Thoracic aortic aneurysm

Last updated: September 11, 2023

Summarytoggle arrow icon

Thoracic aortic aneurysm (TAA) is the focal dilatation of the thoracic aorta to more than 1.5 times its normal diameter. TAAs are classified by location as affecting the ascending aorta, descending aorta, or aortic arch. Men of advanced age are at a higher risk of forming TAAs; other risk factors include trauma, connective tissue disorders, and hypertension. TAAs are frequently asymptomatic and therefore detected incidentally. If symptomatic, they may manifest with a feeling of pressure in the chest, thoracic back pain, and signs of mediastinal obstruction (e.g., difficulty swallowing). The initial test is often a chest x-ray, which may show a prominent aortic arch. CT with contrast is used to confirm the diagnosis and determine the extent of the aneurysm. Observation, close follow-up, and reduction of cardiovascular risk factors are indicated for small aneurysms whereas pronounced or rapidly expanding aneurysms require surgery. TAA rupture and dissection are life-threatening conditions that require emergency surgical repair to prevent cardiac tamponade, hemothorax, and death.

Definitiontoggle arrow icon

Epidemiologytoggle arrow icon

Epidemiological data refers to the US, unless otherwise specified.

Etiologytoggle arrow icon

Classificationtoggle arrow icon

Pathophysiologytoggle arrow icon


Clinical featurestoggle arrow icon

Aortic aneurysms are mostly asymptomatic or have nonspecific symptoms. They are often discovered incidentally on imaging.

Diagnosticstoggle arrow icon

Imaging [8][9][10][11]

Chest x-ray

CT angiography chest

  • Indications: best confirmatory test for TAAs
    • Abnormal findings on chest x-ray, ultrasound, or echocardiography
    • Interventional planning and follow-up
    • Detailed evaluation of the extent, length, angulation, and diameter of the aneurysm
    • Evaluation of aortic branch involvement
  • Supportive findings [9][10]
    • Dilatation of the aorta [8]
    • Possible mural thrombus (nonenhancing)
    • Possible dissection, perforation, or rupture

Additional imaging

Differential diagnosestoggle arrow icon

The differential diagnoses listed here are not exhaustive.

Treatmenttoggle arrow icon


Invasive treatment: TAA repair [8]

General indications

  • TAA rupture
  • Symptomatic TAA
  • Asymptomatic TAA when size or growth thresholds are passed

Indications for asymptomatic patients

The decision to perform elective TAA repair in asymptomatic patients depends on the size and expansion rate of the aneurysm. In all patients, the risks and benefits of aneurysm resection should be weighed carefully. [6]

Indications for TAA repair in asymptomatic patients [8]
Affected location of the aorta Aortic diameter
Ascending aorta
Aortic arch (isolated)
  • General threshold: ≥ 5.5 cm
  • Growth rate: > 0.5 cm/year
Descending aorta
  • Anatomic requirements for TEVAR are met: ≥ 5.5 cm
  • OSR required: ≥ 6 cm
  • Chronic dissection requiring OSR: ≥ 5.5 cm
  • Increased risk of rupture: Lower thresholds are reasonable.

Procedures [8]

Open surgical repair (OSR) is recommended for patients with TAA of the ascending aorta and aneurysms involving the aortic arch. For patients with descending thoracic or thoracoabdominal aortic aneurysms, thoracic endovascular aneurysm repair (TEVAR) or OSR can be performed.

Open surgical repair (OSR) [8]

Open surgical repair is a major operation with high associated morbidity and mortality. [6]

Thoracic endovascular aneurysm repair (TEVAR) [8]

  • Indications: Degenerative or traumatic descending aortic aneurysms
  • Contraindications
    • Absence of a sufficiently long (2–3 cm) “landing zone” for the stent graft
    • Absence of adequate vascular access sites
  • Procedure: Under fluoroscopic guidance, an expandable stent graft is placed via the femoral or iliac arteries intraluminally at the site of the aneurysm.
  • Complications [8][13]
  • Other: requires lifelong postoperative surveillance

Additional procedures

Concomitant diseases may require additional procedures, e.g., CABG, valve replacement or repair.

Perioperative care

Surveillance after repair [10]

  • CTA chest abdomen pelvis with IV contrast
    • Initially: within the first month then at 3–12 months
    • Then every 6–12 months depending on the stability of findings
  • MRA chest/abdomen/pelvis with IV contrast: in patients with MR-compatible stent grafts (e.g., nitinol)

Conservative management

All patients should receive conservative treatment to reduce the risk of further aneurysm expansion or rupture. Regular aneurysm surveillance via CT or MR is recommended for patients in whom the diameter of the aneurysm has not reached the threshold defined as the indication for repair.

Reduction of cardiovascular risk factors [8]

Aneurysm surveillance

Follow-up frequency for surveillance of thoracic aortic aneurysm or dilatation via CT or MR [8]

Part of the aorta Maximum diameter of the aorta Recommended follow-up interval
Ascending aorta
  • 3.5–4.4 cm
  • 12 months
  • ≥ 4.5 cm
  • 6 months
Aortic arch
  • 3.5–3.9 cm
  • 12 months
  • ≥ 4 cm
  • 6 months
Descending aorta
  • 4–4.9 cm
  • 12 months
  • ≥ 5 cm
  • 6 months

Complicationstoggle arrow icon

We list the most important complications. The selection is not exhaustive.

Thoracic aortic aneurysm rupturetoggle arrow icon

Risk factors [8]

Clinical features [8][11]

It is difficult to tell TAA apart from other causes of acute aortic syndrome using clinical features alone.

More than half of patients with TAA rupture die before reaching the emergency department! [11]

Diagnostics [8][10][11]


Initial stabilization [16]

Interventions such as intubation and opioid analgesia may worsen hypotension!

Patients are at risk of massive transfusion-associated reactions; give blood products in a balanced ratio, use inline blood warming devices, and screen for electrolyte imbalances.

Emergency surgical repair [17]



Acute management checklist for thoracic aortic aneurysmtoggle arrow icon

Referencestoggle arrow icon

  1. Hiratzka LF, Bakris GL, Beckman JA, et al. 2010 ACCF/AHA/AATS/ACR/ASA/SCA/SCAI/SIR/STS/SVM Guidelines for the Diagnosis and Management of Patients With Thoracic Aortic Disease. Circulation. 2010; 121 (13): p.e266-369.doi: 10.1161/CIR.0b013e3181d4739e . | Open in Read by QxMD
  2. Erbel R et al. 2014 ESC Guidelines on the diagnosis and treatment of aortic diseases. Eur Heart J. 2014; 35 (41): p.2873-2926.doi: 10.1093/eurheartj/ehu281 . | Open in Read by QxMD
  3. Bonci G et al. ACR Appropriateness Criteria® Thoracic Aorta Interventional Planning and Follow-Up. J Am Coll Radiol. 2017; 14 (11): p.S570-S583.doi: 10.1016/j.jacr.2017.08.042 . | Open in Read by QxMD
  4. Fukui T. Management of acute aortic dissection and thoracic aortic rupture. J Intensive Care. 2018; 6 (1).doi: 10.1186/s40560-018-0287-7 . | Open in Read by QxMD
  5. Doss M et al. Emergency endovascular interventions for acute thoracic aortic rupture: Four-year follow-up. J Thorac Cardiovasc Surg. 2005; 129 (3): p.645-651.doi: 10.1016/j.jtcvs.2004.09.034 . | Open in Read by QxMD
  6. Munden RF et al. Managing Incidental Findings on Thoracic CT: Mediastinal and Cardiovascular Findings. A White Paper of the ACR Incidental Findings Committee. J Am Coll Radiol. 2018; 15 (8): p.1087-1096.doi: 10.1016/j.jacr.2018.04.029 . | Open in Read by QxMD
  7. Pressler V, Mcnamara JJ. Aneurysm of the thoracic aorta: Review of 260 cases. J Thorac Cardiovasc Surg. 1985; 89 (1): p.50-54.
  8. Hagan PG, Nienaber CA, Isselbacher EM, et al. The International Registry of Acute Aortic Dissection (IRAD): new insights into an old disease.. JAMA. 2000; 283 (7): p.897-903.doi: 10.1001/jama.283.7.897 . | Open in Read by QxMD
  9. Graciaa DS, Mosunjac MB, Workowski KA, Kempker RR. Asymptomatic Cardiovascular Syphilis With Aortic Regurgitation Requiring Surgical Repair in an HIV-Infected Patient. Open Forum Infect Dis. 2017; 4 (4).doi: 10.1093/ofid/ofx198 . | Open in Read by QxMD
  10. Elefteriades JA, Sang A, Kuzmik G, Hornick M. Guilt by association: paradigm for detecting a silent killer (thoracic aortic aneurysm). Open Heart. 2015; 2 (1): p.e000169.doi: 10.1136/openhrt-2014-000169 . | Open in Read by QxMD
  11. Swerdlow NJ et al. Open and Endovascular Management of Aortic Aneurysms. Circ Res. 2019; 124 (4): p.647-661.doi: 10.1161/circresaha.118.313186 . | Open in Read by QxMD
  12. Kumar V, Abbas AK, Aster JC. Robbins & Cotran Pathologic Basis of Disease. Elsevier Saunders ; 2014
  13. Bennett SJ et al. ACR Appropriateness Criteria® Suspected Thoracic Aortic Aneurysm. J Am Coll Radiol. 2018; 15 (5): p.S208-S214.doi: 10.1016/j.jacr.2018.03.031 . | Open in Read by QxMD
  14. Esmaeilzadeh M et al. The role of echocardiography in coronary artery disease and acute myocardial infarction.. J Tehran Heart Cent. 2013; 8 (1): p.1-13.
  15. Abraha I et al. Thoracic stent graft versus surgery for thoracic aneurysm. Cochrane Database Syst Rev. 2016.doi: 10.1002/14651858.cd006796.pub4 . | Open in Read by QxMD
  16. Milleron O et al. Marfan Sartan: a randomized, double-blind, placebo-controlled trial. Eur Heart J. 2015; 36 (32): p.2160-2166.doi: 10.1093/eurheartj/ehv151 . | Open in Read by QxMD
  17. Braverman AC. Medical management of thoracic aortic aneurysm disease. J Thorac Cardiovasc Surg. 2013; 145 (3): p.S2-S6.doi: 10.1016/j.jtcvs.2012.11.062 . | Open in Read by QxMD
  18. Agabegi SS, Agabegi ED. Step-Up To Medicine. Lippincott Williams & Wilkins ; 2013
  19. Thoracic aortic aneurysm. Updated: February 6, 2017. Accessed: February 6, 2017.
  20. Rahimi SA. Abdominal Aortic Aneurysm. In: Rowe VL, Abdominal Aortic Aneurysm. New York, NY: WebMD. Updated: December 19, 2016. Accessed: February 6, 2017.
  21. Elefteriades JA. Natural history of thoracic aortic aneurysms: indications for surgery, and surgical versus nonsurgical risks. Ann Thorac Surg. 2002; 74 (5): p.S1877-1880.
  22. Coady MA, Rizzo JA, Hammond GL, et al. What is the appropriate size criterion for resection of thoracic aortic aneurysms?. J Thorac Cardiovasc Surg. 1997; 113 (3): p.476-491.doi: 10.1016/S0022-5223(97)70360-X . | Open in Read by QxMD
  23. Maleux G, Koolen M, Heye S. Complications after endovascular aneurysm repair. Semin Intervent Radiol. 2009; 26 (1): p.3-9.doi: 10.1055/s-0029-1208377 . | Open in Read by QxMD

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