Chapter 11- Blood Vessels Flashcards
1
Q
What are the two mechanisms of vascular pathology?
A
- Stenosis/obstruction
2. Weakening of vessel walls
2
Q
What are the three layers of blood vessels?
A
- Intima
- Media
- Adventitia
3
Q
What separates the layers of the vessels?
A
Elastic lamina (internal and external)
4
Q
What is the vaso vasorum?
A
Arterioles that supply the outer vessel
5
Q
Where is the vasa vasorum found?
A
In the adventitia
6
Q
How do arteries and vessels differ?
A
Arteries are made up of well organized, concentric layers of smooth muscle (thicker wall)
Veins are thin walled and contain less organized muscle
7
Q
What are the three types of arteries?
A
- Large/elastic
- Medium/muscular
- Small and arterioles
8
Q
What layer do capillaries lack?
A
Media
9
Q
What vessels are a common place of inflammation?
A
Post capillary venules
10
Q
What are berry aneurysms?
A
Congenital weaknesses in cerebral vessels
11
Q
What are arteriovenous fistulas?
A
Abnormal artery-vein communication
12
Q
What is fibromuscular dysplasia?
A
Focal irregular thickening and attenuation of the arterial wall (alternating thick and thin areas due to hyperplasia and fibrosis)
13
Q
What is endothelial dysfunction?
A
Altered phenotype that affects vasoreactivity
Induced a thrombogenic surface
14
Q
What is the vascular wall response to injury?
A
- Endothelial cell’s are activates (thrombotic state)
- Vascular smooth muscle is recruited to the intima (thickening)
- Stenosis due to intimal thickening
15
Q
What is the stereotyped response to injury in vessel walls?
A
Stenosis
16
Q
What defines hypertension?
A
Diastolic pressure >89mmHg
Systolic pressure >139mmHg
17
Q
What is hypertension a risk for?
A
Coronary heart disease
Heart/renal failure
Aortic dissection
Atherosclerosis
18
Q
What is blood pressure a function of?
A
Cardiac output and peripheral vascular resistance
19
Q
What is cardiac output a function of?
A
Stroke volume and heart rate
20
Q
What is peripheral resistance regulated by?
A
Arterioles
21
Q
How is BP regulated when there is volume overload?
A
ANP secretion causes vasodilation and sodium excretion (water follows)
22
Q
How does high BP provide positive feedback resulting in maintenance of the hypertension?
A
Stenosis acts on kidney
Renin is released which activates angiotensin II
Vascular contraction, aldosterone secretion and sodium reabsorption increase BP
23
Q
What is hyaline arteriosclerosis?
A
Reduced vessel flexibility due to hyaline thickening
Luminal thickening, plasma and protein leakage
24
Q
What is hyperplastic arteriosclerosis?
A
Concentric lamina thickening (onion skin) with luminal narrowing
25
What are common causes of secondary hypertension?
Renovascular hypertension (renal artery stenosis)
Single gene disorders affecting aldosterone metabolism
Conn’s syndrome (primary hyperaldosteronism)
Liddel syndrome (affects proteins that influence sodium reabsorption)
26
What is arteriosclerosis?
Artery hardening- wall thickening and loss of elasticity
27
What is Monckeberg medical sclerosis?
Calcification of muscular artery walls
28
Does Monckeberg medial sclerosis affect the lumen?
No
29
How does atherosclerosis contribute to arteriosclerosis?
Causes hardening
30
What increases the risk of developing atherosclerosis?
```
Cholesterol
Smoking
Hypertension
LDL receptor mutations
Age
Obesity
Sex
Inflammation
Hyperhomocystinemia
Metabolic syndrome
Factors affecting hemostasis
```
31
What is the pathogenesis of atherosclerosis?
Endothelial injury causes the accumulation of lipoproteins which triggers inflammation
Monocytes migrate in and engulf the lipids releasing cytokines
GF drives smooth muscle proliferation and ECM deposition producing a plaque
32
What is an atheromatous plaque?
Raised lesion with a soft, grumous lipid core covered by a fibrous cap
33
How to plaques contribute to vessel pathology?
Obstruction
Rupture
Increase diffusion distance from lumen to media
34
What is the necrotic core of an atheromatous plaque made out of?
Lipid, debris from dead cells, foam cells, fibrin, thrombus, plasma proteins
35
What percentage of occlusion results in critical stenosis?
70%
36
What arteries are most commonly involved in atherosclerosis?
Heart, brain, kidneys and lower extremities
37
What are the two kinds of plaques?
1. Vulnerable- thin fibrous cap (rupture likely)
| 2. Stable- thick layer of smooth muscle cells
38
What are aneurysms?
Dilation did the heart or blood vessels that involve the entire wall thickness
39
What are the types of aneurysms?
1. True- saccular (one side) or fusiform (both sides)
| 2. False- rupture (held together by extravascular tissue)
40
What conditions can predispose someone to aneurysm?
Marfan syndrome
Inflammation (MMPs)
Cystic medial degeneration
Atherosclerosis (ischemia)
Systemic hypertension (ischemia)
Mycotic aneurism
41
Where does abdominal aortic aneurysm occur?
Below the renal arteries and above the bifurcation of the aorta
42
What are the characteristics of abdominal aortic aneurysms?
Atherosclerosis common
Male smokers over 50
Mural thrombi
Asymptomatic
Risk of rupture related to size
43
Why can abdominal aortic aneurysms affect the renal and superior/inferior mesenteric arteries?
Less collateral flow
44
What are the characteristics of thoracic aortic aneurysms?
Respiratory difficulties
Difficulty swallowing
Persistent cough
Hypertension/cardiac disease
Rupture
45
What causes syphilitic aneurysms?
Aortic valvular incompetence
46
What is an aortic dissection?
Tear in the intima, leading to separation of the layers, blood pools and travels within the wall
47
What increases risk of developing aortic dissection?
Hypertensive males 40-60
Younger people with connective tissue defects
Trauma
Complications from arterial cannulation
Pregnancy
48
When is aortic dissection uncommon?
Atherosclerosis or conditions with medial scarring
49
What are the direction of movement of spontaneous dissections?
Retrograde (toward heart)
Anterograde (into great arteries)
50
What can retrograde dissection cause?
Coronary compression or hemopericardium with tamponade
51
What is chronic dissection?
Vessel re-enters the lumen causing a double barrelled aorta
52
What are the types of spontaneous dissections?
A- 10cm from aortic valve
B- distal (usually to subclavian)
53
What type of spontaneous dissection is more common and dangerous?
A
54
What is vasculitis?
Vessel wall inflammation
55
What are the most common causes of vasculitis?
Inflammation and infection
56
How is vasculitis often diagnosed?
Blood tests for specific markers
57
What are the types of vasculitis?
Noninfectious
Giant cell (temporal) arteritis
Takayasu arteritis
Polyarteritis nodosa
Kawasaki disease
Microscopic polyangitis
Churg-Strauss syndrome
Bechet disease
Granulomatosis with polyangitis
Thromboangitis obliterans
Infectious vasculitis
58
What can noninfectious vasculitis be caused by?
Immune complex deposition
Anti-neutrophil cytoplasmic Abs
Anti-endothelial cell Abs
Autoreactive T-cells
59
What population is giant cell arteritis common in?
The elderly
60
What is a consequence of giant cell arteritis?
Fibrosis with medial scarring and luminal narrowing can cause blindness
61
What are the characteristics of Takayasu arteritis?
Granulomatous vasculitis of medium-large arteries
Thickening of aortic arch
Weakening of upper extremity pulse
62
What is Takayasu arteritis known as?
Pulseless disease
63
What is Takayasu disease in people over 50?
Giant cell arteritis
64
What is polyarteritis nodosa?
Segmental transmural necrotizing vasculitis of small-medium arteries in young adults
65
What is Kawasaki disease?
Medium-large vessel arteritis
Febrile illness of children
66
What is Kawasaki disease also known as?
Mucocutaneous lymph node syndrome
67
What is microscopic polyangitis?
Necrotizing vasculitis affecting capillaries, small arterioles and venules
68
What is Churg-Strauss syndrome?
Small vessel necrotizing vasculitis with eosinophilic infiltrates
69
What is Bechet disease?
Small-medium vessel neutrophilic vasculitis
70
Why is the Bechet disease triad?
Recurrent oral apthous ulcers
Genital ulcers
Uveitis
71
What is granulomatosis with polyangitis?
Necrotizing vasculitis of small-medium vessels
72
What is granulomatosis with polyangitis also known as?
Wegener granulomatosis
73
What is the granulomatosis with polyangitis triad?
Upper airway (mostly)
Necrotizing granulomas in upper and respiratory tracts
Glomerulonephritis
74
What is thromboangitis obliterans?
Segmental, thrombosing, acute and chronic inflammation of medium-small arteries
75
What is thromboangitis obliterans also known as?
Buerger disease
76
What are two disorders of blood vessel hyperreactivity?
1. Raynaud’s phenomenon- exaggerated vasoconstriction of arteries in extremities
2. Myocardial vessel vasospasm- excessive coronary artery constriction
77
What can cause myocardial vessel vasospasm?
Vasoactive mediators
Increased thyroid hormone
AutoAbs
78
What are varicose veins?
Superficial lower extremity veins that are dilated and tortuous
79
What are complication of varicose veins?
Stasis dermatitis
Ulcerations
Haemorrhoids
80
What causes esophageal varicies?
Portal vein hypertension increased flow to gastroesophageal veins
81
What is thrombophlebitis/phlebothrombosis?
Venous thrombosis and inflammation
82
What are superior/inferior vena cava syndromes?
Neoplasms compressing/invading the respective vessel
83
What are the clinical differences between superior and inferior vena cava syndromes?
Superior- dilation of head, neck and arm veins
Inferior- lower extremity edema, distension of superficial collateral veins of lower abdomen
84
What is lymphangitis?
Inflammation dues to infection spreading through lymphatics
85
What is lymphedema?
Lymphatic obstruction and dilation with increased interstitial fluid
86
What is fluid from lymphatics called?
Chylous ascites
Chylothorax
Chylopericardium
87
What are the different types of benign vascular tumours and their characteristics?
Vascular ectasias- local vessel dilation
Hemangiomas- pediatric
Lymphangioma
Glomus tumour- from modified smooth muscle cells of the glomus body
Bacillary angiomatosis- proliferation from opportunistic infection
88
What are the forms of vascular ectasias?
Nevus flammeus (port wine stain)- dermal vessel dilation
Spider telangiectasias
Hereditary hemorrhagic telangiectasia/Osler-Weber-Rendu disease
89
What are the four forms of hemangiomas?
1. Capillary- skin and mucous membranes
2. Cavernous- deep structures
3. Juvenile (“strawberry”)
4. Pyogenic granuloma- ulcerated polypoid variant of capillary, resemble proud flesh
90
What are the types of lympangiomas?
1. Capillary- blister-like blend
| 2. Cavernous/cystic hygromas- neck/axilla of children
91
What are the types of borderline tumours?
1. Kaposi sarcoma (HHV8)
| 2. Hemangioendotheliomas
92
What are the forms of Kaposi sarcoma?
1. Chronic/classic/European
2. Lymphadenopathic/African/endemic
3. Transplant associated
4. AIDS associated
93
What are the types of malignant tumours?
Angiosarcoma
Hemangiopericytoma
94
What are pericytes?
Contractile cell’s that wrap around endothelial cell’s in capillaries and venules
95
What interventions are possible when vascular pathologies are encountered?
Endovascular stenting
Vascular replacement
96
What areas do better with vascular replacement?
Large diameter vessels in high flow locations
97
What are complications of stents?
Thrombosis and intimal thickening
98
What are the two possible sites for graft harvesting?
1. Saphenous vein
| 2. Internal mammary artery (better outcome but less to use and atherosclerosis may be apparent)
