Diseases of the thoracic aorta

Question 1

Describe the histology of thw aorta

Answer 1

Tunica Intima

• layer of endothelial cells
• subendothelial layer - collagen and elastic fibres
• seperated fro T.media and internal elastic membrane

Tunica media

• smooth muscle cells
• secretes elastin in the form of sheets/lamelle

Tunica adventitia

• thin connective tissue layer
• collagen fibres and elastic fibres

Question 2

Function of collagen in T.adventia

Answer 2

-the collagen in T.adventia prevents the elastic arteries from stretching beyond their physiological limits during systole

Question 3

State the risk factors of atherosclerosis

Answer 3

Hypertension
Hypercholesterolaemia
smoking
diabetes
FMX
M>F ( untill menopause)

Question 4

What can severe atherosclerosis lead to?

Answer 4

• Stroke
• MI
• aneurysm

Question 5

What is an aneurysm

Answer 5

-localised enlargement of an artery caused by the weakening of the vessel

Question 6

Types of anerysm

Answer 6

• True(saccular[unequal]/fusiform[equal])
• False
• Dissecting

Question 7

What is a true aneurysm

Answer 7

-aneurysm that involes all 3 layers

Question 8

Causes of true aneurysms

Answer 8

• Hypertension
• atherosclerosis
• smoking
• collagen abnormalities ( marfan’s, cystic medial necrosis)
• ttrauma
• infection ( mycotic/syphillis)

Question 9

What is a false aneurysm

Answer 9

-rupture of a wall of aorta with the haematoma contained by T.adventia or surrounding tissue

Question 10

Causes of false aneurysms

Answer 10

• inflammation ( endocarditis with septal emboli)
• trauma
• iatrogenic ( catheters)

Question 11

What is an aortic dissection?

Answer 11

tear in T.intima of aorta + blood forces the walls apart

-acute(E)/chronic

Question 12

Types of thoracic aortic dissections

Answer 12

Debankey
Type I
Type II
Type III

Stanford
Type A - dissection involving ascending aorta
Type B - all dissections except asending aorta

Question 13

Risk factors of aortic dissection

Answer 13

• hyper tension
• atherosclerosis
• trauma
• marfan’s syndrome

Question 14

Problems of aortic dissection

Answer 14

• occlude branches ( mesenteric, carotid, renal, spinal)

- Can rupture back into the lumen/externally into meiastinum/pericardium( tamponade)

Question 15

Dilation of ascending aorta in an aortic dissection

Answer 15

-dilation of ascending aorta may cause acute aortic regurgitation

Question 16

What can a false lumen lead to?

Answer 16

-antegrade/retrograde direction

Question 17

Symptoms of aortic dissection

Answer 17

• chest pain that radiates to back

- collapse ( tompanade, acute AR external rupture)

Question 18

Examination of aortic dissecion

Answer 18

-low/absent peripheral pulses ( BP mismatch between sides )
-hypotension/hyper
-diastolic murmur ( AR)
-pul.oedema
-CXR shows widened mediastinum
-

Question 19

Investigation of aortic dissection

Answer 19

• CXR shows widened mediastinum
• CT scan
• ECHO

Question 20

Treatment of aortic dissection

Answer 20

Type A
-surgery

Type B

• meyiculous blood pressure control
• sodium nitroprusside + beta blocker

Question 21

Microbes responsible of infection and inflammation of AI

Answer 21

Infection;syphillis

inflammation; takayasu’s arteritis

Question 22

What is Takayasu’s arteritis

Answer 22

a family of rare disorders characterized by inflammation of the blood vessels, which can restrict blood flow and damage vital organs and tissues.

Question 23

What does granulomatous vasculitis affect?

Answer 23

• aorta and main branches

- causes stenosis, thrombosis, aneurysms, renal artery stenosis and neurological sx

Question 24

What is granulomatous vasculitis?

Answer 24

• a type of takayasu’s arteritis

Question 25

Risk factors of takayasu's arteritis

Answer 25

F>M

Question 26

Treatment of granulomatous vasculitis

Answer 26

-steroids, surgery

Question 27

Where is syphillis from?

Answer 27

Primary(chancre)/Secondary - STD - trepenoma pallidum

Question 28

Treatment of syphillis

Answer 28

Primary/secondary Abx Tertiary

Question 29

Without treatment of teritiary syhphillis what cant this lead to?

Answer 29

- late neurosyphillis - gummatous syphillis - cardiac syphillis ( sypillitic aortitis which is an aneurysm and aortic regurgitation)

Question 30

State conditions that can lead tocongenital aneurysms?

Answer 30

- bicuspid aortic valve - marfan's syndrome - coarctation

Question 31

What can bicuspid aortic valve lead to?

Answer 31

- associated with coarctation - cbnormal aorta ( reduced tensile steength) - prone to aneurysm/disssection/stenosis

Question 32

Monitoring bicuspid aortic valve

Answer 32

ECHO | MRI

Question 33

3 shunts in coarctation

Answer 33

- ductus arteriosus - foramen ovale - cutus venosus

Question 34

Types of coarctation

Answer 34

- aortic narrowing to where ductus arteriosus inserts ( ligamentum arteriosum) 3 types: - preductal( can be life threatening if severe narrowing) - ductul - postductal ( most common in adults, hypertension in upper extemeties, weak pulses in lower limbs) ; associated with rib notching ( collateral circulation)

Question 35

Clinical signs of coarcation

Answer 35

-cold legs -poor leg pulses -if before subclav then radial- radial + right radial-femoral delay -If after subclav then no radial-radial delay -right and left radio-femoral delay

Question 36

Symptoms of coarctation

Answer 36

Infancy(severe) -HF, failure to thrive Adults -Hypertension

Question 37

Imaging of Coarctation

Answer 37

CXR | CMRI