Name : Hamid Reza
Family :Pour Aliakbar
Affiliation : Radiology Department,ShahidRajaeeHospital,TUMS
Academic Degree: Assistant Professor of Radiology
Resident : Reza Shahsavari
Gender : Male
Age : 30
30 years old man with past medical history of Coarctation of the aorta that was repaired presented whit sudden and radiating chest pain.
Axial multislice CT scan shows aneurysm of the descending aorta after previous repair of aortic coarctation,penetrating (leaking) descending aortic aneurysm, high-density pleural fluid consistent with acute hemorrhage, aneurysmal dilation of the left subclavian artery and collapse of the left lung.
Leaking thoracic aortic aneurysm
Discussion (Related Text)
Coarctation of the aorta is an abnormal narrowing of thedescending aorta. It most commonly manifests as a focal area of narrowing distal to the left subclavian artery. Treatment for coarctation is either open surgical repair or catheter interventions, including angioplasty and stent implantation. The choice of procedure depends on the site and extent of the coarctation and the patient's age. After surgical repair or post balloon angioplasty, CT or MR can be used to demonstrate complications, such as residual stenosis or restenosis, aneurysm formation, and dissection. The prevalence of recoarctation is between 3% and 41 % and is associated with smallerpatient size or younger age at operation and the presence of associated transverse arch hypoplasia. The frequency of aneurysms is reported to be 5% to 9% after end-to-end anastomosis, 33% to 51% after Dacron patch aortoplasty, and 4% to 12% after angioplasty A true thoracic aortic aneurysm involves all components of the vessel wall. The morphologic subtypes of aneurysm are saccular, fusiform, dissecting, and false.Acute aneurysmal rupture is an infrequent occurrence.Thoracic aortic aneurysms are most commonly located within the descending aorta at the level of the ligamentum arteriosum, just distal to the origin of the subclavian artery. They are less commonly found within the descending aorta at the level of the aortic hiatus of the diaphragm. The aorticarch is the next most common site, followed by the ascending aorta. The presence of a thoracic aortic aneurysm should not be concluded solely from the measurement of aortic circumference. The circumference of the aorta varies significantly according to the size, sex, and age of the patient and the width of the thoracic vertebral body. For practical purposes, the descending aorta should never be larger than the ascending aorta at a given scan level, and the ratio of the coronal diameter of the ascending aorta to that of the descending aorta should be about 1.5:1 The maximum diameter of the aneurysm correlates well with the incidence of rupture. Up to 50% of deaths from thoracic aortic aneurysms are caused by rupture. For aneurysms less than 5 cm in diameter, the incidence of rupture is 2%; for aneurysms larger than 10 cm, the incidence of rupture is greater than 50%. A leaking or ruptured thoracic aortic aneurysm creates extensive tissue density from mediastinal hematoma and, occasionally, a left pleural effusion. Rarely, contrast material can be seen beyond the confines of the aortic wall on bolus-injected, contrastenhanced CT scans.
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