Aortic Aneurysm

Question 1

What is an aneurysm.

Answer 1

An artery with a dilation of more than 50% of its original diameter.

Question 2

What are the two forms of aneurysms.

Answer 2

True.

False (pseudoaneurysm).

Question 3

What is a true aneurysm.

Answer 3

It is an abnormal permanent dilation of an artery or in the heart involving all the layers of vessel wall.

Question 4

What are the two types of true aneurysms.

Answer 4

Saccular (protrudes from one side of the vessel, eg Berry aneurysms).
Fisuform (generalised dilation of the vessel, eg most AAAs).

Question 5

What type of aneurysm are most AAAs. (2)

Answer 5

True aneurysms.

Fusiform.

Question 6

What is the most common cause of a true aneurysm.

Answer 6

Atherosclerosis.

Question 7

What are the causes of true aneurysms. (5)

Answer 7

Congenital weakness (eg berry aneurysm in circle of willis, Marfan’s syndrome).
Degenerative (AAA due to atherosclerosis).
Trauma (injury to a vessel wall).
Infection (bacterial arteritis).
Inflammatory (Kawasaki disease, Takayasu’s aortitis).

Question 8

What is a false aneurysm.

Answer 8

A haematoma containing liquid blood (in the adventitia- outer layer of the blood vessel) which communicates with blood in the arterial lumen.

Question 9

What is the cause of false aneurysms.

Answer 9

Due to trauma. (eg iatrogenic arterial puncture for angiography)

Question 10

What are the signs of false aneurysms. (2)

Answer 10

Pulsatile mass with history of trauma or arterial puncture.

Question 11

What is a common cause of false aneurysms.

Answer 11

Commonly diagnosed after groin post-angioplasty. (if a pulsatile mass is present)

Question 12

What is a popliteal aneurysm.

Answer 12

It is the commonest peripheral aneurysm.

Question 13

What percentage of patients with AAA go on to develop a popliteal aneurysm.

Answer 13

10%.

Question 14

Are popliteal aneurysms more commonly unilateral or bilateral.

Answer 14

Bilateral.

Question 15

What are the symptoms of popliteal aneurysms.

Answer 15

Often asymptomatic.

Question 16

What are the signs of a popliteal aneurysm. (2)

Answer 16

Pulsatile mass (possibly bilateral). 
Distal ischaemia following thrombosis or embolization.

Question 17

What are the common sites of aneurysms. (4)

Answer 17

Aorta (infrarenal most common). 
Iliac artery. 
Femoral artery. 
Popliteal artery. 
(in decreasing frequency)

Question 18

What are the complications of aneurysms. (5)

Answer 18

Rupture. 
Thrombosis. 
Embolism. 
Fistulae. 
Pressure on other structures.

Question 19

Who gets screened for aneurysms in the UK.

Answer 19

All men at age 65.

It decreases the mortality from a ruptured AAA.

Question 20

What is a rare infective cause or aortaitis that will then produce saccular aneurysms.

Answer 20

Syphilis (usually tertiary).

Question 21

Where do aneurysms usually develop in aortitis.

Answer 21

In the ascending aorta.

Question 22

What conditions are associated with aortitis. (5)

Answer 22

Takayasu's disease. 
Syphilis. 
Reiter's syndrome. 
Giant cell arteritis. 
Ankylosing Spondylitis.

Question 23

What clinical features are associated with thoracic aortic aneurysms. (5)

Answer 23

Chest pain.
Aortic regurgitation.
Compressive symptoms such as stridor (trachea, bronchus) and hoarseness (recurrent laryngeal nerve).
Superior vena cava syndrome.

Question 24

What is a complication of thoracic aorta aneurysms.

Answer 24

If they erode into adjacent structures (eg aorto-oesophageal fistula)

Question 25

What occurs if an aorto-oesophageal fistula is present.

Answer 25

Massive bleeding.

Question 26

Why does the haematoma of a false aneurysm occur.

Answer 26

Because of inadequate compression of the entry site and continued bleeding into the surrounding soft tissue. (this forms the wall of this aneurysm).