8/24- Pathology of the Aorta Flashcards
Describe the intima (of the aorta)?
Single layer of endothelial cells, loose CT (GAG) and internal elastic lamina (diffusion of thin intima)
Describe the media (of the aorta)?
How does it receive nutrients?
- Smooth muscle
- Elastic lamellae: // to distribute pressure load
- Collagen: cross-linked: provide strength
Pressure shouldn’t deform!
Gets nutrients from diffusion from lumen through intima
Describe the adventitia (of the aorta)?
Encircles media contains loose CT, nerves, and arteries (vaso vasorum)
What is the number 1 cause of hypertension in kids?
Always secondary; here, in the aorta– due to coarctation
What is a key finding in aortic coarctation?
Rib notching on CXR
- Due to decreased blood flow from posterior intercostals (come straight from aorta; below coarctation) with increased blood flow from anterior intercostals (from subclavian)
- Results in wavy/tortuous arteries that can be see on CXR
What are the different types of aortic coarctation?
- Infantile or pre-ductal
- Adult or post-ductal
What is the treatment for aortic coarctation?
Ressection and end-anastamosis (treat early!)
What is the cause of morbidity/mortality with aortic coarctation?
- HTN
- CHF (L heart failure due to hypertrophy and then R)
- Rupture (increased P in head and neck)
- Endocarditis
Case)
- 24 yo male; 6’4” thin male…
Think Marfan’s!
What causes problems in Marfan’s syndrome?
Defective synthesis of fibrillin -> increased TGF-beta activity and weakening of the elastic tissue -> progressive dilation due to remodeling of the inelastic media
Why is aneurysm and dissection mostly in the ascending aorta in Marfan patients?
Related to LaPlace’s law: WS ~ Pr/2h
What are some congenital diseases that predispose to aneurysm formation:
- Marfan’s syndrome
- Loeys Dietz syndrome
- Ehlers-Danlos syndrome
What is the mechanism behind Loeys-Dietz syndrome?
Mutations in TGF-beta cause abnormal elastin and collagen I and III
What is the mechanism behind Ehlers-Danlos syndrome?
Defective type III collagen
What are some acquired aortic disease and age-related changes?
- Decrease in elastic fiber: dilatation and aneurysms
- Atherosclerosis:AA aneurysms
- ?
Aortic root dilatation causes what?
Aortic valve incompetence (insufficiency?)
T/F: unfolding of the aorta is a change associated with aging?
True
- Aorta straightens out
- Increased length of descending aorta
- (Must be distinguished from aortic aneurysm)
T/F: atherosclerosis is a change associated with aging?
True
- In the elderly, atherosclerosis is more often irreversible (in middle age there was more adaptive thickening; reversible)