Aortic dissection

Question 1

What is an aortic dissection?

Answer 1

tear in the intimal layer of the aortic wall causing blood to flow between and splitting apart the tunica intimal and media

Question 2

When is an aortic dissection classed as acute or chronic ?

Answer 2

when diagnosed less then 14 days, or chronic if more than 14 days

Question 3

Who are aortic dissections common in?

Answer 3

men and people with connective tissue disorders

Question 4

How can aortic dissections progress?

Answer 4

initial intimal tears can progress distally, proximally or in both directions from the point of origin,

Question 5

How do anterograde dissections propagate?

Answer 5

towards the iliac arteries

Question 6

How to retrograde dissections propagate?

Answer 6

towards the aortic valve at the root of the aorta, this can therefore cause prolapse of the aortic calve and bleeding into the pericardium and cardiac tamponade

Question 7

What is the DeBakey classification?

Answer 7

groups aortic dissections into 3 types

Question 8

What is a type 1 in the DeBakey classification and who are they most common in ?

Answer 8

originates the ascending aorta and propagates at least to the aortic arch (usually under 65 and high mortality rate)

Question 9

What is a type II DeBakey classification and who are they most common in?

Answer 9

confined to ascending aorta (usually see in elderly patients with atherosclerotic disease, hypertension)

Question 10

What is the type III DeBakey classification?

Answer 10

originates distal to the subclavian artery in the descending aorta , IIIa extends to the diaphragm and b extends beyond the diaphragm and into the abdominal aorta

Question 11

What is the stanford classification of aortic dissections?

Answer 11

divides into two groups A and B- A is Bebakeys I and II and involved the ascending aorta and can propagate to the aortic arch and descending aorta, the tear can originate anywhere along the path, Group B are type III DeBakeys, dissections do not involve the ascending aorta

Question 12

What are the risk factors for aortic dissections?

Answer 12

Hypertension, atherosclerotic disease male gender, connective tissue disorders like Marfans or Ehlers Danlos, Biscupsid aortic valve

Question 13

What are the symptoms of an aortic dissection?

Answer 13

tearing chest pain, radiating to the back, tachycardia, Hypotension, new aortic regurgitation murmur or signs of end organ hypo perfusion

Question 14

What are some signs of end organ hypo perfusion?

Answer 14

reduced urine output, paraplegia, lower limb ischameia, abdominal pain secondary to ischaemia, deteriorating conscious level

Question 15

What causes hypotension in an aortic dissection?

Answer 15

blood loss into the dissection or cariogenic from severe aortic regurgitation and pericardial tamponade

Question 16

What are the differential diagnosis for an aortic dissection?

Answer 16

MI, pulmonary embolism, pericarditis, musculoskeletal pain

Question 17

What are the investigations done for a suspected aortic dissection?

Answer 17

baseline blood tests such as FBC, U and E, LFTs, troponin and coagulation, crossmatch, arterial blood gas, ECG, CT angiogram as first line imaging, trans oesophageal ECHO can also be used

Question 18

What is the management for aortic dissection?

Answer 18

high flow oxygen, IV access with 2x large bore cannulae, fluids, type A surgically, Type B medically managed, antihypertensives and surveillance

Question 19

How are type A aortic dissections treated?

Answer 19

high mortality so usually removed the ascending aorta and replaces with synthetic graft, then nay additional branches od the aortic arch will require reimplanation into the graft

Question 20

How are type b aortic dissections treated?

Answer 20

Medically, by managing hypertension with IV beta blockers or CCB, this will minimise the stress of the dissection and limit further propagation, due to risk fo retrograde dissection in surgery, medical management is the best option, surgery is needed in complications,

Question 21

What are some complications of aortic dissections?

Answer 21

aortic rupture, aortic regurgitation, Myocardial ischaemia, cardiac tamponade, stroke, paraplegia, aneurysm formation