COM
2) RMCH, Manchester
3) Salford Royal Hospital, Salford
4) Linyi People's Hospital, Linyi, China
Patient

64 years, female

Categories
Area of Interest Cardiovascular system, Arteries / Aorta ; Imaging Technique Conventional radiography, CT, CT-Angiography
Clinical History
A 64-year-old British white lady presented with sudden onset sharp central chest pain of one hour duration with non-specific electrocardiographic findings and negative Troponin I test. She underwent Computed Tomography Aortography (CTA) and was sent for surgical management.
Imaging Findings
CT Aortography scout film showed widening of the mediastinum with curvilinear peripheral calcification, marginally increased in comparison with 3 years old X-ray chest. Non-contrast enhanced CT (NECT) images confirmed atherosclerotic dilatation of ascending aorta. Calcification was circumferential with no evidence of haematoma or thrombus formation. Axial contrast enhanced CT (CECT) images revealed dilated ascending aorta filling almost all of the mediastinum with some evidence of compression over the surrounding structures. Computer assisted sagittal and coronal reformatted images depicted dilatation of ascending aorta. The whole of the ascending aorta was aneurysmal in fusiform shape, widest in the middle of its length. It was well contained with no evidence of ulceration, leakage, rupture or dissection. Echocardiography was performed and showed competent aortic valve, however, the root of the aorta was also involved and therefore the patient was given an option of surgical correction with possibility of prosthetic valve replacement.
Discussion
Thoracic aortic aneurysm (TAA) is less prevalent (25%) as compared to its abdominal counter-part, however, it can be much more devastating because of enhanced chances of rupture and dissection [1]. An aneurysm is the irreversible blood filled dilatation of a vessel ˃ 50% of its normal size. The shape of the aneurysm can either be saccular - localised outpouching of aortic wall or fusiform - symmetrical, uniform dilatation affecting the entire circumference. Degenerative changes in elastic media of aortic wall are the most common aetiological factor. It includes cystic medial degeneration causing fragmentation of elastic fibres and smooth muscle loss. Incidence of TAA is approximately 5-10 per 100,000 patient years with 3-4% risk in population ˃ 65 years of age [2]. TAA is closely linked to atherosclerosis in approximately 80% of patients and mainly involves all three layers of the vessel forming true aneurysm. Trauma is the second most common cause of TAA resulting mostly in pseudo-aneurysm formation and is seen predominantly in young adults. Inflammatory diseases like Giant cell aortitis, Takayasu aortitis, ankylosing spodylitis, infectious diseases like syphilis and HIV, genetic conditions like Marfan’s Syndrome and Ehler Danlos Syndrome [3]; high blood pressure, coronary artery disease and abdominal aortic aneurysm are all associated with TAA. Patients can present with superior vena cava syndrome, dysphagia, hoarseness or stridor. It can also be diagnosed accidentally on routine chest X-ray and shows widening of mediastinum. CT Aortography is the investigation of choice because of its non-invasiveness & multi-planar reformatting [4]. Non-enhanced CT depicts high attenuation haematoma and helps in differentiation from dissection whereas contrast enhanced CT can show extravasation of contrast. MR aortography is excellent in characterisation of soft tissues, blood and blood products, but is slow and incompatible with pacemakers [5]. Asymptomatic TAA up to 5.5 cm can be managed medically by regular monitoring of size, strict BP control and smoking cessation. Elective repair is recommended at 5.5 cm in the ascending aortic aneurysm, at 6.5 cm in the descending aortic aneurysm in general population and 0.5 cm earlier in patients with familial disorders. Annual growth rate of 1 cm is an independent indicator. Open surgical resection with Dacron Graft replacement, endovascular stenting and hybrid of these two techniques are the treatment options where surgery is to be contemplated [6]. TAA should be suspected at an early stage and managed promptly so as to avoid dreadful complications.
Differential Diagnosis List
Thoracic aortic aneurysm
Mediastinal mass
Aortic dissection
Final Diagnosis
Thoracic aortic aneurysm
Case information
URL: https://www.eurorad.org/case/11073
DOI: 10.1594/EURORAD/CASE.11073
ISSN: 1563-4086