Ch 11-Blood Vessels-Galbraith PDF's Flashcards
This vascular anomaly is an artery –> vein connection, is most commonly a developmental defect, but may arise secondary to inflammation and trauma
AV fistula
An AV fistula may lead to: ___
Rupture and hemorrhage or to high-output cardiac failure
This vascular anomaly is a focal thickening of intima and media of medium to large muscular arteries, resulting in stenosis
Fibomuscular dysplasia
Looks like beads on a string. Think Renal a.
List some stimuli that may induce an activated state of endothelium in response to injury:
Turbulent blood flow HTN Complement, bacterial products, lipid products, glycation end products Viruses Hypoxia, acidosis
The stereotypical response to vascular injury is ___
Intimal thickening
- Smooth muscle cells from the media migrate to the intima, where they proliferate and elaborate ECM
- The intima is thus thickened, potentially affecting blood flow in that vessel
___ is seen in response to any injury to a vessel, regardless of cause
Vascular intimal thickening
What are some risk factors for essential HTN?
High Na intake Obesity Stress Smoking Physical inactivity
What are some humoral factors that cause peripheral constriction?
Ang II Catecholamines Thromboxane Leukotrienes Endothelin
What are some humoral factors that cause peripheral dilation?
PG’s
Kinins
NO
What are neural factors that cause peripheral constriction?
What are neural factors that cause peripheral dilation?
Constrictors=alpha adrenergic
Dilators=beta adrenergic
Blood volume and vascular tone is modified and maintained by the ___
RAAS
This morphologic change seen in HTN is characterized by an increased smooth muscle matrix synthesis, plasma protein leakage across damaged endothelium, and a homogenous pink thickening of the vessel wall with associated luminal narrowing
Hyaline arteriolosclerosis
Usually seen in smaller arterioles
This morphologic change seen in HTN occurs in severe HTN, the smooth muscle cells form concentric lamellations with resultant luminal narrowing
Hyperplastic arteriolosclerosis
Concentric lamellations=”ONION SKINNING”
What are some constitutional risk factors associated with atherosclerosis?
FH
age
Gender
What are some modifiable risk factors (major) associated with atherosclerosis?
Hyperlipidemia (especially LDL)
HTN
Smoking
DM
List the steps involved in the response to injury model of the pathogenesis of atherosclerosis:
1) Chronic endothelial injury —> 2) Endothelial dysfunction —> 3) Macrophage activation, smooth muscle recruitment —> 4) Macrophages and smooth muscle cells engulf lipid (foam cells) —> 5) smooth muscle proliferation, collagen and other ECM deposition, EC lipid (this stage has a fibrofatty atheroma with fibrous cap and lipid debris)
Where do most atherosclerotic lesions occur?
Tend to occur at openings of exiting vessels, branch points, POSTERIOR ABDOMINAL AORTA-due to flow disturbances normally seen in these locations
What are the lipids in atheromatous plaques predominantly made of?
Cholesterol and cholesterol esters: These accumulate in the intima, taken up by macrophages and partially oxidized.
When modified LDL (macrophages that take up lipids and partially oxidize them) further accumulates within macrophages and smooth muscle cells to form foam cells, a lesion develops known as ___
“Fatty streak” —> This stimulate an inflamm response to accumulation of this toxic form of LDL
Describe the composition of an atheromatous plaque that forms in the pathogenesis of atherosclerosis:
Fibrous cap: smooth muscle cells, macrophages, foam cells, lymphocytes, collagen, elastin, proteoglycans, neovascularization
Necrotic center: cell debris, cholesterol crystals, foam cells, calcium
List the common sites of involvement of atherosclerosis in descending order:
Abdominal aorta Coronary arteries Popliteal arteries Internal carotids Circle of willis
What are some complications of atherosclerotic plaques?
Rupture and ulceration –> may lead to thrombosis
Hemorrhage–> may follow plaque rupture
Embolism –> may follow plaque rupture
Aneurysm
As a consequence of atherosclerosis, the lumen of the affected vessel gradually shrinks (~70% occlusion), eventually leading to ischemia downstream. This is known as ___
Critical stenosis
May lead to chronic ischemia of myocardium, bowel, brain, the extremities, etc
Describe the lipid core and fibrous cap in a vulnerable atherosclerotic plaque
Vulnerable plaque has a large lipid core and thin fibrous cap which makes the plaque weaker
Conversely, a stable plaque will have a thick fibrous cap and smaller lipid core.
This type of aneurysm is characterized by an intact (but thinned) muscular wall at the site of dilation
True
This type of aneurysm is a defect through the wall of the vessel or heart, communicating with an extravascular hematoma
False
Where are berry aneurysms found? What can they be associated with?
Typically in Circle of Willis
Associated with ADPKD
Rupture can cause fatal hemorrhage
Marfan syndrome can predispose to aneurysm pathogenesis by what mechanism?
Defective FIBRILLIN synthesis –> Defective vascular wall connective tissue
Atherosclerosis weakens the vascular wall by ischemia of the ___
Inner media
HTN weaken then vascular wall by ischemia of the ___
Outer media
Tertiary syphilis weakens the vascular wall by ischemia of the ___
Outer media of the THORACIC aorta
In aneurysm pathogenesis, loss of vascular wall elastic tissue or ineffective elastin synthesis leads to ___ degeneration with disrupted and disorganized elastin filaments and increased ground substance ___
Cystic medial
Proteoglycans
Regarding aneurysm pathogenesis, ___ is a final common result of different conditions, including ischemic medial damage and Marfan syndrome
Cystic medial degeneration
The 2 most important causes of aortic aneurysm are:
Atherosclerosis and HTN
AAA’s are typically due to ___
Thoracic aortic aneurysms are typically due to ___
Atherosclerosis=AAA
HTN=Thoracic aortic aneurysm
AAA’s are more frequent in this population:
Men who smoke and in their 6th decade of life or older
This vascular disorder is characterized by severe atherosclerosis of the aorta, covered with a mural thrombus and may be detected as a pulsating mass in the abdomen
AAA
What are complications of a AAA?
Rupture and hemorrhage
Occlusion of branching arteries and downstream ischemia
Embolism
Impingement of another structure, i.e., vertebral body or ureter
The risk of rupture of a AAA is related to ___
Aneurysm size
Aneurysms >5 cm or greater usually managed surgically
Describe the clinical presentation of a pt with a thoracic aortic aneurysm:
- Impingement of lower respiratory tree, esophagus (difficulty swallowing), recurrent laryngeal n. (Hoarse voice)
- aortic valvular insufficiency
- rupture
Severe chest pain that radiates to the back between the scapulae is the classic clinical presentation of ___
Aortic dissection
Aortic dissection occurs when blood enters a defect in the __ and travels through a tissue plane within layers of the middle portion of the aorta
Intima
What pt population is an aortic dissection likely to occur?
Hypertensive males, 40-60
Pts with disorders of vessel connective tissue (Marfan)
What is the primary risk factor for an aortic dissection?
HTN
Where do most aortic dissections usually arise?
In the ascending aorta
This dissection type involves the ascending aorta, is more common and associated with higher morbidity and mortality
Type A
What is the most common cause of death in an aortic dissection?
Rupture
This disorder is the most common form of vasculitis among older pts and may present with constitutional symptoms. It is characterized by a medial granulomatous inflammation, often with multinucleated giant cells, has fragmentation of the elastic lamina, sites of involvement within an artery may be patchy and focal, and healed sites of inflammation show scarring of the medial and intimal thickening.
Giant cell (temporal) arteritis
Giant cell (temporal) arteritis is due to ___ inflammation of the arteries in the head, especially the temporal arteries
Chronic T cell mediated
Involvement of the ophthalmic a. may lead to vision loss
How do you definitively dx giant cell (temporal) arteritis?
Biopsy of the temporal a. (Should be > 1 cm)
This vasculitis has similar histologic findings to giant cell arteritis but it involves the aortic arch and major branch vessels, the pulmonary, coronary, and renal arteries may be involved, and involves a younger age group (<50).
Takayasu arteritis
A pt with this vasculitis may present with weak pulse and low BP in the UE’s (PULSELESS DISEASE)
Takayasu arteritis
This vasculitis generally involves small-medium sized vessel, is a systemic vasculitis that is likely immune complex-mediated. It classically affects young adults, the renal vessels, heart, liver, and GI tract are involved with sparing of the pulmonary vessels. Almost 1/3 of pts have HBsAg-HBsAb complexes in the involved vessels. Immunosuppressive tx is usually effective
Polyarteritis nodosa
What Ag-Ab complex is associated with Polyarteritis Nodosa?
HBsAg-HBsAb complex
Chronic hep B association
The morphology of this vasculitis is a transmural necrotizing inflammation with neutrophils, eosinophils, lymphocytes and macrophages. There is fibrinoid necrosis of the vessel wall and is non-granulomatous. The sites of inflammation are typically not circumferential and the inflammed vessel wall may become susceptible to thrombus formation/occlusion, aneurysm, or rupture.
Polyarteritis nodosa
This vasculitis is an acute arteritis of infants and small children that often involves the coronary arteries where affected sites may form aneurysms –> thrombosis or rupture –> acute MI. The pt may present with erythema of the conjunctiva, oral mucosa, and palms and soles. The child may have a rash and cervical LN enlargement (mucocutaneous LN syndrome).
Kawasaki disease
Kawasaki disease is usually self-limited and this therapy is indicated to lower the risk of a coronary event:
IVIg and aspirin
This disorder is a necrotizing vasculitis involving arterioles, capillaries, and venules. It commonly affect the vessels of renal glomeruli and lung capillaries. Apoptotic neutrophils (leukocytoclastic vasculitis) and MPO-ANCA are associated with this vasculitis
Microscopic Polyangiitis
Which ANCA is associated with microscopic polyangiitis?
MPO-ANCA
Microscopic polyangiitis is characterized by ___ inflammation with ___ necrosis
Segmental necrotizing inflammation
Fibrinoid necrosis
This disorder is a small vessel necrotizing vasculitis associated with allergic rhinitis, asthma, hypereosinophilia, lung infiltrates, and extravascular granulomas. Many organ systems may be involved.
Chung-Strauss syndrome
In Churg-Strauss syndrome, the inflammation may resemble PAN or microscopic polyangiitis with the addition of ___
Eosinophils and granulomas
This disorder is a vasculitis of small to medium vessels with the clinical triad of aphthous ulcers of the oral cavity, genital ulcers, and uveitis. The vessel inflammation is neutrophilic and morphologically nonspecific and may involve visceral organ systems with subsequent aneurysm formation. There is an association with HLA-B51
Behcet disease (Silk road disease)
HLA-B51 is associate with what vasculitis?
Behcet disease
This disorder is a necrotizing vasculitis featuring the clinical triad of necrotizing granulomas of the upper and/or lower resp tract, necrotizing or granulomatous vasculitis more prominently in the resp tract, and focal necrotizing (often crescentic) glomerulonephritis. It is associated with PR3-ANCA and immunosuppressive tx is usually successful.
Granulomatosis with polyangiitis (Wegeners)
PR3-ANCA is associated with what vasculitis?
Granulomatosis with polyangiitis
Who is most likely to be affected by granulomatosis with polyangiitis?
M>F
Avg age of 40
Most pts have persistent pneumonitis and sinusitis, renal disease, and nasopharyngeal ulceration
Describe the morphology of the Upper Resp tract and Lower resp tract in Granulomatosis with polyangiitis
URT: sinonasal and pharyngeal inflammation with granulomas and vasculitis
LRT: multiple necrotizing granulomas, which may coalesce and cavitate
This disorder is an acute and chronic thrombosing vasculitis of small and medium vessels, especially the tibial and radial arteries. It may lead to vascular insufficiency of the extremities, pts are almost always smokers and young adults, inflammation may extend to involve adjacent veins and nerves (leads to pain), and chronic ulcerations may lead to gangrene.
Thromboangiitis obliterans (Buerger disease)
YOUNG ADULTS WHO SMOKE
Raynaud phenomenon typically involves what parts of the body?
Fingers and toes
What is primary raynaud induced by? Which gender? Is it benign or malignant?
Induced by COLD or emotion; symmetric involvement of digits
Estimated 3-5% of gen pop; YOUNG WOMEN
Benign course
Secondary raynaud is due to what? Is it symmetric or asymmetric? What is the prognosis?
It is a component of another arterial disease such as SLE, SCLERODERMA, or thromboangiitis obliterans
Asymmetric involvement of digits
Worsens with time
What are endogenous and exogenous causes of cardiac raynaud (myocardial vessel vasospasm)?
Endogenous –> epinephrine
Exogenous –> cocaine
This is usually caused by circulating vasoactive agents
This disorder is an abnormal dilation of superficial veins with valvular incompetence, secondary to sustained intraluminal pressure:
Varicose veins
Embolism from thrombi of superficial LE veins is RARE
What are esophageal varices most likely due to and what is the clinical significance?
Portal HTN (often d/t cirrhosis) opens portosystemic shunts which direct blood to veins at the gastroesophageal junction
Esophageal varices are clinically important because they may fatally rupture
An increase in Factor V Leiden increases the risk for ___ formation
Thrombus
What is the single most important risk factor for developing a DVT in the LE?
Prolonged inactivity/immobilization
Systemic hypercoagulability may also increase the risk of a DVT
What is the most serious potential consequence of a DVT?
Pulmonary embolism
Migratory thrombophlebitis (Trousseau sign) is associated with ___
Adenocarcinomas of the lung, ovary, and pancreas
In the classic case, venous thrombosis appear at 1 site, disappear, and reappear at different site
What is the most common hemangioma and what are its features?
Capillary hemangioma
Thin-walled capillaries, tightly packed together
This type of hemangioma has irregular, dilated vascular channels making a lesion with an indistinct border. They are more likely to involve deep tissue, more likely to bleed
Cavernous hemangiomas
This is a type of capillary hemangioma that grows rapidly, often in the oral mucosa (where they may ulcerate)
Lobular capillary hemangioma (Pyogenic granuloma)
-it is NOT pyogenic and is NOT a granuloma
Are hemangiomas benign or malignant?
Benign
This type of lymphangioma appears very similar to capillary hemangiomas but without RBCs. These are subcutis of head/neck and axillae
Simply lymphangioma
This lymphangioma occurs in the neck or axilla of children and can be large. Large ones of the neck are often seen in Turner syndrome (45,X)
Cavernous lymphangioma (CYSTIC HYGROMA)
This is a benign tumor with plump eosinophilic cytoplasm cells that most often appear in distal fingers, are of smooth muscle origin rather than endothelial, and are PAINFUL.
Glomus tumor
Benign tumors arising from GLOMUS BODIES
Bacillary angiomatosis is associated with this gram negative bacteria:
Bartonella bacilli
This neoplasm (not really a neoplasm) is a vascular proliferation in response to Bartonella spp. It occurs on the skin of immunocompromised pts and the lesions are localized forming red papules. Microscopically, a proliferation of capillaries with plump endothelial cells are observed
Bacillary angiomatosis
How do you identify Bartonella spp. in Bacillary angiomatosis?
PCR–> Identifies bacteria
Warthin-Starry stain –> visualize
This intermediate vascular tumor consists of neoplastic endothelial cells that are plump and cuboidal and the vascular channels may be difficult to recognize. It has variable clinical behavior with metastasis in 20-30% of cases. It is difficult to dx microscopically
Epithelioid hemangioendothelioma
Plump and cuboidal cells resemble epithelium
Kaposi sarcoma is caused by ____
HHV8
This clinical form of KS is the most common form seen in the US. It may spread to LNs and viscera
AIDS-Associated
Most common AIDS-associated malignant tumor
This clinical form of KS is of older men from middle eastern, mediterranean or eastern european descent. It is NOT associated with HIV and tumors are localized to skin
Classic KS
This clinical form of KS is NOT associated with HIV, pts <40 yrs old and can involve LNs
Endemic African KS
Has something to do with shoes or not wearing shoes
This clinical form of KS is NOT associated with HIV but rather with T cell immunosuppression. It can spread to LNs and viscera
Transplant-associated KS
Spindle cells are associated with this intermediate vascular tumor:
Kaposi sarcoma
___ is a malignant endothelial tumor that occurs equally in males and female. It may occur most commonly in skin, soft tissue, breast, and liver. It is locally invasive and may metastasize.
Angiosarcoma
What is the prognosis with angiosarcoma?
Bad
5 yr survival around 30%
What is the endothelial marker for angiosarcoma?
CD31
