Aortic Aneurysm

Question 1

What is the definition of an aneurysm?

Answer 1

A permanent, focal dilation of an artery with at least a 50% increase in diameter compared to normal.

Question 2

What defines an abdominal aortic aneurysm (AAA)?

Answer 2

An infrarenal abdominal aorta with an anteroposterior diameter greater than 3 cm.

Question 3

Which population has the highest incidence of AAA?

Answer 3

Caucasian men over 65 years old.

Question 4

What percentage of men over 65 have an AAA?

Answer 4

About 5%.

Question 5

How does AAA prevalence differ between sexes?

Answer 5

It is four to five times more common in males than females.

Question 6

Why are women not routinely screened for AAA in the UK?

Answer 6

Because the prevalence is lower, making screening less cost-effective.

Question 7

How does aneurysm size affect rupture risk?

Answer 7

The risk of rupture increases exponentially with increasing aneurysm size.

Question 8

What is the approximate annual rupture risk for AAA smaller than 5.5 cm?

Answer 8

Less than 1% per year.

Question 9

What is the most common cause of AAA?

Answer 9

Atherosclerosis (degenerative disease).

Question 10

What are rare causes of AAA?

Answer 10

• Infection (mycotic aneurysm), connective tissue disorders (Marfan syndrome, Ehlers-Danlos)
• arteritis.

Question 11

Which condition appears to have a protective effect against AAA?

Answer 11

Diabetes.

Question 12

What is the UK screening programme for AAA?

Answer 12

National Abdominal Aortic Aneurysm Screening Programme (NAAASP).

Question 13

At what age are men invited for AAA screening in the UK?

Answer 13

65 years old.

Question 14

What imaging modality is used for AAA screening?

Answer 14

Abdominal ultrasound.

Question 15

What happens if the aortic diameter is less than 3 cm?

Answer 15

No further scans are required.

Question 16

How is a small AAA defined?

Answer 16

Aortic diameter 3–4.4 cm.

Question 17

How often are small AAAs monitored?

Answer 17

Yearly ultrasound scans.

Question 18

How is a medium AAA defined?

Answer 18

Aortic diameter 4.5–5.4 cm.

Question 19

How often are medium AAAs monitored?

Answer 19

Every 3 months.

Question 20

When is an AAA considered large?

Answer 20

Diameter ≥5.5 cm.

Question 21

What happens if an AAA reaches 5.5 cm?

Answer 21

The patient is referred to a vascular surgeon for management.

Question 22

Are most AAAs symptomatic?

Answer 22

No, they are usually asymptomatic until rupture.

Question 23

What symptoms may occur in large or expanding AAA?

Answer 23

Back pain or hip pain.

Question 24

What symptoms may occur if AAA compresses surrounding structures?

Answer 24

Vague gastrointestinal symptoms or deep vein thrombosis.

Question 25

What complication can occur if thrombus embolises from an aneurysm?

Answer 25

Acute lower limb ischaemia.

Question 26

What are the classic symptoms of ruptured AAA?

Answer 26

Abdominal pain radiating to the back and shock.

Question 27

Why should clinicians have a low threshold for suspecting ruptured AAA?

Answer 27

Because it can mimic other conditions such as renal colic, sciatica, or pancreatitis.

Question 28

What is the outcome of untreated ruptured AAA?

Answer 28

It is fatal without surgical repair.

Question 29

What is the management for AAA smaller than 5.5 cm?

Answer 29

Ultrasound surveillance and risk factor modification.

Question 30

What lifestyle changes are recommended for AAA patients?

Answer 30

- Smoking cessation - blood pressure control, statins - antiplatelet therapy.

Question 31

What imaging is performed when an AAA reaches 5.5 cm?

Answer 31

CT scan.

Question 32

What is the purpose of CT imaging before repair?

Answer 32

To assess suitability for open or endovascular repair.

Question 33

Why is repair usually recommended at 5.5 cm?

Answer 33

Because the risk of rupture outweighs the risk of surgery.

Question 34

Who reviews elective AAA cases before surgery?

Answer 34

A vascular multidisciplinary team (MDT).

Question 35

What is the first investigation in suspected ruptured AAA?

Answer 35

Urgent CT scan (if the patient is stable).

Question 36

What are the treatment options for ruptured AAA?

Answer 36

Open surgical repair or endovascular aneurysm repair (EVAR).

Question 37

When may palliation be considered in ruptured AAA?

Answer 37

When patient factors make survival unlikely.

Question 38

What is the in-hospital mortality rate for open AAA repair?

Answer 38

Approximately 2.9%.

Question 39

What is the in-hospital mortality rate for EVAR?

Answer 39

Approximately 0.4%.

Question 40

What was the 30-day mortality for open repair in the IMPROVE trial?

Answer 40

37.4%.

Question 41

What was the 30-day mortality for EVAR in the IMPROVE trial?

Answer 41

35.4%.

Question 42

Was there a significant mortality difference between EVAR and open repair in ruptured AAA?

Answer 42

No statistically significant difference.

Question 43

Who should be screened for AAA in the UK?

Answer 43

Men aged 65 years.

Question 44

What is the definitive treatment for large AAA (>5.5 cm)?

Answer 44

Surgical repair (open surgery or EVAR).

Question 45

What is the goal of AAA screening and monitoring?

Answer 45

To repair the aneurysm before rupture occurs.

Question 46

In which patients should ruptured AAA be strongly suspected?

Answer 46

Patients over 65 presenting with abdominal pain and shock.