Who should be screened for AAA?

Men aged 65–75 who have ever smoked are the primary screening group recommended by USPSTF and supported by most vascular surgery guidelines. Men aged 65 and over with other risk factors (family history, hypertension, established cardiovascular disease) may also benefit from a one-time screening ultrasound, discussed with their GP. Women are at substantially lower overall risk; those aged 65–75 who have ever smoked may benefit from an individual discussion with their clinician.

What does AAA screening involve?

AAA screening uses abdominal ultrasound — the same technology used in pregnancy scans. A small probe is placed on the abdomen with gel, and sound waves create images of the aorta. The test takes approximately 10–15 minutes, is painless, involves no radiation, and requires no preparation beyond sometimes fasting for 4–6 hours beforehand to improve image quality. The diameter of the aorta is measured, and the result is classified as normal, borderline, or aneurysmal.

What happens if an AAA is found?

The next step depends on the size of the aneurysm. Small AAAs (3.0–4.4 cm) are monitored with repeat ultrasound every 12 months. Medium AAAs (4.5–5.4 cm) require more frequent surveillance (every 3–6 months) and referral to a vascular surgeon for discussion. Large AAAs (5.5 cm or greater in men; 5.0 cm or greater in women) typically warrant consideration for elective surgical repair. Lifestyle changes — especially smoking cessation and blood pressure control — are important at all sizes.

Is there a national AAA screening program in Australia?

No. As of 2026, Australia does not have a national organised AAA screening program. The UK has had the NHS Abdominal Aortic Aneurysm Screening Programme since 2009, inviting all men for a single ultrasound at age 65. In Australia, AAA screening is opportunistic — it must be requested by a GP or initiated by the patient. Some state-based vascular services and private radiology providers offer screening ultrasound, but there is no Medicare-funded national program.

AAAs do not resolve spontaneously. Small aneurysms are managed conservatively — monitoring and risk factor modification — to slow growth. Large aneurysms that meet size thresholds or grow rapidly are treated with elective surgical repair: either endovascular repair (EVAR) or open surgery. Repair prevents rupture. It does not restore the aorta to normal, but it removes the risk of catastrophic bleeding. Without repair, a large AAA (≥5.5 cm) carries an annual rupture risk of approximately 10–25%.

Abdominal Aortic Aneurysm Screening: Who Should Be Tested and When

What Is an Abdominal Aortic Aneurysm?

The aorta is the largest artery in the body — a vessel roughly the width of a garden hose that carries oxygenated blood from the heart, down through the chest and abdomen, before dividing into the arteries supplying the legs. The section passing through the abdomen — the abdominal aorta — is the most common site for a type of vascular problem called an aneurysm.

An aneurysm is a localised dilation (widening or bulging) of a blood vessel beyond its normal diameter. The normal abdominal aorta is approximately 1.5–2.0 cm in diameter in adults. An abdominal aortic aneurysm (AAA) is diagnosed when the aortic diameter reaches 3 cm or more.

Most AAAs:

Cause no symptoms — they are silent until they rupture or are found incidentally during imaging for another reason
Grow slowly — typically less than 1 cm per year in small aneurysms
Are found in the infrarenal segment of the aorta (below the arteries supplying the kidneys)
Are more common in men and in people who smoke or have smoked

The clinical danger is rupture: when the wall of the aneurysm gives way, massive haemorrhage occurs into the retroperitoneal space or abdominal cavity. Ruptured AAA carries a mortality of approximately 80–90% — most patients die before reaching hospital, or before emergency surgery can be completed. Elective repair, by contrast, is performed safely with a mortality of under 2% in specialist vascular surgery units.

This is the core argument for screening: identifying aneurysms before they rupture allows elective, planned treatment with dramatically lower risk than emergency repair of a ruptured aneurysm.

Key Points

An AAA is a widening of the abdominal aorta to 3 cm or more; a diameter of 5.5 cm (men) or 5.0 cm (women) typically triggers consideration for elective surgical repair.
Ruptured AAA carries approximately 80–90% mortality; elective repair carries less than 2% mortality in specialist vascular units.
Abdominal ultrasound is the screening test — painless, accurate, and without radiation.
USPSTF (2019) recommends a one-time ultrasound screening for men aged 65–75 who have ever smoked.
The UK NHS has screened all men at age 65 since 2009, substantially reducing AAA rupture deaths.
Australia has no national AAA screening program as of 2026; screening is opportunistic through a GP referral.
Risk factors include male sex, age 65 and over, ever-smoking, family history, hypertension, high cholesterol, and established cardiovascular disease.
Smoking cessation is the single most effective lifestyle intervention for slowing AAA growth.
Small and medium AAAs are managed with surveillance; large AAAs are referred for vascular surgery assessment.
Women are at substantially lower overall risk but may benefit from selective screening if they have smoked and have additional risk factors.

Why Rupture Is So Dangerous

When an AAA ruptures, the consequences are immediate and severe:

The aortic wall tears, releasing blood under high arterial pressure into the retroperitoneal space or abdominal cavity
Blood pressure drops rapidly; collapse and loss of consciousness can follow within minutes
Emergency surgical repair requires immediate access to a vascular surgery centre with operating theatre capacity
Even with emergency surgery, mortality from ruptured AAA is approximately 40–50% for patients who reach theatre — and when pre-hospital deaths are included, overall mortality exceeds 80%
By contrast, planned elective repair carries operative mortality of under 2% in specialist centres

The size of an aneurysm predicts its annual rupture risk:

AAA Size	Annual Rupture Risk
3.0–4.4 cm (small)	<1% per year
4.5–5.4 cm (medium)	1–5% per year
5.5–5.9 cm	10–15% per year
6.0–6.9 cm	20–25% per year
≥7.0 cm	30–50% per year

This size-risk relationship explains why the threshold for elective repair is set at 5.5 cm in men and 5.0 cm in women — the annual rupture risk at this size becomes sufficient to justify surgical intervention, even accounting for the risks of elective surgery itself.

The Screening Test: Abdominal Ultrasound

Abdominal ultrasound is the standard and only recommended screening modality for AAA. It is:

Painless — a probe is placed on the skin surface with gel
Quick — approximately 10–15 minutes
Accurate — sensitivity and specificity for AAA detection exceed 95%
Without radiation — uses sound waves, not X-rays
Inexpensive relative to other vascular imaging modalities (CT, MRI)

Preparation: You may be asked to fast for 4–6 hours beforehand. Bowel gas can obstruct the view of the aorta; fasting improves image quality. Water is usually permitted.

The sonographer places the ultrasound probe over your upper abdomen and traces the aorta from just below the ribcage to where it divides at the level of the navel. The maximum diameter is measured at the widest point. Results are typically available immediately or within a short time via a written radiology report sent to your referring GP.

A one-time screening test is sufficient for most people with an initially normal result (aorta below 3 cm), as the risk of subsequently developing a significant AAA is very low.

Who Should Be Screened

Primary Recommendation Group

Men aged 65–75 who have ever smoked (defined as having smoked 100 or more cigarettes in their lifetime) are the group for whom the evidence most clearly supports a single ultrasound screening.

USPSTF (2019): Grade B recommendation — one-time abdominal ultrasound screening for men aged 65–75 who have ever smoked
NHS (UK): All men are invited for a single abdominal ultrasound at age 65 as part of the national AAA Screening Programme (regardless of smoking history)
Society for Vascular Surgery (US): Screening recommended for all men aged 65 or over who have ever smoked; and for men and women aged 75 or over with a history of peripheral artery disease or coronary artery disease combined with smoking history

Other Higher-Risk Groups

Group	Recommendation
Men aged 65+ with family history of AAA (first-degree relative with AAA)	Discuss screening with GP — risk is approximately 2× higher
Men aged 65+ with multiple cardiovascular risk factors (hypertension, established coronary or peripheral artery disease, atherosclerosis)	Consider screening; discuss with GP or cardiologist
Women aged 65–75 who have ever smoked	USPSTF: insufficient evidence to routinely recommend or advise against; individual clinical discussion warranted given elevated risk
Women with a first-degree family history of AAA	Individual discussion warranted; screening may be appropriate
Siblings of people with known AAA	Brothers of affected individuals have substantially elevated prevalence; discuss early screening

Who Does Not Require Routine Screening

Never-smoker men aged 65–75 with no family history or significant cardiovascular risk — the prevalence of AAA in this group is substantially lower
Women who have never smoked and have no family history — prevalence is low
People younger than 65 without high-risk features
People with a previously normal screening result (aorta below 3 cm) — repeat screening is generally not recommended

Risk Factors

Understanding risk factors clarifies who benefits most from screening.

Strongly Elevated Risk

Male sex — men are 4–6× more likely to develop AAA than women; most guideline recommendations are targeted specifically at men
Ever-smoking — the strongest modifiable risk factor; smoking history increases AAA risk 3–5× and is independently associated with faster aneurysm growth and larger size at presentation
Age 65 and above — prevalence rises markedly from the mid-60s onward
Family history — a first-degree relative with AAA increases individual risk approximately twofold; sibling history is particularly relevant

Additional Risk Factors

Hypertension (high blood pressure)
High cholesterol and hyperlipidaemia
Established cardiovascular disease — coronary artery disease, peripheral artery disease, or prior stroke
Atherosclerosis (arterial wall disease)
White or European ancestry (higher prevalence than other ethnic groups in most epidemiological studies)

Lower Risk (Relative)

Female sex
Non-smoking or minimal smoking history
Younger age
Asian or African ancestry (lower prevalence in most population studies)

Note on diabetes: Diabetes mellitus is paradoxically associated with a lower risk of AAA compared with people of equivalent cardiovascular risk without diabetes. The mechanism is not fully established. This is an exception to the general pattern in which cardiovascular risk factors increase AAA risk.

Understanding Your Results

The ultrasound report will state the measured maximum diameter of your aorta. Findings are categorised as follows:

Surveillance and Management by AAA Size

Category	Diameter	Annual Rupture Risk	Recommended Action
Normal	<3.0 cm	Negligible	No further screening in most guidelines
Small AAA	3.0–4.4 cm	<1% per year	Surveillance ultrasound every 12 months; risk factor modification
Medium AAA	4.5–5.4 cm	1–5% per year	Surveillance every 3–6 months; vascular surgery referral for discussion
Large AAA (men)	≥5.5 cm	10–25%+ per year	Prompt vascular surgery referral; consider elective repair
Large AAA (women)	≥5.0 cm	Elevated	Prompt vascular surgery referral
Rapid growth	≥1 cm increase in 12 months	Elevated regardless of size	Vascular surgery referral

When a large or rapidly growing AAA is detected, surgical repair is discussed with a vascular surgeon. This is an elective decision at a planned time — it is not an emergency. You and your surgeon will discuss the approach, timing, and your overall health status.

Treatment Options

When an AAA reaches the threshold for repair or grows rapidly, two main surgical approaches are available:

Endovascular Aneurysm Repair (EVAR)

EVAR has become the most widely used treatment for AAA in patients with suitable anatomy.

A flexible stent-graft is inserted through the femoral arteries in the groins, guided by X-ray imaging, and deployed inside the aorta to line the aneurysm sac
Blood is redirected through the graft; the aneurysm sac is excluded from arterial pressure and gradually shrinks
Minimally invasive — no large abdominal incision is required
General or regional anaesthesia; hospital stay typically 1–3 days
Requires long-term surveillance imaging (annual CT or ultrasound) to check for endoleaks — small leaks of blood around the graft
Suitable for most anatomically eligible patients; aortic anatomy determines whether EVAR is technically feasible

Open Surgical Repair

Open repair involves a laparotomy (abdominal incision), clamping the aorta above and below the aneurysm, and sewing in a synthetic graft.

More invasive with a longer recovery (typically several weeks)
Generally preferred for patients in whom EVAR is anatomically unsuitable, or younger patients in whom long-term graft durability over decades is a consideration
Operative mortality in specialist centres: approximately 1–5% for elective cases
After successful repair, ongoing surveillance imaging is not routinely required — the open graft does not need the same monitoring as EVAR

Conservative Management (Small to Medium AAAs)

For aneurysms not yet meeting repair thresholds, management focuses on slowing growth and reducing overall cardiovascular risk:

Smoking cessation — the most important single intervention; smoking accelerates AAA growth and significantly increases rupture risk. Quitting substantially slows progression.
Blood pressure control — hypertension increases aortic wall stress and rupture risk; target typically below 130/80 mmHg
Statin therapy — strong evidence for cardiovascular risk reduction broadly; the evidence for slowing AAA growth specifically is less definitive, but statins are indicated in most people with AAA on cardiovascular grounds
Regular surveillance ultrasound — to monitor size and detect growth that warrants earlier referral
Regular GP and vascular surgery review as appropriate to the aneurysm size

Life After Repair

After successful EVAR or open surgical repair:

The risk of aortic rupture is essentially eliminated
Long-term cardiovascular risk management continues — smoking cessation, blood pressure, cholesterol, and exercise
EVAR patients require ongoing imaging surveillance (annual CT or ultrasound) to monitor graft integrity and check for endoleaks
Open repair patients generally do not require routine post-operative graft surveillance imaging after confirming a good early result
Overall life expectancy after successful elective AAA repair reflects the patient’s underlying cardiovascular risk profile — repair removes the AAA risk but does not alter atherosclerotic disease elsewhere
Erectile function may be affected after open repair due to proximity to pelvic nerves; EVAR generally has lower rates of this complication

Shared Decision-Making

For individuals who meet eligibility criteria, the choice to have screening is generally straightforward — the test is non-invasive, quick, and accurate, and the consequences of missing a large undetected AAA can be catastrophic. However, context matters:

If serious comorbidities would make surgical repair unsafe, the value of identifying an AAA is reduced. A person who could not safely undergo any form of surgery may reasonably discuss whether screening is appropriate for them.
A screening result is not a commitment to intervention. Finding a small AAA does not mean immediate surgery — most small and medium aneurysms are monitored for years before meeting repair thresholds.
Personal values regarding surveillance, anxiety, and the preference for knowing a diagnosis before symptoms arise are all relevant.

Discuss the decision with your GP, who can clarify your individual risk, explain what a positive result would mean in practice, and facilitate referral to a vascular service if needed.

Australian Context

As of June 2026, Australia has no national organised AAA screening program. There is no Medicare-funded population screening for AAA.

This contrasts with the United Kingdom, where the NHS Abdominal Aortic Aneurysm Screening Programme has invited all men for a single ultrasound at age 65 since 2009. UK data demonstrate a substantial reduction in AAA rupture deaths in men who participated in the programme compared with historical rates.

Guideline Positions in Australia

Heart Foundation of Australia: Acknowledges AAA as a significant cardiovascular condition and supports risk factor reduction (smoking cessation, blood pressure, lipid management) as primary prevention. Supports individual clinical assessment for high-risk groups.
RACGP (Red Book): Recommends clinicians consider AAA screening for at-risk men (aged 65–75, ever-smokers) and supports an individual discussion about screening in the absence of a national programme.
Vascular Society of Australia and New Zealand (VSANZ): Has advocated for a national AAA screening programme consistent with international evidence, and supports one-time ultrasound for men aged 65–75 who have ever smoked.

Practical Access

Australians who wish to be screened for AAA can:

Discuss the matter with their GP, who can refer for an abdominal ultrasound
Undergo private ultrasound at a radiology practice (a Medicare rebate may apply when requested for a clinical indication, though not as population screening)
Access some public vascular surgery outpatient services that offer opportunistic screening