Transcript CVT 109 - University Health

CVT 109

Vascular Physiology
Introduction
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The purpose of this portion of CVT 109 is
to teach physiology relavant to noninvasive vascular technology.
Major areas of interrogation
Intracranial cerebrovascular
 Extracranial cerebrovascular
 Abdominal visceral vascular
 Peripheral arterial
 Peripheral venous
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Normal Endothelial
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This is about as
normal as an adult
aorta in America
gets. The faint
reddish staining is
from hemoglobin that
leaked from RBC's
following death. The
surface is quite
smooth, with only
occasional faint
small yellow lipid
streaks visible.
Development and
sequela of
atherosclerosis.
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A disease of the intima extending
to the media of the arterial wall.
Abnormal build up of lipid and
collegen cells.
Extends into and narrows the
lumen of the artery.
Chronic in nature.
Content changes with age.
Stages of development
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Lipid deposits in the intima
subintimal collagen deposits
intrude into lumen, narrowing
lumen
epithelial covering
fibrin accumulates
as more lipid accumulates the
atheroma becomes larger.
Macrophages die, lipid is released
and acts as an irritant.
Development cont.
/ Calcium formation
/ hemorrhage in the atheroma- from vaso vasorm or into
the lesion from the surface.
/ atheroma breakdown
/ endothelial rupture (plaque ulceration)
/ embolization - any of the constituants
/ occlusion - thrombosing
/ weakening of the arterial wall-aneurysm
Sequela
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Hemodynamic lesions
 area
and diameter stenosis
 occlusion
 flow reduction to distal vascular
bed
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embolization
 portions
of the plaque breaking off
and obstructing flow distally.
 Any material in the plaque can
move.
Areas of incidence of Atherosclerotic Lesions
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Cerebral
Coronary
Aorta
Renal
Extremities
Mesenteric
Cerebral
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Stroke/TIA/Rind
Thrombosis
Embolic
Hemorrhage
Coronary
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Angina
MI
Aorta
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Hemodynamic lesions
Dissection
Aneurysm
Renal
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Hemodynamic Lesions
 Hypertension:
decreased distal
renal artery pressure activates
renin-angiotensin system.
Decreased renal function
Atrophy of Kidney
Mesenteric
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Hemodynamic/Embolic lesions
 Bowel
arterial insufficiency
 Intestinal
angina
 Intestinal gangrene
Upper Extremities
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Hemodynamic lesions
 Highest
incidence in subclavian
region.
 Causes
“subclavian steal
syndrome”. Neurological
symptoms.
 Rarely causes arm ischemia
Upper extremity cont:
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Radial and ulnar atherosclerotic
lesions occur more frequently in
diabetic patients and renal
patients.
Upper ext cont
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Embolic ischemia of upper
extremities can result from
atherosclerosis in the following
locations. Emboli from
atherosclerotic lesions to upper ext
is much less common than to lower
extremities. Tends to affect digits.
Emoli to upper ext come from
aorta, heart, and prox subclavian.
Lower Extremity
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Hemodynamic Lesions cause
ischemia to lower legs and feet.
Claudication: Pain or tiredness of a
muscle group, brought on by
exercise and relieved by rest.
Ischemic rest pain: Pain in lower
leg and foot brought on by rest and
relieved by exercise.
Lower extremity cont.
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Emboli are a factor in lower
extremity ischemia. Most likely
sources include.
 Heart
 Aortic
aneurysm
 Iliac aneurysm
 Poplital aneurysm