Aortic Dissection

Question 1

Describe the clinical presentation for aortic dissection [5]

Answer 1

• Severe ‘tearing’ chest pain
• Chest AND abdominal pain
• Back pain
• Aortic regurgitation; diastolic murmur
• Hypertension
• Bicuspid valve disease
• Differences in blood pressure between the arms (more than a 20mmHg difference is significant)
• Radial pulse deficit (the radial pulse in one arm is decreased or absent and does not match the apex beat
• Horners syndrome

Question 2

Describe the pathophysiology of aortic dissection [2]

Answer 2

Tear in the tunica intima of the wall of the aorta, allowing blood to flow between the layers of the wall of the aorta.

A false lumen full of blood is formed within the wall of the aorta.

Question 3

What is the definitive imaging in suspected dissection? [1]

Answer 3

CT angiography of the chest, abdomen and pelvis is the investigation of choice

Question 4

DeBakey 1, Stanford 1
DeBakey 2, Stanford 1
DeBakey 3, Stanford 1
DeBakey 1, Stanford 2
DeBakey 2, Stanford 2
DeBakey 3, Stanford 2

Answer 4

DeBakey 1, Stanford 1

• DeBakey:
  involves ascending and descending aorta

Stanford 1:
- involves any part of the aorta proximal to the origin of the left subclavian artery

Question 5

Which is the area that most common for aortic dissection to occur? [1]

Answer 5

The right lateral area of the ascending aorta is the most common site of a tear of the intima layer, as this is under the most stress from blood exiting the heart}

Question 6

What are risk factors for aortic dissection? [3]

Answer 6

Hypertension:
- can be triggered by events that temporarily cause a dramatic increase in blood pressure, such as heavy weightlifting or the use of cocaine

Previous cardiac surgery

Genetic CT disorders
- Marfans syndrome
- Ehlers Danlos}

Question 7

What imaging modality is used to diagnose aortic dissection? [1]

Answer 7

CT Angiography

Question 8

What are the two different classification systems used for aortic dissection?

Answer 8

The Stanford system
The DeBakey system

Question 9

Describe how the Standford [2] and Debakey Systems [4] are used to classifiy aortic dissections

Answer 9

The Stanford system:
Type A – affects the ascending aorta, before the brachiocephalic artery
Type B – affects the descending aorta, after the left subclavian artery

Debakey system:
Type I – begins in the ascending aorta and involves at least the aortic arch, if not the whole aorta
Type II – isolated to the ascending aorta
Type IIIa – begins in the descending aorta and involves only the section above the diaphragm
Type IIIb – begins in the descending aorta and involves the aorta below the diaphragm

Question 10

Describe the managment of type A & B aortic dissections [2]

Answer 10

Type A:
- open aortic arch replacement with graft AND
- Beta blockers to control BP: labetalol, metoprolol (or verapamil)

Type B:
- Thoracic endovascular aortic repair (TEVAR): catheter inserted via the femoral artery inserting a stent graft into the affected section of the descending aorta
- Beta blockers to control BP: labetalol, metoprolol (or verapamil)

Question 11

Describe the pathophysiology of varicose veins [3]

Answer 11

The deep and superficial veins are connected by vessels called the perforating veins (or perforators): allow blood to flow from the superficial veins to the deep veins.

When the valves are incompetent in these perforators, blood flows from the deep veins back into the superficial veins and overloads them.

This leads to dilatation and engorgement of the superficial veins

Question 12

Aortic dissection can lead to:

• Mitral stenosis
• Mitral regurgitation
• Aortic stenosis
• Aortic regurgitation

Answer 12

Aortic regurgitation

Question 13

Aortic dissection can lead to which other cardiac complication? [1]

Answer 13

Cardiac tamponade

Question 14

Describe the treatment of acute Stanford Type A AD [1]

What is the blood pressure systolic target prior to this? [1]

Answer 14

Emergency surgery is indicated in suitable patients
(It carries a mortality of 50% in the first 48 hours in those not undergoing surgical intervention)

blood pressure should be controlled to a target systolic of 100-120 mmHg whilst awaiting intervention

Question 15

Describe the treatment for Stanford Type B AD

Answer 15

Type B:
- Thoracic endovascular aortic repair (TEVAR): catheter inserted via the femoral artery inserting a stent graft into the affected section of the descending aorta
- Beta blockers to control BP: labetalol, metoprolol (or verapamil)

Question 16

What pattern of MI is often seen in aortic dissection backwards tear? [1]
Why? [1]

Answer 16

MI: inferior pattern often seen due to right coronary involvement

Question 17

Answer 17

False lumen

Question 18

Answer 18

Widened mediastiun on CXR

Question 19

A patient has myocarditis and you suspect it is arising from an auto-immune disease.

You test their serum and find high levels of Ds-DNA.

What is the most likely diagnosis? [1]

Answer 19

systemic lupus erythematosus

Question 20

How do you determine if a patient is suffering from Type A or B aortic dissection based off symptoms? [2]

Answer 20

Type A dissections:
- weak pulses and aortic regurgitation
- more severe symptoms

Type B dissections
- typically do not involve acute aortic insufficiency, so findings related to heart failure may be less prominent

Question 21

Type A dissection is defined as a dissection proximal to the [] artery.

Answer 21

Type A dissection is defined as a dissection proximal to the brachiocephalic artery.

Question 22

How do you manage a type A aortic dissection? [1]

Answer 22

IV BB and surgery

The patient’s blood pressure must be controlled within 100 -120 mmHg (systolic) whilst awaiting surgical intervention, therefore IV labetalol must be given.

Question 23

How do you manage a type B aortic dissection? [1]

Answer 23

control BP(IV labetalol)