Thoracic AAA1

Question 1

What is Laplace’s law

Answer 1

tension=pressure x radius

Question 2

MCC of thoracic AA

Answer 2

medial degeneration

Question 3

Why is Laplaces law important

Answer 3

it explains turbulent flow

Question 4

Define dissection

Answer 4

tear of inner aortic wall which weakens the outer wall

Question 5

When should elective surgery be done on thoracic AAAs

Answer 5

6.5cm or expansion of 1cm per year or if symptomatic

Question 6

Crawford classification conveys what

Answer 6

the extent of repair

Question 7

Define class I Crawford system of TAA

Answer 7

involving descending aorta, extending into the abdomen and involving the renal, coeliac and superior mesenteric artery origins

Question 8

Define class II of the Crawford system of TAA

Answer 8

involving most of the descending thoracic and abdominal aorta

Question 9

Define class III of the Crawford system of TAA

Answer 9

involves less than half the descending aorta and part of the abdominal aorta from which the visceral vessels arise

Question 10

Define class IV of the crawford system of TAA

Answer 10

confined to the abdominal aorta but involving the renal and visceral arteries

Question 11

MC of postoperative mortality

Answer 11

cardiac complications

Question 12

Why are lumbar drains placed for TAA repair

Answer 12

CSF drainage

Question 13

What do lumbar drains hopefully prevent

Answer 13

paraplegia

Question 14

TAAA repair: spinal cord and visceral protection during surgery is done by…

Answer 14

heparinization, permissive hypothermia, reattachment of segmental or lumbar arteries (T8-L1), perfusion of renal arteries at 4degrees celsius, sequential aortic clamping, CSF drain, left heart bypass

Question 15

What exposure is needed for a descending TAA repair

Answer 15

posterolateral thoracotomy in 5th or 6th intercostal space

Question 16

Where is the aortic clamp placed for a DTAA

Answer 16

distal to the left subclavian artery

Question 17

What incision is needed for a thoracoabdominal AAA repair

Answer 17

posterolateral between the scapula and the spinal process- 6th intercostal space

Question 18

What type of annual imaging should a post-op thoracic AAA undergo

Answer 18

CT chest and abdomen

Question 19

When is a TEVAR used in thoracic aneurysms

Answer 19

when treating degenerative descending thoracic abdominal aneurysm, elderly patients with severe comorbidities

Question 20

How long should the proximal fixation be for TEVARS

Answer 20

20mm

Question 21

What structure should the stent be cephalad to

Answer 21

celiac axis

Question 22

To obtain an appropriate landing zone what vessel is often occluded

Answer 22

subclavian artery

Question 23

what are the consequences of covered the subclavian artery

Answer 23

arm ischemia, stroke, paraplegia

Question 24

How can complications of covering the subclavian artery be prevented

Answer 24

left carotid - left subclavian bypass

Question 25

Complications of TEVAR

Answer 25

paraplegia, renal failure due to contrast for imaging to place TEVAR, endoleaks

Question 26

When are hybrid repairs performed

Answer 26

aortic arch and descending aorta involvement (�elephant trunk�)

Question 27

Is aneurysmal growth faster for saccular or fusiform aneurysms

Answer 27

saccular

Question 28

Sx's of thoracic aneurysms

Answer 28

chest pain , paralysis or hoarseness, back pain, hemetemesis, duodenal obstruction, jaundice

Question 29

What causes hoarseness

Answer 29

stretching of the recurrent laryngeal nerve

Question 30

Where do descending TAAs rupture

Answer 30

into the pleural cavity

Question 31

Dx aneurysms

Answer 31

CXR, US, Echo, CT, MRA, aortography or cardiac catheter

Question 32

When is surgery performed on asymptomatic patients for 1. ascending aorta 2. descending aorta 3. connective tissue ds 4. with atrial valve regurgitation

Answer 32

1. 5.5cm 2. 6.5cm or more than 1cm per yr 3. 5.0cm 4. 5.5cm

Question 33

In what condition must an open repair be performed

Answer 33

patients with connective tissues disorders; increased risk of dilation, stent migration and endoleak

Question 34

What organ systems are involved in the pre-op eval

Answer 34

cardiac, pulmonary and renal

Question 35

What FEV and PCO2 are needed for cardiac surgery

Answer 35

FEV greater than 1L, PCO2 less than 45