Flashcards in Path - Blood vessels Deck (68):
De novo formation of blood vessels during embryogenesis.
The process of new vessel formation in the mature organism (Neovascularization)
Remodeling of existing arteries in response to chronic changes in pressure or flow.
What is the predominant cellular element in the vascular media?
vascular smooth muscle cells
What is intimal thickening?
- stereotypic response to vascular injury
- Vascular injury → endothelial cell loss/dysfunction → muscle cells growth and matrix synthesis → intimal thickening (neointima)
What is the difference between neointimal SM cells & medial SM cells?
Neointimal smooth muscle cells do not contract, but are able to divide.
What are the steps of the intimal thickening process?
1. Migration of smooth muscle cells to the intima
2. Smooth muscle cells mitosis
3. Elaboration of extracellular matrix
At what blood pressure is it considered hypertensive? Malignant hypertensive?
Systolic > 139 mmHg, Diastolic > 89 mmHg
> 200/120 mmHg
What are the 2 classification of hypertension, and which one is more common?
1. idiopathic/primary/essential hypertension
2. secondary hypertension
idiopathic/primary/essential is more common.
What is the difference between the 2 classifications of hypertension?
1. idiopathic/primary/essential hypertension
- hereditary - familial/genetic factors
2. secondary hypertension
- caused by an identifiable underlying secondary cause
Hypertension causes what effects to the walls of large & medium arteries? What about to small blood vessels?
large & medium arteries:
- aortic dissection
- cerebrovascular hemorrhage
small blood vessels
- hyaline arteriolosclerosis
- hyperplastic arteriolosclerosis
What is an aortic dissection?
separation of aorta walls; tear in inner wall of aorta causes blood to flow betw layers of the wals of aorta, forcing layers apart
What is a cerebrovascular hemorrhage?
intracranial hemorrhage that occurs w/i brain tissue
What is hyaline arteriolosclerosis?
thickening/hardening of arteriole walls by deposition of hyaline material; narrowed lumen
What is hyperplastic arteriolosclerosis?
narrowed lumen; caused by malignant hypertension; prominent in kidney, can lead to schemia & acute renal failure
What are the 3 general patterns of arteriosclerosis? "Briefly" describe each of them.
1. Atherosclerosis – affects large elastic arteries (aorta and major branches) like heart attacks etc
2. Monckeberg’s medial calcific sclerosis – affects medium muscular arteries (arms and legs)
3. Arteriolosclerosis – affects arterioles
Between the ages 40 & 60, what has a fivefold increased incidence?
Why do males have a higher risk of atherosclerosis?
estrogen has an atheroprotective effect.
What is the "bad cholesterol" and what does it do?
Low-density lipoprotein (LDL) cholesterol - form of cholesterol delivered to peripheral tissue.
What is the "good cholesterol" and what does it do?
High-density lipoprotein (HDL) mobilizes cholesterol from tissue, transporting to the liver.
Higher levels of HDL have been correlated with reduced risk of atherosclerosis. T/F?
On the other hand, higher levels of LDL are correlated with increased risk of atherosclerosis.
Hypertension increases risk of ____ by approx 60% and causes left ventricular hypertrophy.
IHD (ischemic heart disease)
Diabetes increases the risk of stroke and a 100-fold increased risk for what?
atherosclerosis-induced gangrene of lower extremeties
What is C-reactive protein?
C-reactive protein (CRP) is an acute phase protein and its concentration in serum reflects the inflammatory condition of the patient
What is the morphology of an atheromatous plaque?
a raised lesion w/ a soft, yellow, grumous core of lipid (mainly cholesterol) covered by a white fibrous cap
What is the pathogenesis of atherosclerosis?
1. chronic endothelial injury
2. endothelial dysfunction
3. smooth muscle emigration from media to intima & macrophage activation
4. macrophages & SM cells engulf lipid
5. SM proliferation & other ECM deposition & extracellular lipid
What are some complications of atherosclerosis plaque changes?
1. Rupture, ulceration, or erosion → thrombosis → ischemia
2. Hemorrhage into a plaque
4. Aneurysm formation
What is the difference between vulnerable & stable atherosclerotic plaques?
- Vulnerable plaque, susceptible to rupture, ulceration or erosion of the luminal surface, with a thin fibrous cap, a large lipid core, and active inflammation (macrophages)
- Stable plaque, with densely collagenous and thickened fibrous cap with minimal inflammation
How can statins help reduce atherosclerosis formation/risk?
statins = a class of drugs which lowers circulating cholesterol levels (inhibit HMG-CoA reductase)
Difference between true and false aneurysm?
True aneurysms have an INTACT attenuated arterial wall or a thinned ventricular wall, while a false aneurysm involves a ventricular RUPTURE with an extravascular hematoma.
2 types of aneurysms?
sacular & fusiform
2 most important disorders predisposing to aortic aneurysms are?
atherosclerosis & hypertension
What is a berry aneurysm?
aka congenital aneurysm due to congenital weakness at bifurcation in Circle of Willis.
Aortic dissection usu occurs in what two groups?
1. Men aged 40-60 with hypertension
2. Younger patients with systemic or
localized abnormalities of connective tissue affecting the aorta (Marfan syndrome)
What is the morphology of an aortic dissection?
- Usually initiates w/ an intimal tear → extending the dissecting hematoma
- No inflammation
- Cystic medial degeneration as the most frequent pre-existing histologically detectable lesion
Difference between the 2 classifications of dissections? Which one has more serious complications?
A – Involves the ascending aorta and/or aortic arch, and possibly the descending aorta. It includes DeBakey types I and II.
B – Involves the descending aorta or the arch (distal to the left subclavian artery), without involvement of the ascending aorta. It includes DeBakey type III.
*The serious complications predominantly occur in type A dissections.
What is an example of a small vessel vasculitis?
granulomas, no asthma (Wegener granulomatosis)
What is an example of a medium vessel vasculitis?
immune complex mediated (polyarteritis nodosa)
What is an example of a large vessel vasculitis?
granulomatous disease (giant cell arteritis, Takayasu arteritis)
What is the most common form of vasculitis among old people in US & Europe? And describe it briefly.
Giant-cell (temporal) arteritis: chronic, granulomatous inflammation of large to small-sized arteries; predominantly in head.
- has nodular intimal thickening, reduced luminal diameter, medial granulomatous inflammation, elastic lamina fragmentation
- ex. of large vessel vasculitis
What is an oral manifestation of giant-cell (temporal) arteritis?
What is polyarteritis nodosa (PAD)?
- systemic vasculitis of small or medium-sized muscular arteries (usu renal & visceral aa's)
- starts w/ segmental transmural necrotizing inflamm
- may lead to thrombosis
What is Wegener Granulomatosis?
- Acute necrotizing granulomas of U/L respiratory tract or both
- Necrotizing or granulomatous vasculitis affecting small to medium-sized vessels
- Renal disease (necrotizing glomerulonephritis)
What is a useful marker of Wegener Granulomatosis's disease activity?
What is an oral manifestation of Wegener Granulomatosis?
strawberry gingivitis, palatal ulcers & perforation
What is Thromboangiitis Obliterans (Buerger Disease)?
- Segmental, thrombosing, acute and chronic inflammation of medium-sized and small arteries (tibial and radial arteries)
- Almost exclusively in heavy smokers, > 35 years old
What are early manifestations of Thromboangiitis Obliterans (Buerger Disease)? What are the chronic manifestations?
- Superficial nodular phelebitis
- Cold sensitivity of the Raynaud type in the hands
- Pain in the foot induced by exercise (instep claudication)
Chronic ulcerations followed in time by frank gangrene
What is the Raynaud Phenomenon?
- Fingers become white due to lack of blood flow, then blue as vessels dilate to keep blood in tissues, finally red as blood flow returns (RED, WHITE, & BLUE, BBY! 'MURICA)
- Results from an exaggerated vasoconstriction of digital arteries and arterioles
What are varicose veins?
- Abnormally dilated, tortuous veins
What is the cause of varicose veins?
prolonged, increased intraluminal pressure and loss of vessel wall
What is the diff betw Thrombophlebitis and Phlebothrombosis?
- Thrombophlebitis - inflammation of a vein w/ blood clot formation inside the vein
- Phlebothrombosis - thrombosis in vein w/o primary inflamm
Where are the majority of deep venous thrombosis (DVT)?
in deep leg veins (>90% of cases)
*Pulmonary embolism as a serious complication of DVT
What is Homan sign?
pain in the calf of the leg upon dorsiflexion of the foot with the leg extended that is diagnostic of thrombosis in the deep veins of the area
What is a vascular ectasia?
- Nevus Flammeous = most common form of vascular ectasia
- ectasia = local dilation
- telangiectasia = permanent dilation of pre-existing small vessels forming a red lesion
What is Sturge-Weber Syndrome (Encephalotrigeminal Angiomatosis)?
- a congenital disorder that is a special form of nevus flammeous
- ipsilateral venous angioma in cortical leptomeninges
- includes mental retardation, seizure, & hemiplegia ( paralysis of the arm, leg, and trunk on the same side of the body)
What is an arterio-venous (vascular) malformation?
- Uncommon errors on vascular morphogenesis
- Distinct from hemangioma (tumor of the endothelial cells that line BV’s)
- Not a neoplasm
- Present at birth but may not clinically evident
- Consist of abnormal channels lined by normal endothelium
What are the differences between vascular malformations VS infantile hemangioma?
Vascular malformation: present at birth, no rapid inc in size, no involution
Hemangioma: not always present at birth, rapid inc in size, involution
What is a pyogenic granuloma?
- Reactive Vascular Proliferations (Tumor-like Conditions)
- common, fast-growing lesion of the skin and mucous membranes
- Focal reactive growth of fibrovascular or granulation tissue with extensive endothelial cells proliferation
- gingiva = common site
Most common soft tissue tumors of infancy? And the common place for these tumors?
hemangioma (type of benign neoplasm); head & neck
What are the 2 types of lymphangiomas mentioned Describe them.
Lymphangiomas = benign neoplasms
1. Simple (capillary) lymphangiomas:
raised lesions, up to 1-2 cm, predominantly seen in head, neck, and axillary subcutaneous tissues
2. Cavernous lymphangiomas (cystic hygromas): found in the neck or axilla of children, up to 15 cm in size
What is an angiosarcoma?
- malignant endothelial neoplasm affecting older adults
- could get angiosarcoma in setting of lymphedema in pts w/ breast cancer after radical mastectomy
- associated w/ radiation
What compound is associated w/ lung cancer & angiosarcomas of the liver and brain?
What is an endothelial marker for angiosarcoma?
diffuse positivity of tumoral cells for CD31
What is Kaposi Sarcoma (KS)?
- a malignant vascular neoplasm that is caused by humans herpesvirus 8 (HHV8)
- highly associated w/ AIDS
- 4 forms of KS: classic, endemic african, transplant-associated, AIDS-associated (epidemic)
What is the classic type of Kaposi Sarcoma?
- A disorder of older men
- Associated with malignancy or altered immunity but not with HIV infection
- As multiple red-purple skin plaques or nodules
- Usu in distal lower extremities
What is the Endemic African type of Kaposi Sarcoma?
- In HIV-seronegative individuals
- Younger than age 40
- Lymph nodes /visceral involvement
- Aggressive course
What is the transplant-associated type of Kaposi Sarcoma?
- In solid organ transplant recipients in the setting of T-cell immunosuppression
- Aggressive course
- Lymph nodes, mucosa, and visceral involvement