Abdominal & Thoracic Aortic Aneurysms

Monitoring and treatment are guided by the aneurysm's location, size, rate of growth, shape and the patient's overall health. Timely specialist assessment matters because a large or rapidly expanding aneurysm carries a greater risk of rupture.

An aneurysm forms when a weakened segment of the aortic wall gradually stretches. Abdominal aneurysms occur below the diaphragm, thoracic aneurysms arise within the chest, and some extend across more than one aortic segment. Because most cause no symptoms, decisions rest largely on careful measurement over time rather than on how a person feels.

What is an abdominal aortic aneurysm?

An abdominal aortic aneurysm, commonly called an AAA, develops below the diaphragm and most often below the arteries supplying the kidneys. It may extend into the iliac arteries within the pelvis.

Most AAAs are discovered incidentally during an ultrasound or CT scan. Some are detected through screening or investigation of a pulsating sensation or unexplained abdominal or back discomfort.

What is a thoracic aortic aneurysm?

A thoracic aortic aneurysm forms within the chest and may affect the ascending aorta, aortic arch or descending thoracic aorta. Its causes and treatment can differ from those of an abdominal aneurysm.

Some thoracic aneurysms are associated with longstanding high blood pressure, atherosclerosis, inherited connective tissue disorders, bicuspid aortic valve disease or previous aortic dissection.

Risk factors

Risk increases with age, smoking, high blood pressure, atherosclerosis and a family history of aortic aneurysm. Men are more commonly affected by AAA, although aneurysms in women may rupture at a smaller diameter.

A family history is particularly important. First-degree relatives may be advised to discuss screening with their GP or vascular specialist.

Possible symptoms

Most aortic aneurysms are silent and are discovered on imaging performed for another reason. When symptoms occur, they may include persistent abdominal, back, chest or flank pain, a pulsating sensation in the abdomen, hoarseness, difficulty swallowing or shortness of breath, depending on the aneurysm's location.

These symptoms have many possible causes and do not necessarily indicate an aneurysm, but persistent or unexplained symptoms warrant medical assessment.

When to seek emergency care

Sudden severe chest, back or abdominal pain, collapse, fainting, clammy skin or rapidly worsening weakness may indicate rupture or acute aortic disease. Call Triple Zero (000) immediately.

A ruptured aortic aneurysm is a life-threatening emergency requiring urgent hospital treatment.

Ultrasound is the usual tool for measuring abdominal aneurysms and for surveillance, because it is accurate for size and involves no radiation. CT angiography maps the entire aorta and its branch vessels and is generally required when repair is being planned. Echocardiography and MR angiography help in selected patients, particularly when the aortic root or ascending aorta is involved.

The surgeon also reviews blood pressure control, smoking history, family history of aneurysm, kidney function, previous operations and overall cardiovascular fitness, because these influence both rupture risk and the safety of any repair.

Small aneurysms are generally monitored with scheduled imaging while cardiovascular risk factors are treated. Repair is considered when the estimated risk of rupture, based on size, growth rate and individual factors, begins to outweigh the risks of intervention.

The main repair options are open surgical replacement of the diseased segment and endovascular repair with a stent graft. Choosing between them depends on the aneurysm's anatomy, its relationship to branch arteries, the patient's fitness for open surgery and the expected durability of each approach. A stent graft is not automatically the better choice simply because it is less invasive.

Reducing cardiovascular risk

Blood pressure control, smoking cessation, cholesterol management and treatment of other cardiovascular risk factors are important for overall vascular health. These measures do not remove an aneurysm, but they may reduce additional cardiovascular risk.

Endovascular aneurysm repair

Endovascular aneurysm repair uses a stent graft introduced through the arteries, usually from the groin, to create a new channel for blood and reduce pressure on the aneurysm wall. EVAR treats suitable abdominal aneurysms, while TEVAR is used for selected thoracic aneurysms.

Suitability depends on the anatomy of the aorta and its branches. Lifelong imaging surveillance is generally required after endovascular repair.

Open aneurysm repair

Open repair involves replacing the affected section of aorta with a surgical graft. It may be recommended when anatomy is unsuitable for endovascular repair, when durability is a priority or when other aortic disease must be treated at the same time.

Recovery is usually longer than after endovascular treatment, but open repair remains an important and durable option for appropriately selected patients.

How is treatment selected?

The decision considers aneurysm size and growth, symptoms, anatomy, age, general health, previous operations and the relative risks of continued monitoring, endovascular repair and open surgery.

Complex cases may require multidisciplinary planning and collaboration with cardiac, cardiothoracic or other specialist teams.

Rupture causes life-threatening internal bleeding. Repair also carries risks that vary with anatomy and general health, including bleeding, kidney injury, heart or lung complications, stroke, reduced blood flow to organs or limbs, infection and the possibility of further procedures.

After endovascular repair in particular, lifelong imaging follow-up checks that the stent graft continues to exclude the aneurysm. Patients under surveillance should attend scans as scheduled and report new abdominal, back or chest pain promptly.

Aneurysm surveillance

Smaller aneurysms may be monitored with scheduled imaging. The interval between scans depends on aneurysm size, growth and individual risk factors.

Surveillance is only effective when follow-up imaging occurs as recommended. Patients should advise the clinic if they develop new symptoms between appointments.

Useful questions for an aneurysm consultation include how large the aneurysm is, whether it has grown since the last scan, and at what point repair would be recommended for someone in your situation.

You may also want to ask how often surveillance scans are needed, what warning symptoms should prompt urgent review, whether relatives should consider screening, and how endovascular and open repair would each apply to your anatomy. Bring your medication list and any previous imaging reports.

Two people with aneurysms of similar size can reasonably receive different advice, because growth rate, aortic shape, fitness for surgery and personal priorities all affect the balance between surveillance and repair. Scan measurements are a starting point for that discussion, not a verdict on their own. Your surgeon will talk through the options so the decision is made together.

Yarra Vascular Surgeons manages aortic aneurysms across the whole pathway, from first detection and surveillance through to open and endovascular repair. Imaging-based measurement and structured follow-up underpin every recommendation, and complex thoracic or multi-segment disease is planned collaboratively with other specialist teams.

Aortic aneurysms require careful measurement, risk assessment and reliable surveillance, because treatment decisions depend on location, size, growth and individual anatomy. Yarra Vascular Surgeons combines vascular imaging with experience in open and endovascular aneurysm repair, allowing patients to receive a considered recommendation based on rupture risk, procedural suitability and long-term durability.