Vascular System Flashcards
(84 cards)
1
Q
What is the vascular system formed by ?
A
- arteries (elastic & muscular)
- arterioles (microscopic)
- capillaries (microscopic)
- venules (microscopic)
- veins
2
Q
what other vessels are also considered part of vascular system?
A
lymphatic
3
Q
microcirculation or systemic capillary bed is formed by ?
A
arterioles, capillaries, & venules
4
Q
Where does actual exchange between blood and tissue take place?
A
capillaries
5
Q
What can vascular lesions cause?
A
Edema, hemorrhage, thrombosis, ischemia, & infarction in affected tissues & organs
6
Q
5 degenerative diseases of arteries?
A
- Arteriosclerosis
- Atherosclerosis
- Arterial hypertrophy
- Aneurysms
- Arterial medial calcification
7
Q
Arteriosclerosis vs atherosclerosis?
A
They are distinct degenerative diseases of arteries that are manifested by hardening of arterial wall, loss of elasticity, & in many cases, reduced vascular lumen. In Atherosclerosis, lesions predispose to arterial rupture
8
Q
What degenerative disease of arteries other than Atherosclerosis also predisposes to arterial rupture?
A
Aneurysms
9
Q
what does artiosclerosis mean etymologically?
A
hardening of an artery
10
Q
What is arteriosclerosis?
A
degenerative change w/ loss of arterial elasticity, hardening, & luminal narrowing
11
Q
Where is arteriosclerosis mainly found?
A
elastic arteries (abd aorta); arterial branching sites are commonly affected
12
Q
gross appearance of arteriosclerosis?
A
intima has raised corrugated wht plaques (multiple coalescing areas of intimal thickening) while normal vessel has smooth surface
13
Q
what do arteriosclerosis plaques consist of ?
A
fibrous tissue & smooth muscle proliferation, sometimes mineralization
14
Q
What is atherosclerosis?
A
major cause of mortality in humans in which excessive circulating cholesterol is deposited in arterial walls
15
Q
how common is atherosclerosis in domestic animals?
A
comparatively rare compared to humans
16
Q
What does atherosclerosis lead to in humans?
A
acute myocardial infarction (heart attack); (prevalent in humans, relatively rare in domestic animals)
17
Q
major risk factors of atherosclerosis in humans?
A
- familial hypercholesterolemia
- high blood press
- poor diet habit (ex: junk food)
- sedentary life-style
- cigarette smoke
18
Q
What are atheromas?
A
cholesterol plaques in intima & media of arteries
19
Q
Where are atheromas particularly common?
A
coronary arteries (heart attacks) & in cerebral arteries (stroke)
20
Q
Where is atherosclerosis most commonly reported in domestic spp?
A
hypothyroid dogs w/ hypercholesterolemia or diabetes mellitus; Sw, psittacine birds, & pigeons fed high lipid diet
21
Q
steps in formation of atheromas?
A
- early cholesterol deposits in intima
- accumulation of cholesterol & lipid-laden macrophages in arterial wall
- large lipid plaques (atheromas) occlude arterial lumen & cause ischemia
22
Q
Gross appearance of atherosclerosis?
A
prominent thick arteries
23
Q
histo appearance of atherosclerosis?
A
atheromatous plaques contain foamy, lipid-laden macrophages, cholesterol clefts, fibroblasts, & smooth muscle proliferation
24
Q
Describe atherosclerosis in lovebird? (gross)
A
hx of progressive weight loss; on post mortem, mjr arteries were hard & rigid
25
Describe atherosclerosis in lovebird? (histo)
lipid laden macrophages in arterial wall; lumen of medium sized artery is markedly occluded
26
what is arterial hypertrophy?
another arterial change that occurs in muscular arteries; characterized by hypertrophy & hyperplasia of smooth muscle which results in loss of elasticity, narrowing of arterial lumen, & increased resistance
27
what is common cause of arterial hypertrophy?
hypertension
28
Describe arterial hypertrophy with brisket disease:
high altitude -> pulmonary hypertension -> medial hypertrophy of pulmonary arteries -> increase flow resistance -> dilation/hypertrophy of R ventricle -> R heart failure -> ascites & sub Q edema
29
histo appearance of pulmonary artery with brisket disease?
moderate hypertrophy of smooth muscle
30
history of arterial hypertrophy & pulmonary hypertension in Fe?
- muscular hypertrophy is frequently seen in lungs of Fe
- in past this change was associated w/ Aelurostrongylus abstrusus (feline lungworm), but this idea has been abandoned since identical lesions have been found in Specific Pathogen
31
Dirofilaria immitis (dog heartworm) in cats can cause?
both smooth muscle hypertrophy & intimal proliferation/inflammation (endoarteritis)
32
hypertension & medial hypertrophy in cats can also be caused by which disease?
renal disease
33
histo appearance of arterial hypertrophy in cats?
severe hypertrophy of smooth muscle, intimal proliferation, & narrowing of vascular lumen
34
What is an aneurysm?
localized weakening & dilation of blood vessels, particularly elastic arteries & to lesser extent veins
35
Two main anatomic types of aneurysms?
1. saccular (or fusiform) aneurysm: spherical or ovoid dilation of blood vessel resembling balloon filled w/ blood
2. dissecting aneurysm (arterial dissection): tear of intima allows blood to enter into potential space btwn intima & media, progressively dissecting wall of vessel
36
What are aneurysms prone to & what can this cause?
prone to rupture & can cause hemothorax, hemoabdomen, hemopericardium, brain hemorrhage, etc.
37
5 common causes of aneurysms in domestic animals are?
1. Strongylus vulgaris (nematode, blood worm) in Eq (aorta, cranial mesenteric artery)
2. spirocerca lupi (nematode, esophageal worm) in Ca (aorta)
3. copper deficiency in mares (uterine) & Sw
4. trauma
5. atherosclerosis & hypertension particularly in humans
38
spirocerca lupi (nematode, esophageal worm) in Ca
Not common in Canada unless brought from Central America or Mexico; migrate from wall of aorta to wall of esophagus; only affects wild canids & dogs; lesion is parasitic aortitis (distended & corrugated artery); can produce granulomas/ nodules in distal esophagus; can progress into fibrosarcomas
39
4 common causes of arterial calcification?
1. hypervitaminosis D or ingestion of toxic plants containing Vit D analogs that cause hypercalcemia & metastatic calcification
2. chronic granulomatous diseases ex: Johne's disease (paratuberculosis) & tuberculosis often results in arterial mineralization
3. age-related arteriosclerosis
4. aortic lesions associated w/ migrating larvae of Spirocerca lupi (nematode, esophageal worm) in Ca
40
gross appearance of arterial medial calcification?
corrugated surface & plaques of calcification
41
Gross appearance of aorta & intestine in cow w/ Johne's disease ?
- aortic calcification: confluent, raised, rectangular plaques on intimal surface
- intestine shows prominent thickening & folding of mucosa
42
what is fibrinoid necrosis?
unique but non-specific term used to describe vascular change primarily in sm arteries & arterioles characterized by microscopic deposition of acidophilic proteinaceous material (fibrin) in vascular walls
43
6 conditions associated w/ fibrinoid necrosis:
1. viral infections ex: classical swine fever, porcine circovirus
2. toxic conditions ex: uremia & mercury poisoning
3. bacterial toxins ex: enterotoxemia & edema disease of swine (E. coli)
4. nutritional deficiencies ex: mulberry heart disease
5. purpura hemorrhagica in Eq. following infections w/ Streptococcus equi
6. immune mediated vasculitis ex: lupus
44
histo appearance of fibrinoid necrosis & vasculitis in cerebral arterioles?
fibrinoid material & karyorrhectic debris in vascular walls
45
What is vasculitis?
generic term used in pathology that describes inflammation of sm arteries & veins; vasculitis is only detected by histopathology but its effect is grossly visible in affected tissues (hemorrhages, edema, or sm infarcts)
46
common causes of vasculitis include:
- systemic infections (virus, bact, fungi)
- hypersensitivities where Ag-Ab complexes attached to walls of blood vessels
- adverse drug reactions
47
Name two viral diseases causing vasculitis
malignant catarrhal fever & bovine viral diarrhea
48
Name two bact diseases causing vasculitis
Salmonella spp & histophilus somni
49
Name two fungal diseases causing vasculitis
mucor spp & aspergillus spp
50
Name two parasite diseases causing vasculitis
angiostrongylus vasorum (nematode, French heartworm) & spirocerca lupi
51
Name two toxin diseases causing vasculitis
ergotism (fungus: Claviceps purpurea) & festuca spp/ mycotoxin Fusarium
52
Name two immune mediated diseases causing vasculitis
systemic lupus erythematosus & rheumatoid arthritis
53
Gross appearance of vasculitis?
wht linear lesions
54
histo appearance of vasculitis?
fibrinoid necrosis (pink deposits) in renal arteries
55
Sequels to vasculitis?
palpebral & mesocolon edema in Sw, infectious thrombotic meningoencephalitis (ITME in cattle); mycotic (fungal) vasculitis w/ infarction & hemorrhages in omasum
56
Parasitic arteritis in Eq?
Can be seen on gross exam affecting lrg vessel; parasite is Strongylus vulgaris (nematode, blood worm); can cause colic in Eq
57
Dirofilaria immitis (dog heartworm)
adult form of this nematode parasitize R ventricle & pulmonary arteries where it can cause endoarteritis (roughened intimal surface)
58
Phlebitis?
term used to describe inflammation in veins
59
thrombophlebitis?
veins undergoing inflammation typically become thrombosed
60
4 most common forms of thrombophlebitis in vet practice are?
1. vena cava thrombosis: in Bo which is typically secondary to hepatic abscess eroding into wall of vena cava
2. omphalophlebitis: umbilical veins, particularly in farm animals, become infected & inflamed after birth
3. latrogenic phlebitis: in all spp caused by improper venipuncture
4. some parasites ex: schistosoma sp (blood fluke trematode) cause parasitic phlebitis
61
Vena cava thrombophlebitis?
hepatic abscess eroding into vena cava & causing thrombosis; pieces of infected thrombus often detach & are released into circulation causing embolic pneumonia
62
Embolic pneumonia?
sometimes these animals swallow lrg amts of blood & lrg amts of blood can be seen in feces; can cause sudden death due to ruptured pulmonary aneurysm
63
gross appearance of omphalophlebitis?
swollen umbilical vessels filled w/ purulent exudate; exudate is visible in cut umbilical vein
64
lymphangiectasia?
dilation of lymphatics secondary to accumulation of chyle, usually due to some sort of obstruction; can cause leakage into lumen of intestines & lead to hypoproteinemia
65
gross appearance of lymphangiectasia?
lymphatics in mesentery are markedly dilated w/ chyle (wht vessels)
66
histo appearance of lymphangiectasia?
lacteal dilation; subserosal dilation of lymphatic vessels w/ cluster of foamy macrophages
67
what is rupture of lymphatics & what are 2 presentations of this?
thoracic duct or cisterna chyli leak fluid;
1. chylous ascites in abd cavity
2. chylothorax (milky fluid)
68
5 types of lymphangitis?
1. Johne's disease (Mycobacterium avium subsp. paratuberculosis) Bo
2. glanders (burkholderia mallei) Eq
3. ulcerative lymphangitis (Corynebacterium pseudotuberculosis) Eq, Bo
4. Epizootic lymphangitis (Histoplasma farciminosum) Eq
5. Sporotrichosis (Sporothrix schenckii)
69
some primary cardiovascular tumours?
1. hemangioma & hemangiosarcoma
2. rhabdomyoma & rhabdomyosarcoma
3. myxoma & myxosarcoma
4. heart base tumour
- aortic body chemodectoma
- ectopic thyroid carcinoma
70
example of secondary (metastatic) cardiovascular tumours?
lymphoma
71
in dogs, where do hemangiosarcomas arise from?
various organs, primarily spleen & heart
72
cardiac hemangiosarcoma is important canine ...
malignancy
73
most common site for hemangiosarcoma?
R Atrium
74
hemangiosarcomas can cause?
cardiomegaly, hemopericardium, & cardiac tamponade
75
gross appearance of hemangiosarcoma?
neoplastic cells form channels filled w/ blood (typically dark red colour), enlarged cardiac silhouette, metastatic tumoral nodules in lung, dark red mass in R atrium
76
where do hemangiosarcomas readily metastasize to?
lungs & other organs ex: brain, kidneys, liver, etc.
77
What is a chemodectoma?
arises from chemoreceptors normally present in aorta; typically non-fxnal, but tumour can cause heart failure b/c of compression of R atrium, venae cavae, or great arteries
78
Differential for chemodectoma?
ectopic thyroid carcinoma
79
myxoma/myxosarcoma?
contain mixed matter, can embolize to lungs (benign so not metastasis
80
gross appearance of myxoma/myxosarcoma?
can look like bunch of grapes, can obliterate valves or lumen
81
gross appearance of lymphoma?
wht-yellow tumoral nodules on heart
82
histo appearance of lymphoma?
malignant cells infiltrating myocardium
83
Lymphoma (w/ multicentric form) in cattle older than 3 years may have resulted from?
bovine leukemia virus b/c takes time to develop after infection w/ virus
84
gross appearance of lymphoma in cow heart?
yellow nodular masses effacing atrium
