What is a common risk associated with a thoracic aortic aneurysm?

• A. Myocardial infarction
• B. Pulmonary embolism
• C. Aortic dissection/rupture; risk with hypertension
• D. Stroke

Answer: (C)

The main idea here is that a thoracic aortic aneurysm weakens the wall and increases wall stress, making dissection or rupture the major, most serious risks—especially when hypertension is present. As the aorta enlarges, the radius increases, and according to wall-stress principles, the tendency for the wall to tear or give way rises. An intimal tear can allow blood to dissect between layers of the aorta, which may propagate and compromise blood flow to branches; rupture can cause catastrophic bleeding. Hypertension amplifies this risk by raising the pressure against the already weakened vessel wall, making dissection or rupture more likely. While myocardial infarction, stroke, or pulmonary embolism can occur in patients with cardiovascular disease, they are not the primary, direct complications of an untreated thoracic aortic aneurysm in the same way that dissection or rupture are.