Aortic Dissection Flashcards
What is AD?
- tear in the intimal layer of the aortic wall, causing blood to flow between and splitting apart the tunica intima and media

What are the two types of AD?
- Acute
- <=14 days
- Chronic
- >14days
What can AD progress to?
- progress distally, proximally, or in both directions from the point of origin.
- Anterograde dissections propagate towards the iliac arteries
- retrograde dissections propagate towards the aortic valve
What are the two classifications used for AD?
- Standford Classification
- DeBakey Classification
Describe the Stanford classification
- Group A
- DeBakey Types 1&2
- Involves ascending aorta, can propagate to arch or descending aorta
- Group B
- DeBakey Type 3
- X involve ascending aorta

Describe the DeBakey Classification
- Type I: Involves the ascending aorta, dissection extends into arch and beyond
- Type II: Limited to the ascending aorta (proximal to brachiocephalic artery)
- Type IIIa: Involves the descending thoracic aorta (distal to left subclavian artery, proximal to coeliac artery)
- Type IIIb: Involves descending thoracic aorta and abdominal aorta

What are the RF for AD?
- Hypertension
- Atherosclerotic disease
- Male gender
- Connective tissue disorders* (typically Marfan’s syndrome or Ehler’s-Danlos syndrome)
- Biscuspid aortic valve
What are the clinical features of AD?
Symptoms
- Chest pain (classically tearing and maximal at onset, though frequently this is not seen)
- Back pain
- Abdominal pain
- Dyspnea
- Syncope / collapse
Signs
- Intra-arm blood pressure differential
- Neurological deficit
- Horners syndrome
- Absent peripheral pulses
What are the cx of AD?
- cardiac tamponade
- aortic regurgitation
What is the classical triad seen in cardiac tamponade?
Beck’s Triad
- Raised JVP
- Muffled heart sounds
- Hypotension
How would acute aortic regurgitation present?
- Diastolic murmur
- Wide pulse pressure
- Signs of heart failure
What are the differentials for AD?
- MI
- PE
- Pericarditis
- MSK back pain
What Ix would you order for AD?
Bedside
- Bilateral BP - may be different for both
- ECG - may show MI
Bloods
- FBC (leucocytosis may be present)
- U&E
- LFT
- Clotting screen
- D-DIMER (may be elevated)
- Troponin (may be elevated in dissection or indicate the involvement of coronary vessels)
- ABG / VBG
- Group & Save / Cross-match
What imaging would you order for AD?
- CXR - widened midiastinum, pericardial effusion
- CT angiogram - definitive imaing
- Aortography - gold standard. but may be inconvinient to perform
- MRI
- Echocardiogram - assess cardiac tamponade & aortic regurgitation
How would you mx Standford Type A?
- transfer to cardiothoracic centre
- emergency surgery
- removal of the ascending aorta and replacement with synthetic graft
How would you mx Standford Type B?
Uncomplicated Stanford B dissections
- blood pressure mx
- analgesia
Standford B dissections with Cx
- urgent surgery
What cx would warrant surgical intervention in Standford Type B?
- rupture
- renal, visceral or limb ischaemia
- refectory pain
- uncontrollable hypertension
What are the Cx of AD?
- Aortic rupture
- Aortic regurgitation
- Myocardial ischaemia
- Secondary to coronary artery dissection
- Cardiac tamponade
- Stroke or paraplegia