Abstract
A widened mediastinum is a feature often seen on a plain chest x-ray. When the mediastinum is greater than 6 to 8 cm, depending on which source, it is noted to be wide. A wide mediastinum has many causes which include thoracic aortic aneurysm of the ascending and proximal descending aorta, aortic dissection of ascending and proximal descending aorta, unfolding of the aorta, passing through traumatic aortic ruptura and non-vascular structural causes, such as hilar lymphadenopathy either infectious or malignant (lymphoma, seminoma, thymoma). At elderly, this finding constitutes a real challenge in the emergency room, which must be interpreted in the light of the hemodynamic condition of the patient, taking into account that in the scenario of chronic aortic syndrome it includes aneurysmal dilatations of the aortic root that can be dissected incompletely, presenting with latent intramural hematoma in ascending aorta until aortic tamponade with secondary obstructive shock.