Diseases of the Aorta Flashcards
Aortic anatomy:
3 layers of the aorta
- inner intima
- middle media
- outer adventitia
-structures degenerate w/ age d/t collagen degradation (also degenerate w/ smoking or long-standing HTN)
-thoracic aorta (ascending aorta, aortic arch, descending thoracic aorta)
-abdominal aorta (begins once the descending aorta passes through the diaphragm, separated into suprarenal and infrarenal)
Aortic aneurysms
-segmental (only 1 segment not entire aorta), full-thickness (all 3 layers distended) dilation of the aorta (greater than 50% of the normal diameter)
Abdominal aortic aneurysm (AAA)
-any dilation >3cm
-MC arterial aneurysm (4x higher risk in males 50yo+)
RF of AAA
HTN
smoking
elevated cholesterol
age
male
atherosclerosis
FH (genetic predisposition)
Sx of AAA
likely none if unruptured
ruptured AAA: pain, pulsatile mass, hypotension
Screening for AAA
US
-screen 65-75yo w/ FH (1st degree relative) of AAA repair or death by a ruptured AAA
-screen MEN 65-75yo who have EVER SMOKED
Dx studies for AAA
-US to screen and if symptomatic + hemodynamically unstable (emergent)
-CT for hemodynamically stable pts; also used for surgical planning
AAA: management
-ruptured aneurysms require emergency surgery (very high mortality, ~80%)
-symptomatic, unruptured aneurysms require urgent surgery
-asymptomatic unruptured aneurysms: watchful waiting, if <5cm (r/o rupture > r/o surgery once 5.5cm+)
thoracic aortic aneurysms of the ascending aorta are associated with what conditions?
Marfan syndrome
Ehlers-Danlos syndrome
(both collagen disorders)
thoracic aortic aneurysms of the descending aorta are associated with what conditions?
HTN
Atherosclerosis
Clinical presentation of pt w/ thoracic aortic aneurysm
-~1/2 are symptomatic
-may apply pressure to adjacent structures (trachea, esophagus, recurrent laryngeal n. (SOB, loss of vocal pitch, hoarseness, choking/coughing while swallowing))
-chest pain
Thoracic aortic aneurysm: PE
may feel aortic impulse in R upper sternal border
Thoracic aortic aneurysm: Dx test
-CXR: widening of the mediastinal silhouette
-MRI & spiral CT are most commonly used for dx
Thoracic aortic aneurysm: Tx
-control BP (B-blockers)
-if <5cm unlikely to rupture (monitor); >7cm are high risk (consider TEVAR - thoracic endovascular aortic repair)
-aneurysms that are invading local structures should be resected
aortic dissection
tear in intima w/ development of a hematoma btwn the intima and adventitia
Stanford classification system of aortic dissection (& what each is associated with)
A: involves ASCENDING aorta; high mortality if untreated; associated with connective tissue disorders
B: DESCENDING aorta only; associated with long-standing HTN; age
DeBakey classification system of aortic dissection
Type I: involves entire aorta
Type II: involves only ascending aorta
Type III: spares the ascending aorta and arch
Aortic dissection: RF
-HTN
-old age
-male
-preexisting aortic aneurysm
-atherosclerosis
Less common:
-connective tissue d/o
-vascular inflammation
-deceleration trauma (injury d/t sudden halt)
aortic dissection: clinical presentation
ABRUPT PAIN IN BACK/CHEST “tearing pain”
Type A: may have syncope or hypotension; stroke (lack of BF to brain & UE)
Type B: pain in back w/ radiation down legs
*both may present w/ pulse deficits
**high mortality!
aortic dissection: Dx tests
-CXR: widened mediastinum
-CT: method of choice for dx
aortic aneurysm vs dissection on CT scan
Aortic aneurysm: wide aorta w/ a WIDE lumen
Aortic dissection: wide aorta w/ a NARROW lumen
Aortic dissection: Tx
Surgical repair
-Type A: urgent surgical repair
-Type B: surgery w/ life-threatening complications (ischemia of kidneys, bowel, extremities; progression of aneurysm, impending rupture, extension of dissection)
Medical therapy:
-aggressively control BP (B-blockers)
Takayasu arteritis & epidemiology
inflammatory dz of aorta and major branches
-80-90% of cases involve WOMEN btwn 10-40yo
-highest prevalence in ASIA
-Probably autoimmune
clinical presentation of Takayasu arteritis
Early sx: fever, loss of appetite, wt loss, night sweats, arthralgias (constitutional sx = all over body)
-Claudication
-cyanosis
-lightheadedness (lack of BF to brain via carotids)
-tenderness over carotids
-diminished radial pulses & HTN in 50% pts, may be different btwn arms (d/t lack of BF to one or both arms w/ compensation (HTN) in opposite arm)
Takayasu arteritis: Dx tests
-ESR, CRP (nonspecific inflammatory markers)
-Normocytic normochromic anemia (body stores iron for later use so it’s unavailable –> anemia)
-MRA or CTA are best imaging modalities
Takayasu arteritis: Tx
Systemic glucocorticoids (steroids)
Giant cell arteritis (temporal arteritis) & epidemiology
-inflammation of temporal artery and adjacent vessels
-Old white pt (almost never occurs <50yo; Scandinavian descent)
-closely associated w/ polymyalgia rheumatica
clinical presentation of giant cell arteritis (temporal arteritis)
HA
fever
jaw claudication
***fear is PERMANENT VISION LOSS (1/5)
Giant cell arteritis (temporal arteritis): Dx tests
-ESR, CRP
-Arterial bx is essential for dx
Giant cell arteritis (temporal arteritis): Tx
-start steroids IMMEDIATELY, even before bx, to prevent potential permanent vision loss
coarctation of the aorta & epidemiology
-localized narrowing of the aorta
-most commonly just distal to the origin of the L subclavian a.
-affects 4/10,000 (typically congenital)
-cause of secondary HTN
classic PE finding of coarctation of the aorta
decreased pulse/BP in legs compared to the arms
Coarctation of the aorta: Sx
-CHF in neonates
-HTN is typical presentation in adults
Coarctation of aorta: Dx tests
echo
Coarctation of aorta: Tx
surgical stent placement
What dz is the “3 sign” associated w/?
coarctation of aorta
-seen on x-ray (notch of “3” in the aorta is location of coarctation/narrowing)
Rib notching: what is it and what dz may it be associated w/?
-rib abnormalities on x-ray (notching)
-w/ coarctation of the aorta there is so much blood going into the subclavian and intercostal arteries that it is causing damage to the ribs
