Wells and Sun describe a 78-year-old man with a ruptured thoracic aortic aneurysm.1 Many of the teaching points made are incorrect.
The ruptured aneurysm described is caused by the same pathological process as the abdominal aortic aneurysm (atherosclerosis). The authors fail to assign this etiology and instead discuss aortic dissection, using the two terms interchangeably, as if they are one and the same.
Having incorrectly implied that their patient had aortic dissection, the authors go on to discuss aortic dissection, but fail to mention the universally applied Stanford Classification or the most common cause of dissection in a 78-year-old man, hypertension. Instead, they include Ehlers–Danlos syndrome on their list.
Much of the article describes lower blood pressure in the left arm compared to the right. The blood pressure in one arm can be decreased because of obstruction of inflow by the flap in some patients with dissection, usually type A. However, blood-pressure difference between arms is irrelevant in a patient with a ruptured aneurysm of the descending thoracic aorta. The patient almost certainly had an incidental atherosclerotic stenosis or occlusion of his left subclavian artery.
All mention of aortic dissection should have been deleted from the article, or mentioned only as part of a brief discussion of acute aortic syndrome.2 The authors1 should have stressed the message that chest pain in a patient known to have a large thoracic aneurysm (or with a chest radiograph showing a large aneurysm) should lead to a provisional diagnosis of aneurysm rupture, without waiting for hypotension or pleural effusion to develop. This is similar to abdominal pain in a patient known to have a large abdominal aortic aneurysm.
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