Aortic Dissection Flashcards
What are the three layers of the aorta?
Intima
Media
Adventitia
What happens in aortic dissection?
Blood enters between the intima and media layers of the aorta
False lumen full of blood forms within the aorta wall
What is the most common site of aortic dissection?
Right lateral area of ascending aorta
As this under the most stress from blood exiting the heart
How are aortic dissections classified?
Stanford system
Type A - Affects ascending aorta before the brachiocephalic artery
Type B - Affects the descending aorta, after the left subclavian artery
DeBakey system
Type I - Begins in ascending aorta and involves at least the aortic arch
Type II - Isolated to ascending aorta
Type IIIa - Begins in descending aorta and involves only the section above diaphragm
Type IIIb - Begins in the descending aorta and involves the aorta below the diaphragm
What are the risk factors of aortic dissection?
Male
Smoking
Hypertension
Poor diet
Sedentary lifestyle
Raised cholesterol
What events can temporarily cause a dramatic increase in blood pressure leading to aortic dissection?
Heavy weightlifting
Cocaine use
What conditions affect the risk of aortic dissection?
Bicuspid aortic valve
Coarctation of the aorta
Aortic valve replacement
CABG
Ehlers-Danlos Syndrome
Marfan’s syndrome
How does aortic dissection present?
Sudden onset severe ripping or tearing chest pain
Anterior chest pain when ascending aorta affected
Back pain if descending aorta affected
Pain can migrate over time
Some patients may not have chest pain
What signs can indicate aortic dissection?
- Hypertension
- Differences in blood pressure between arms, more than 20mmHg
- Radial pulse deficit
- Diastolic murmur
- Focal neurological deficit
- Chest and abdominal pain
- Collapse
- Hypotension
How is aortic dissection diagnosed?
ECG and CXR used to exclude other causes
CT angiogram
Initial investigation to confirm the diagnosis
MRI angiogram
Provides greater detail, can help, but takes longer to get
How is aortic dissection managed?
Surgical emergency
- Analgesia e.g. morphine
- Blood pressure and heart rate need to be reduced to reduce stress on aortic walls- Beta-blockers
- Surgical intervention
What are the types of surgical management for aortic dissection?
Type A
Treated with open surgery (midline sternotomy)
Remove section of aorta and replace with synthetic graft
Aortic valve may need to be replaced during procedure too
Type B
Thoracic endovascular aortic repair
Catheter inserted via femoral artery, inserting a stent into affected section of descending aorta
What are the complications of aortic dissection?
MI
Stroke
Paraplegia
Cardiac tamponade
Aortic valve regurgitation
Death
