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1

What is surgical management of acute AI complicating dissection

Complicated by AI 75% of time, valve repairable in 85% of cases
Options
aortic valve repair (commisural resuspension) ascending aorta tube graft
valved-conduit
stentless free sytle
aortic valve-sparing

2

What is definition of aortic dissection

acute event in which blood leaves the normal aortic channel through an intimal tear and rapidly dissects between the inner and outer layers of an aortic media to produce a false lumen

classified as acute < 14 days and chronic > 14 days

3

What is incidence and natural history of aortic dissection

0.5 to 3 per 100 000; 85% are undetected
Coronary involvement in 11%
AI is found in 75% ; the majority are type A

Survival of type A is 43% at 1 month; 39% at 1 year; 33 % at 5 years and 27% at 10 years

50% of patients with type A dissection dies are in first 48 hours

4

Describe malperfusion syndrome

End organ ischemia due to compromise of the lumen of a branch artery by compression due to a false lumen, shearing off, or thrombosis.
a. renal 25-75%
b. limb 25-60%
c mesenteric 10 to 20 %
d. coronary
e. spinal/cerebral

5

What is operative and long term survival post dissection

Acute type A operative mortality is 20%
Survival is 55-75% at 5 years; 30 to 65% at 10 year

6

What are treatment options of 28 year old male with trauma and transected aorta

Open repair via thoractomy with tube graft or end to end is gold standard approach

Endovascular stent grafting is more common and likely becoming the gold standard

7

What are advantages to endovascular stenting of traumatic aortic injury

Avoidance of thoracotomy
No aortic cross clamping
shorter hospital stay
Shorter length of intubation
lower incidence of spinal cord ischemia
lower peioroperative morbiditiy and mortality
less need for systemic heparinazation
shorter length of ICU stay.

8

Describe 3 possible approaches to addressing the aortic valve at the time of dissection repair

1) Resuspension of the aortic valve commisures to the aortic wall before replacing the ascending aorta

2) valve sparing aortic root replacement with attachement of the valve inside the aortic graft and reimplantation of the coronary ostia

3) aortic root replacement with a mechanical composite graft or stentless porcine aortic root bioproshesis and reimplntation of the coronary ostia

9

Post type A aortic dissection repair

1) What do you do about the persistent flow in the false lumen

2) 2 months later patient develops left leg weakness and loss of sensation without signs any signs of ischemia?

3) An angiogram is done for the problem above and shows that false lumen is smaller? fewer lumbars and that the left renal artery is poorly visible?

1) No further operation on the aorta is needed: Accept the presence of persistent flow

2) spinal ischemia (loss of flow in the lateral part of the spine that is perfused via the false lumen. as the false lumen closes)

3) fenestration of the abdominal aorta (including origin of the left renal artery. could

10

58 year old man with medically treated type B dissection.

What is risk of developing an aortic aneurysm

What kind of follow up would you suggest

What are the indications for surgical repair in chronic dissection

1) 25% of the patient will develop an aortic dilation at 5 years. The risk increases to 45% if blood pressure is not controlled.

2) CT scan and MRI at discharge and 3 month, and then 6 months if aortic changes or Marfan every 12 months

11

How do you manage the distal anastomosis of an aortic dissection

Distal anastomosis has to be fashioned so that both true and false lumina are perfused if anastomosis is at the level of the distal dissection.

A wedge is performed in the septum which is then secure with sutures. If an anastomosis is beyond dissection or there is no flow to false lumen then a standard anastomosis is performed.

12

What surgical technique for coarctation is prone to aneursym repair.

What are 4 strategies that can be employed to reduce risk

1) lateral patch aortoplasty with dacron (or gortex) commonly used for coarctation repair predisposes to development of aneurysms oppose the patch

2) distal perfusion via femoral vein (or pulmonary artery)
distal perfusion via left atrium
distal perfusion via Gott shunt (ascending aorta to femoral artery)
use of cardiopulmonary bypass and profound hypothermic circulatory arrest

13

What is the main pathologic features and pathogeneis of IMH

Hemorrhage into the aortic media without an intimal tear.
Possible related to rupture of the vasa vasorum

14

What is natural history of IMH and what is recommended surgical treatment

About 1/3 with ascending aortic IMH progress to classic aortic dissection with intimal disruption, propagation of the dissection pane and risk of rupture or branch vessel compromise

Surgical approach is the same as for acute ascending aortic dissection with emergent dacron graft replacement of ascending aorta.

15

List 5 indications for early surgical intervention for type B dissection

Contained aortic rupture (hemothorax/hemomediastinum)
uncontrolled hypertension
uncontrolled pain
branch vessel compromise
aneurysmal expansion (> 5cm)
Malperfusion

16

Describe the 3 most common techniques for cerebral protection

Deep hypothermic circulatory arrest
Deep hypothermic circulatory arrest with retrograde cerebral perfusion
Deep hypothermic cirulatory arrest with selective antegrade cerebral perfusion

17

Concerning aortic dissection list 6 causative or associated conditions

Hypertension
Inheritable disorders: Marfan, Turner, Noonan, Ehlors-Danlos syndrome
Pregnancy
Bicuspid valve
coarctation
Medial degenerative disease
trauma
Inflammatory of infectious disorders
aneurysms
Polycyctic Kidney disease
iatrogenic

18

Describe 4 mechanisms by which patients with acute aortic dissection can die suddenly

Aortic rupture into mediastinum or pleural/abdominal cavity
aortic rupture into pericardium and tamponade
severe acute aortic valve insufficieny with cardiogenic shock
dissection of coroanry artery and myocardial infarction/shock
dissection of a carotid arterery with massive stroke

19

What are cardiovascular manifestations of Marfan

Aortic aneurysm
aortic dissection
Annuloaortic ectasia with AI
myxomatous MR
arrhythmias
pectus

*Review Ghent criteria*

20

What are indications for exploring femoral or axillary artery prior to redo sternotomy

Enlarged RV, RV to PA conduit
patent SVG to RCA
Insitu RITA to LAD
Multiple previous operations
Enlarged aneurysmal aorta
patent LITA to LAD when it crosses midline

21

What is rate of cooling for DHCA

slow cooling is preferred with perfusate/blood gradient of 4 to 6 degree.

22

What is Debakey

Debakey I ascending + arch + descending
Dbeakey II Ascending only
Debakey IIIa Decending only
Debakey IIIb Descending and abdominal

23

What is Cabrol operation

Cabrol graft for coronary reimplantation
if coronary ostia destroyed
single 6-8mm synthetic graft anastomised end to end to both coronary arteries
side to side anstomosis of synthetic graft to ascending aortic graft

24

What is cabrol shunt for hemorrhage

Patch fistula over ascending graft to right atrium

25

List risk factors of Type A or Type B dissection

Hypertension
Connective tissues disorder
Aortitis
Iatriogenic
Atherosclerosis
BAV
Trauma
Coarcation
Hypervolemia
Polycystic Kidney disease
Sheehans's syndrome
Cushing syndrome

26

What is incidence of aortic dissection

Occurs 3 x more frequent then abdominal
0.5 to 2.95/100 000

27

What is operative indication for chronic type B

Impending or actual rupture
Symptoms related to rupture
Malperfusion
Aneursym (>5.5 type A or > 6.5 type B)
Aortic expansion

28

After hemiarch repair of a type A dissection patient has antegrade flow in false lumen--what do you do

Common to have persistent flow in false lumen (>90% of patients after repair)
Aggressive treatment of HTN, follow up CT angio prior to discharge, at 3 and 6 month
Indications for operation in repaired type A or chronic type B dissection
a. rupture
b. intractable pain
c. malperfusion of end-organs
d. Aneurysm size
ascending aorta 5.5 of > 4.5 if connective tissues disorder
descending aorta 6.5cm of > 6 cm + Fhmx or CT disorder

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