Aortic dissection questions Flashcards

1
Q

What is surgical management of acute AI complicating dissection

A

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

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What is definition of aortic dissection

A

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

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What is incidence and natural history of aortic dissection

A

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

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Describe malperfusion syndrome

A
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
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What is operative and long term survival post dissection

A

Acute type A operative mortality is 20%

Survival is 55-75% at 5 years; 30 to 65% at 10 year

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

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

A

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

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What are advantages to endovascular stenting of traumatic aortic injury

A
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.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

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

A

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

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

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?

A

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

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

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

A

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

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

How do you manage the distal anastomosis of an aortic dissection

A

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.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What surgical technique for coarctation is prone to aneursym repair.

What are 4 strategies that can be employed to reduce risk

A

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

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What is the main pathologic features and pathogeneis of IMH

A

Hemorrhage into the aortic media without an intimal tear.

Possible related to rupture of the vasa vasorum

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

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

A

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.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

List 5 indications for early surgical intervention for type B dissection

A
Contained aortic rupture (hemothorax/hemomediastinum) 
uncontrolled hypertension 
uncontrolled pain
branch vessel compromise 
aneurysmal expansion (> 5cm) 
Malperfusion
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Describe the 3 most common techniques for cerebral protection

A

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

17
Q

Concerning aortic dissection list 6 causative or associated conditions

A
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
Q

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

A

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
Q

What are cardiovascular manifestations of Marfan

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

Review Ghent criteria

20
Q

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

A
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
Q

What is rate of cooling for DHCA

A

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

22
Q

What is Debakey

A

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

23
Q

What is Cabrol operation

A

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
Q

What is cabrol shunt for hemorrhage

A

Patch fistula over ascending graft to right atrium

25
Q

List risk factors of Type A or Type B dissection

A
Hypertension 
Connective tissues disorder
Aortitis
Iatriogenic
Atherosclerosis 
BAV 
Trauma 
Coarcation 
Hypervolemia
Polycystic Kidney disease 
Sheehans's syndrome 
Cushing syndrome
26
Q

What is incidence of aortic dissection

A

Occurs 3 x more frequent then abdominal

0.5 to 2.95/100 000

27
Q

What is operative indication for chronic type B

A
Impending or actual rupture 
Symptoms related to rupture 
Malperfusion 
Aneursym (>5.5 type A or > 6.5 type B) 
Aortic expansion
28
Q

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

A

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