102014 peripheral vasc dis Flashcards
aneurysm
localized dilatation of blood vessel or heart
true aneurysm
involves all three layers of wall
false aneurysm
wall defect leading to extravascular hematoma
arterial dissection
blood enter the wall of the artery
in the setting of atherosclerosis/inflam, what can predispose to aneurysm formation?
polymorphisms of matrix metalloproteinase or tissue inhibitors of metalloproteinase genes
also increased MMP activity
pathogenesis of aneurysms
factors affecting collagen structure or fxn
loss of smooth muscle cells (due to atherosclerosis leading to thickening of intima and ischemia of inner media. or due to systemic HTN narrowing the vasa vasorum leading to ischemia of OUTER media)
common causes of anuerysms
atheroslcerosis –abodominal aorta
HTN – ascending aorta
uncommon causes of aneurysms
congenital defects infections (bacteria, fungi) -mycotic, syphilis trauma vasculitis genetic defects in collagen
mycotic anueryms
septic emboli, direct extension, direct infec by circulating organisms
what is the most common location of aortic aneurysm
abdominal aorta-below renal arteries and above bifrucation
aortic aneuryms are more common in whom
men, smokers
most common cause is atherosclerosis
morphology of aortic aneurysm
thinning and destruc of media
mural thrombus
saccular or fusiform
variants are: inflammatory (unknown cause), mycotic (secondary infec of an atherosclerotic wall)
aggressive managment is done for AAA greater than
5 cm, as the risk of rupture is proportional to size
thoracic aortic aneurysms causes
HTN (most common)
Marfan’s syndrome
syphilis
aortic dissection
blood btwn and along laminar planes of media
causes a blood filled channel that easily ruptures
pathogenesis and etiology of aortic dissec
HTN in over 90% of cases
connective tissue abnormality in association with Marfan’s syndrome or Ehlers Danlos
ascending aorta is most commonly involved
morphology of aortic dissec
intimal tear within 10 cm of aortic valve
dissection plane btwn middle and outer thirds of wall in media
in HTN pts: vasa vasorum has hyaline arteriolosclerosis and media has loss of sm musc cells.
cause of intimal tear in aortic dissec?
not usually known
clinical course of aortic dissec
dependent on level of aorta involved
sharp pain of anterior chest
uneven pulses and widened mediastinum
classic symptoms of aortic dissec
sudden onset of tearing or stabbing pain in anterior chest radiating to back
pathogenesis of vasculitis
immune mediated processes
infectious
unknown
pathogenesis of immune mediated vasculitis
immune complex mediated-SLE, hypersensitivity to drugs, viral infec like Hep B
ANCA associated
other mechanisms (antibodies to endothelial cells-Kawasaki’s)
ex of vasculitis of infectious origin
direct invasion:
classic ex is syphilis
Aspergillus and mucormycosis
indirect:
immune mechanisms triggering cross-reactivity
vasculitides of unknown origin
giant cell arteritis
Takayasu
PAN
what is the most common systemic vasculitis in adults
giant cell temporal arteritis
giant cell (temporal) arteritis
affects aorta and major branches, especially temporal artery, opthalmic, vertebral arteries
clinical presentation of giant cell arteritis
greater than 50 years old
often painful superficial temporal artery, diplopia, visual loss, headache
increased ESR
gross morphology of giant cell arteritis
nodular thickenings of artery with narrowed lumen
patchy (discontinuous) segments affected
histology of temporal arteritis
granulomatous inflam of inner half of media around internal elastic lamina
takayasu arteritis
pulseless disease (upper extremities) ocular disturbances
Japanese women younger than 40
granulomatou inflam of AORTIC ARCH AND ITS BRANCHES
pulmonary arteries are involved in 50%. coronary and renal arteries may be involved
histology of Takayasu arteritis
lymphocytes
giant cells
collagenous fibrosis
PAN
systemic SEGMENTAL, TRANSMURAL, NECROTIZING inflam of small or medium sized muscular arteries
renal and visceral arteries affected
SPARES LUNGS
young adults (30% with Hep B antigen)
classic presentation of PAN
rapidly accelerating HTN (renal artery involvement)
abdominal pain and bloody stools
peripheral neuritis
Kawasaki syndrome
large, medium and small arteries
OFTEN CORONARIES with aneurysm formation
mucocutaneous lymph node syndrome (mucous membrane inflam, enlarged lymph nodes)
80% under 4 years
histology of Kawasaki’s
necrosis and inflam
aneurysms
resembles PAN
MPA
arterioles, capillaries, venules
MPO-ANCA in 70%
Wegener’s granulomatosis
necrotizing vasculitis
GRANULOMAS of lung and or upper resp tract
glomerulonephritis
PR3-ANCAs present in more than 95%
males more than females
Churg Strauss syndrome
allergic granulomatosis with angiitis
small vessel vasculitis associated with asthma, allergic rhinitis, lung infiltrates, infiltration of vessels by EOSINOPHILS, EXTRAvascular necrotizing granulomas
MPO-ANCA is present in minority
clinical symptoms of Churg Strauss
palpable purpura
GI bleed
renal impairement
cardiomyopathy
Thromboangiitis obliterans/Buerger disease
inflam and thrombosis of medium to small sized muscular arteries and secondarily the veins and nerves
tibial and radial arteries
smokers
Israaeli, Indian, Japanese
painful ischemic disease
gangrene of limbs, requires amputation
Raynaud phenomenon
paroxysmal pallor or cyanosis of fingers, toes, nose, ears
primary-recurrent vasospasm of unknown case (exaggerated response to cold)
secondary-arterial insufficiency due to narrowing and can be due to SLE, systemic sclerosis, atheroslcerosis, Buerger disease
