Thoracic aortic aneurysm
Thoracic aortic aneurysm is dilation of the thoracic aorta, often related to hypertension, atherosclerosis, bicuspid aortic valve, or connective tissue disease. Usually asymptomatic, it risks dissection and rupture, so management is blood pressure control, surveillance imaging, and elective repair at size thresholds that are lower in heritable aortopathy.
- Topic reviewThe full article, organized the way the exam asks it.
- ABIM-format MCQsVignettes with an explanation for every wrong answer.
- Key factsThe numbers and thresholds worth memorizing, up front.
- AI tutorMedBrain answers the question you're stuck on.
What this article covers
- Overview
Definition: thoracic aortic aneurysm (TAA) is abnormal dilation of the thoracic aorta, involving the root, ascending aorta, arch, or descending aorta.
- Epidemiology
Ascending aneurysms are often related to bicuspid valves and connective tissue disease.
- Risk factors
Hypertension and atherosclerosis (degenerative and descending disease).
- Pathophysiology
Medial degeneration: loss of elastin and smooth muscle and matrix remodeling weaken the wall.
- Clinical features
Usually asymptomatic. Compressive symptoms: hoarseness, dysphagia, cough, or stridor from local pressure.
- Differential diagnosis
Abdominal aortic aneurysm: aortic dilation below the diaphragm, distinguished by its infrarenal location on cross-sectional imaging rather than a thoracic segment (Abdominal aortic aneurysm).
- Diagnosis
Establish and size with CT or MR angiography, and assess the root with echocardiography: the diagnostic basis is cross-sectional angiography (CT or MRI) accurately measuring the aortic diameter and…
- Management
First-line, control blood pressure and reduce wall stress: a beta-blocker (metoprolol 50 to 100 mg PO daily) to lower heart rate and dP/dt, plus blood pressure control (adding an ARB such as losartan…
- Complications
Aortic dissection and rupture. Aortic regurgitation (root involvement).
- Prognosis
Good with surveillance and timely repair.
- Prevention
Blood pressure control and a beta-blocker to reduce wall stress, targeting blood pressure below 130/80 mmHg and a resting heart rate below 60 to 70 per minute.
Read the whole article
Subscribing to Internal Medicine opens every article, the full question bank and MedBrain, on the web, iPhone and Android.
Related articles
- Abdominal aortic aneurysm
Abdominal aortic aneurysm is focal dilation of the abdominal aorta to 3 cm or more, usually degenerative and often asymptomatic until rupture. Management is risk-factor control and surveillance for small aneurysms and elective repair at 5.5 cm (men) or with rapid growth or symptoms; rupture is a catastrophic emergency.
- Aortic dissection
Aortic dissection is a tear in the aortic intima allowing blood to split the media, creating a false lumen, and is a surgical emergency. Type A (ascending) dissection needs emergency surgery, while type B (descending) is usually managed medically with rapid heart-rate and blood-pressure control; the priority is impulse control with a beta-blocker first.
- Marfan syndrome
Marfan syndrome is an autosomal dominant connective tissue disorder from FBN1 (fibrillin-1) mutations, with skeletal, ocular, and cardiovascular features. The cardiovascular risk drives prognosis: aortic root dilation predisposing to dissection and rupture, managed with beta-blockers or ARBs, activity restriction, surveillance imaging, and prophylactic aortic surgery.
- Aortic regurgitation
Aortic regurgitation is diastolic backflow of blood from the aorta into the left ventricle from valve or aortic root disease. Chronic disease causes volume overload with a wide pulse pressure and a decrescendo diastolic murmur, while acute severe regurgitation is a surgical emergency; severe symptomatic or decompensating disease is treated with valve replacement.