Diseases Of The Aorta / Cardiac Patho Test 2/2 Flashcards
The descending aorta becomes fixed to the thorax by the intercostal arteries, LSCA, and _____?
Ligamentum arteriosum
The ascending aorta and arch are:
Mobile
At what point does the descending aorta become fixed to the thorax?
Aortic Isthmus
Recite the regions of the aorta starting from the valve?
Ascending Aorta
Transverse Arch
Descending Aorta
Abdominal Aorta
Weakening of an artery involving all three layers of the vessel is called what?
Localized Dilation
Aortic aneurysm that represents 3/4 of atherosclerotic aneurysms?
Where or what level do they occur?
Abdominal
Between the renal arteries and the bifurcation.
Thoracic dilation can occur anywhere along the thoracic aorta, what is the most common site ?
Arch and descending aorta
Perianeurysmal fibrosis (10%) May cause what?
Urethral obstruction
90% of abdominal aortic aneurysms are ?
Infrarenal
Abdominal aortic aneurysm statistics?
Focal widening >3 cm
> 60 yrs
M:F = 5:1
What is one major Abdominal aortic aneurysm complication?
25% rupture into the left retroperitoneum, GI tract, IVC.
What are 3 other Abdominal aortic aneurysm complications?
Peripheral embolization
Infection
Spontaneous occlusion of the Aorta
What is the normal size of a thoracic aortic aneurysm and wt what point does it tend to rupture?
Normal size = 4-5 cm
Rupture at = 10 cm
Statistics of thoracic aortic aneurysms?
Mean age = 65 yrs
M:F = 3:1
thoracic aortic aneurysm are associated with ?
HTN
CAD
AAA
Symptoms of a thoracic aortic aneurysm ?
Subsepternal, back, and shoulder pain experienced by 25%. SVC syndrome Dysphagia Stridor Dyspnea Hoarseness
What is the gold standard for evaluation of aneurysm?
Angiography
Etiology of descending aortic aneurysms?
80% atherosclerotic
Percentage of descending aortic aneurysms do to post traumatic circumstances ?
15%
CHDs that can lead to descending aortic aneurysms?
2% post coarctation, & ductus diverticulum
Syphilis can lead to what type of aneurysms?
Ascending aortic aneurysms
And
Arch aneurysms
3 conditions that can lead to arteritis?
Takayasu
Giant cell
Relapsing polychondritis
3 conditions that can lead to cystic medial necrosis ?
Marfan
Ehlers-Dantos
Annuloaortic ectasia
Aneurysms arise in areas of dense ?
Atherosclerosis
Atherosclerosis erodes into the aortic wall and destroys ?
Medial elements
During atherosclerotic aortic aneurysms the aorta widens and then what happens?
Tension increases, which accelerates the process.
Blunt trauma to the chest AKA
De-acceleration injury
Rupture of the Aorta occurs in ____ of all fatal auto accidents?
1/6
What is the most common site of aortic rupture during fatal car accidents ?
Ligamentum Arteriosum
What does syphilitic heart disease primarily effect?
Media of the Thoracic Aorta.
AI is common
Etiology of Mycotic Aneurysm of the Aorta?
IV drug use
Bacterial endocarditis 12%
Immunocompromise
S/P AV surgery, CABG
Organisms that cause Mycotic Aneurysm of the Aorta?
S. Aureus (53%)
Salmonella (33-50%)
Streptococcus
Sites of Mycotic Aneurysm of the Aorta?
Ascending aorta >
Visceral artery >
intracranial Artery >
upper/lower extremity arteries
Inflation of the aorta ?
Takayasu Arteritis AKA
Giant cell Arteritis
Aortic arch syndrome
Pulseless disease
thickening of wall of aortic arch + thoracic aorta.
chronic obliterative arteritis of + carotid arteries subclavian.
diminished pulses in upper extremities
may ==>
rib notching
Cystic Medial Necrosis of the Aorta Seen in
elastic arteries
Cystic Medial Necrosis of the Aorta Characterized histologically by
deposits of amorphous basophilic accumulations “Microcysts”
within the media
“Microcysts” can coalesce and interrupt the elastic fibers causing
weakening.
Marfan’s Syndrome
Connective-tissue disorder: autosomal dominant,
15% sporadic
Marfan’s Syndrome
- aortic aneurysm (mostly ascending)
- dilatation of aortic sinuses
- aortic dissection
- coarctation
- tall stature, long limbs
- arachnodactyly
- lax joints
- scoliosis (60%) / kyphosis / pectus
- dural ectasia
- lens subluxation
Aortic dissection Caused by
sudden tear in intima allowing for a column of blood to enter the Ao wall
What is a prerequisite for Aortic dissection?
Degeneration of media
Aortic dissection can be described as ?
Cystic medial necrosis-deterioration of collagen and elastic tissues
Aortic dissection is common in what medical syndrome?
Marfan’s syndrome
DeBakey Type I Aortic dissection
ascending Ao and beyond
DeBakey Type II Aortic dissection
confined to ascending Ao
DeBakey Type IIIa Aortic dissection
descending, confined to thorax
DeBakey Type IIIb Aortic dissection
descending, extends beyond diaphram
Shumway/Stanford Type A
origin in ascending
Shumway/Stanford Type B
origin in descending
what are the three main surgical options for descending aortic lesions?
Clamp & run
Shunt
Left heart bypass
Explain the shunt surgical option for descending aortic lesions?
a Gott Shunt is placed from above the aneursym and connected beyond the distal clamp. Simple but one can not easily control flow through shunt
Type III Descending Aortic Lesion requires Clamping the aorta to correct the lesion, which then results in hypoxia and ischemia to the lower body. What are three complication s that we can face?
Paraplegia
Renal failure
Ischemia-reperfusion injury
What is Left Heart Bypass?
Taking blood from the LA and returning it through the femoral artery. Bypasses the LV.
Is an oxygenator required for Left Heart Bypass ?
No, blood in LA is fully oxygenated
When would we need to use left heart bypass?
Type III Aortic Aneurysms
To assist/support a failing ventricle LVAD, RVAD, BiVAD
Perfusion Parameters for left heart bypass?
Pump Flows can be 1/2 what you would flow with full CPB.
Be careful to balance the upper body and lower body perfusion! Don’t sacrifice good cerebral perfusion!
Cardiac index for lowerbody perfusion?
1.0
Treatment for an Aortic disses ton Type A ?
Ascending dissection requires surgery
Treatment for an Aortic disses ton Type B ?
Descending dissection can be medically managed by controlling BP and preventing extension.
What are the 2 components of the surgical adhesive?
Bovine Serum Albumin
Glutaraldehyde
Bioglue curing time?
Starts 20-30seconds
Finished in 3 minutes
Aortic dissection outcomes with medical treatment ?
80% 1 year survival
50% 3-5 year survival
Operational mortality for ascending ?
5 -10%
Operational mortality for descending ?
10%
Operational mortality for arch ?
10 -25%
Operational 10yr survival for aortic dissection?
46%
Percentage risk for a
re-dissection?
10%
Remember: you are dealing with 2 circuits that share 1 source:
The upper body is perfused by the LV ejections.
The lower body is being perfused by the pump.
If you are measuring arterial pressures in the upper body then you have
a inverse relationship between pressure and pump flow