Aortic dissection

Question 1

Define aortic dissection

Answer 1

A disruption of the intima of the aortic wall, resulting in the layers separating and a false lumen forming

Question 2

What are the steps in pathophysiology for aortic dissection?

Answer 2

1. Initiating Event
2. Formation of False Lumen
3. Propagation
4. Complications
5. Clinical Manifestations

Question 3

Describe the initiating step in aortic dissection

Answer 3

It begins with a tear in the intimal layer, associated with mechanical wall stress (hypertension)

Question 4

Describe formation of the false lumen in aortic dissection

Answer 4

The tear allows blood to enter the aortic wall, creating a false lumen

Question 5

Describe propagation of aortic dissection

Answer 5

The dissection may extend along the aorta, affecting blood flow

Question 6

Describe complications in pathophysiology of aortic dissection

Answer 6

The false lumen can lead to compromised blood flow, organ ischemia, and the risk of rupture

Question 7

Describe clinical manifestations in pathophysiology of aortic dissection

Answer 7

Symptoms include severe chest or back pain, reflecting the impact on blood flow and organ function

Question 8

Which patients are at a greater risk of aortic dissection?

Answer 8

Ehlers-Danlos Syndrome and Marfan Syndrome patients have weakened connective tissues, leading to vulnerability of vessel walls and therefore they are at a greater risk of AD

Question 9

What is the most common site of AD?

Answer 9

First few cm of aorta/sinotubular junction

Question 10

What are the signs/symptoms of aortic dissection?

Answer 10

• Sudden, severe chest or back pain, often described as “tearing” or “ripping”
  
  • which may radiate to the
    neck, jaw, abdomen, or arms
• Pulse deficit
• Shortness of breath
• Weakness
• Sweating
• Loss of consciousness (syncope)
• Hypertension
• Tachycardia

Question 11

What are the risk factors for aortic dissection?

Answer 11

Hypertension (most important)
Smoking
Raised cholesterol
Pre-existing aortic diseases
Connective tissue disorders
Family history of aortic diseases
IV drug use
Trauma to the chest

Question 12

What are investigations for aortic dissection?

Answer 12

Unstable Patients
- Transthoracic/Transoesophageal echo
Diagnosis
- ECG
- Chest X-ray
- Contrast-enhanced CT angiogram

Question 13

What are complications of aortic dissection?

Answer 13

Cardiac Tamponade
Aortic insufficiency
Pre-renal AKI
Ischaemic stroke

Question 14

How is an aortic dissection classified?

Answer 14

• Stanford Classification
• DeBakey Classification
• An Aortic Dissection will fit into both classifications

Question 15

What is the Stanford classification for aortic dissection?

Answer 15

Type A = Proximal to the left subclavian artery (2/3 of cases)
Type B = Distal to the left subclavian artery (1/3 of cases)

Question 16

What is the DeBakey Classification
for aortic dissection?

Answer 16

Type I = Originates in ascending aorta and extends to at least the aortic arch
Type II = Originates from and is confined to the ascending aorta
Type III = Originates the in descending aorta and extends distally

Question 17

What is the treatment/management for aortic dissection?

Answer 17

Type A
- Blood transfusion
- IV labetalol (aim for 100-120 systolic)
- Urgent open surgical repair

Type B
- Conservative management
- IV labetalol (aim for 100-120 systolic)
- Thoracic Endovascular Aortic Repair (TEVAR) may be performed