Thoracic Aortic Aneurysm

Question 1

Definition of aneurysm

Answer 1

Persistent, abnormal dilation of an artery 1.5 times its normal diameter

Question 2

What can TAA involve?

Answer 2

Ascending aorta or aortic root (60%)

Aortic arch (10%)

Descending aorta (40%)

Thoracoabdominal aorta segments (10%)

Question 3

Main causes of TAA

Answer 3

Marfan’s/EDS

Bicuspid aortic valve

Question 4

Other causes

Answer 4

Trauma

Aortic dissection

Aortic arteritis like Takayasu

Tertiary syphilis

Question 5

How quick do TAAs grow?

Answer 5

Mean rate of 1-2 mm/year

Even higher in Marfan’s, descending aneurysms and a dissected aneurysm

Question 6

Risk factors

Answer 6

FH

HTN

Atherosclerosis

Smoking

High BMI

Male

Advancing age

Question 7

Clinical features of TAA

Answer 7

Typically asymptomatic and found incidentally

Ascending aorta -> Anterior chest pain

Aortic arch -> Neck pain

Descending aorta -> Pain between scapulae

Question 8

Other symptoms of thoracic aneurysm

Answer 8

Back pain secondary to spinal compression by desceing or thoracoabdominal aneurysm

Hoarse voice from arch aneurysms

Distended neck veins from SVCO

Symptoms of heart failure

Dyspnoea or cough

Question 9

Dx

Answer 9

Acute coronary syndomres

PE

Pneumothorax

Aortic dissection

Question 10

Initial lab tests

Answer 10

FBC U&Es, clotting

ECG and a CXR are usually performed as well

Question 11

Imaging

Answer 11

Can be seen on plain CXR (but not sensitive enough to make definitive diagnosis)

CT chest with IV contrast is the imaging of choice

Transoesophageal echocardiography (TOE) can also be used to further detect any concurrent aortic insufficiency or dissection and is part of routine assessment in Marfan’s.

Question 12

CXR findings

Answer 12

Widened mediastinal silhouette

Enlarged aortic knob

Possible tracheal deviation

Question 13

Management

Answer 13

Medical management with statin and anti-platelet therapy to reduce risk of MI

BP control + smoking cessation

Question 14

Indications for surgical intervention

Answer 14

Ascending aorta affect with diameter >5.5cm

Aortic arch once over 5.5 cm

Descending aorta once >6cm

Question 15

Surgical approach of ascending aorta.

Answer 15

Affected region is excised and replaed with a dacron graft

If aortic root is involved a Bentall procedure is performed using a graft that also contains a prosthetic valve

Question 16

Surgical approach of aortic arch.

Answer 16

Affected aorta is replaced with a multi-limbed graft.

This allows for branching with the arteries.

Question 17

Surgical approach of descending aorta

Answer 17

Open or endovascular repair

Question 18

Complications

Answer 18

Development of a second aneurysm

Perioperative mortality 2-17% (arch aneurysm highest mortality 25%)

Mortality is lower if you do endovascular repair