Path: disease of blood vessels Flashcards
1
Q
Congenital anomalies of blood vessels (benign) 1
A
- Vascular malformations: birthmarks, due to errors in vascular morphogenesis (benign), has normal cell turnover/growth
- Capillary malformations (nevus simplex and flammeus): malformed dilated blood vessels that are not cancerous and appear as blotches of red or purple (will involute)
2
Q
Congenital anomalies of blood vessels (benign) 2
A
- Nevus simplex (blanching): single or multiple blanchable pink-red patches, often found on nape of neck and btwn eyes, usually spontaneously disappear
- Nevus flammeus (port-wine stain): usually on head/neck and likes the V1-V3 dermatomes, change from pink to red to purple and do not disappear
3
Q
Hemangiomas of infancy
A
- Bening vascular tumors (non blanching) often on head and neck, looks like red macule that slowly grows over first few months
- 2 phases: first is rapid growth and proliferation over 6-12 mo, then slow involution over several years
- Most follow benign course
4
Q
Venous and arteriovenous malformations
A
- Venous: soft compressible blue masses, pain common and may have venous stasis leading to localized coagulopathy
- AVM: usually in brain but can also be in head and neck, may hemorrhage or lead to seizures, headache or progressive neurological deficit
- AVMs may decrease TPR and lead to increase in SV and CO, which can cause cardiac failure
5
Q
Coarctation of aorta (CoA)
A
- Congenital narrowing of the aorta arising at level of ductus arteriosus/ligamentum arteriosum
- May occur w/ other defects, such as bicuspid Ao valve, Ao stenosis and IV septal defect, berry aneurysms
- 2 types: preductal (infantile) which is more severe (lethal) and less common, and postductal (adult) which is more common and less severe
6
Q
Pre vs postductal coarctations
A
- Preductal: narrowing of aorta is proximal to ductus arteriosus, which remains patent and results in cyanosis of lower half of the body and eventual heart failure
- Postductal: clinically it depends on the degree of narrowing, but the narrowing is distal to the ligamentum arteriosus
- Typically there is hypertension in upper body and weak pulses/hypotension in lower extremities w/ potential ischemia
- Often will see intercostal arteries enlarged which causes erosion of the undersurface of the ribs which causes characteristic x ray findings (rib notching)
7
Q
Hereditary hemorrhagic telangiectasia
A
- Manifests later in life, no Sx at birth
- AVM apparent after birth (incl plum AVM), recurrent epitaxis, mucocutaneous and GI telangiectasias develop progressively w/ age
- Fe deficiency anemia due to hemorrhage
- Dx requirements: epitaxis, telangiectasias, visceral lesions, family Hx
- Commonly associated w/ 2 genes
8
Q
Arteriosclerosis
A
- 3 forms of artery hardening
- Atherosclerosis
- Monckeberg arteriosclerosis
- Arteriolosclerosis
9
Q
Atherosclerosis
A
- Presence of fatty plaque within intima of elastic and muscular arteries
- Can lead to major consequences: aneurysm, MI, CVA, gangrene, etc
- Prominent around site of branching b/c of turbulence
- Fibrous cap overlying soft, necrotic lipid core containing foam cells, lymphocytes, cholesterol crystals
- May have neovascularization of the plaque from the vasa vasorum
10
Q
Complicated atherosclerotic lesions
A
- Focal erosions or rupture of fibrous cap leading to thrombus formation
- Hemorrhage
- Aneurysmal dilation
- Calcification
11
Q
Formation of atheromas
A
- Fatty streaks are precursor, leading to a chronic inflammation of the intima and fibroproliferative process
- Endothelial injury is trigger of inflammation (HTN, hyperlipidemia, DM, smoking)
- Injury is followed by endothelial dysfxn, lowered expression of vasodilatory molecules, increased constriction and pro-inflammatory markers unregulated
- LDL is oxidized and consumed by macs and VSMCs to become foam cells, leading to T cell activation
- VSMCs migrate to surface of intima and contribute to formation of fibrous cap
12
Q
Monckenberg Arteriosclerosis
A
- Ring-like calcifications within the media of muscular arteries
- Ca not associated w/ any inflammation, intima and adventitia unaffected
- Does not narrow the lumen
13
Q
Arteriosclerosis
A
- Arteriosclerotic changes in small arteries and arterioles
- Associated w/ HTN and DM
14
Q
Aneurysms
A
- Pathologic dilation of a blood vessel or wall of the heart
- True vs false lumen: true is where normal blood flow is, false is where stagnant blood flow, often clot, is due to rupture of the intimal and medial layers and blood collecting in adventitia
- Different formations of aneurysms: saccular (spherical dilation), berry (CoW), fusiform (symmetrical dilation of full vessel circumference)
15
Q
Subtypes of aneurysms
A
- Abdominal Ao aneurysms (AAA): most common, usually due to advanced atherosclerosis
- Other causes of AAA: medial degeneration
- AAAs are usually below renal arteries and above ilial bifurcation
- Mycotic aneurysms: infection of vessel wall, usually due to septic embolus from infective endocarditis
- Syphilitic aneurysm: during tertiary syphilis, lesions usually in ascending/thoracic aorta
- Causes arteritis of vasa vasorum leading to ischemia, necrosis of media, dilation of aortic root, and secondary aortic valve incompetence
16
Q
Aortic dissection (AD)
A
- Tear in intima and media leads to blood entering a new false lumen
- Blood pools btwn outer 1/3rd and inner 2/3rds of media, usually in descending (type B) or ascending Ao, or both (type A)
- Rupture of Ao leads to massive hemorrhage
- Blood in false lumen can reenter the true lumen thru a second distal tear (double-barreled)
- Ao regurg, MI, cardiac tamponade (blood in pericardium) and other infarctions are common complications
17
Q
Risk factors of AD
A
- HTN, weakness in Ao wall, male sex
- Atherosclerosis, CT disease (marfan), old age, underlying aneurysm
- Trauma, medical procedures
- Will often see medial degeneration w/ patchy loss of elastic fibers and SMCs replaced by ECM
18
Q
Clinical presentation of AD
A
- Severe, abrupt retrosternal and/or inter scapular pain, described as tearing or ripping or sharp
- Pain may migrate down the back as the dissection progresses
- May see HTN, pulse deficit, SOB, cardiac murmur, or focal neuro deficit (due to infarction)
19
Q
Hypertension
A
- > 140/90, 95% of cases are unknown etiology (essential HTN) and 5% are secondary to something
- Benign HTN: longstanding modest and stable HTN w/o Sx
- Malignant HTN: severe HTN with acute end-organ damage (defined by presence of organ damage and not a certain BP level)
20
Q
Morphologic changes of large arteries in HTN
A
- Large arteries: loss of elastic lamina arrangement w/ fiber thinning, intimal hyperplasia, medial SMC hypertrophy and increased ECM deposition
- Changes result in arteriosclerosis, incl increased stiffness, decreased distensibility and subsequent increase in BP
- Also result in Ao dilation
21
Q
Morphologic changes of small arteries in HTN
A
- Vessels undergo autoregulation, in which VSMCs respond by vasoconstriction to protect capillary perfusion
- Vessels undergo eutrophic or hypertrophic remodeling
- Eutrophic: better form of remodeling, results in smaller diameter but no change in medial cross-sectional area (no growth in wall mass, but vessel shrinks)
- Hypertrophic: worse outcome, due to increase in vessel wall thickness (mostly media) due to hypertrophy and hyperplasia of VSMCs (associated w/ more severe HTN)
22
Q
Other affects of HTN
A
- Endothelial dysfunction and inflammation (from damage) resulting in plaque formation
- Organ damage (mostly heart, brain and kidney) due to narrowing of small blood vessels causing ischemia
23
Q
Benign nephrosclerosis (BN) 1
A
- Associated w/ benign HTN, can see hyaline thickening of vessel walls (due to deposition of plasma proteins and increased basement membrane), known as hyaline arteriosclerosis
- Can see amorphous, glassy pink deposition within the vessels
24
Q
Benign nephrosclerosis (BN) 2
A
- Luminal narrowing and decreased perfusion results in chronic ischemia
- Leads to scarring (chronic process) from tissue damage: patchy tubular atrophy and interstitial fibrosis w/ potential sclerosis (usually very little inflammation
- Grossly, there is lumpy bumpy appearance of kidneys
- Clinically, there is mild renal dysfxn but a higher risk of progression to renal failure
25
Q
Malignant nephrosclerosis (MN) 1
A
- Acute process (associated w/ malignant HTN): non-uniform fibrinoid necrosis, secondary to EC injury
- Inflammation minimal and acute ishcemia/infarction due to diffuse thrombosis
- Healing phase: marked intimal fibrosis (onion-skinning) characterized by concentrically oriented SMCs and ECM deposition
26
Q
Malignant nephrosclerosis (MN) 2
A
- Leads to severe luminal narrowing (hyper plastic arteriosclerosis)
- Grossly, diffuse punctate cortical petechial hemorrhages (flea-bitten appearance)
- Renin levels increase and exacerbate the malignant HTN (often seen in secondary HTN)
27
Q
Vasculitis
A
-Inflammation and damage to vessel walls either due to immune-mediate (most common) or infectious causes
28
Q
Large vessel vasculitis: giant cell arteritis (GCA)
A
- AKA temporal arteritis, is same as takayasu arteritis but GCA is in pts >50 and TA is in pts 70, mainly affects arteries in head (temporal)
- Focal segmental granulomatous inflammation with nodular thickening due to intimal hyperplasia (reduction of lumen)
- Can see multinucleate giant cells and lymphocytic infiltrates, fragmentation of IEL, intimal thickening, medial fibrosis, organization, and thrombosis
- Clinically there are headaches, temporal pain, swelling/tenderness, ocular Sx in 50% of pts
29
Q
Large vessel vasculitis: Takayasu arteritis (TA)
A
- Essentially GCA in pts <50, histologically similar to GCA
- Clinically can affect any organ system
- Primarily a granulomatous vasculitis of the Ao
30
Q
Medium vessel vasculitis: polyarteritis nodosa (PAN) 1
A
- Associated w/ hep B virus, often in young adults
- Localized necrotizing inflammation, favoring bifuctations
- Most commonly affects renal and visceral vessels, but pulmonary circulation is spared
- Lesions can be in many places and at different stages (chronic or acute), can cause mini aneurysm formation
31
Q
Medium vessel vasculitis: polyarteritis nodosa (PAN) 2
A
- Acute lesions: perivascular infiltration of PMNs w/ fibrinoid necrosis, may be able to palpate superficial nodules of aneurysms
- Usually cause intravascular thrombosis and infarction
- Chronic lesions: infiltration of mononuclear cells w/ transmural scarring and thickening which may obliterate lumen
- Highly variable Sx depending on organ system involvement, unRx is bad prognosis
32
Q
Small vessel vasculitis: microscopic polyangiitis
A
- Vasculitis of capillaries, small arterioles and venules
- Can see segmental necrosis of tunica media, but no granulomas (inflammation dominated by PMNs)
- Lesions are all at same time points developmentally
- Lesions can be found in small vessels of lungs
33
Q
Small vessel vasculitis: henoch-schonlein puprpura (HSP) 1
A
- Mostly in children (around 6), multi systemic disease mostly affecting skin, joints, GI, and kidneys
- Due to immune complex deposition (IgA) in vessel walls
- Various inciting agents including URT infections
- Histologically similar to microscopic polyangiitis
- Palpable purport required for Dx, size can vary from pinpoint petechiae to coalescent ecchymoses, usually concentrated on butt and LE
34
Q
Small vessel vasculitis: henoch-schonlein puprpura (HSP) 2
A
- Arthralgias/arthritis second most common Sx, often involving knees, ankles, or feet
- GI Sx, ab pain, vomiting, occult or frank bleeding, nephritis w/ or w/o proteinuria/hematuria possible
- Serum IgA levels elevated in most pts
- Can cause thrombosis but most worried about narrowing of lumen and ischemia due to inflammation/IgA deposition
35
Q
Thromboangiitis obliterans
A
- Almost exclusively in heavy tobacco smokers/users
- Characterized by focal acute and chronic inflammation, thrombosis of medium and small arteries (particularly tibial and radial arteries)
- Often see ischemia and gangrene in extremities
36
Q
Antineutrophil cytoplasmic antibodies (ANCA)
A
-Often associated w/ microscopic polyangiitis and other vasculitis syndromes
37
Q
Raynaud phenomenon (RP) 1
A
- Refers to arterial vasospasm and ischemic changes of the digits in the hands and feet that occur primarily following cold exposure and emotional stress
- Primary RP means Sx occur idiopathically, secondary RP from an underlying source (primary is less severe), both are more prevalent in women
- See sequential color change of the digits (white-blue-red)
38
Q
Raynaud phenomenon (RP) 2
A
- In 1o there’s normal histology in early stages, w/ intimal thickening and thrombus formation in advanced stages
- In 2o theres vascular endothelial damage and corresponding inflammation, w/ more common thrombus formation and hemorrhage
- Pts have sensation of pain, numbness upon ischemia, and pain/throbbing upon reperfusion
39
Q
AIDS associated kaposi sarcoma (KS)
A
- Besides AIDS, long-term immunosuppression can also cause KS
- Most cases associated w/ HHV8
- Gross: multiple red-purple skin plaques or nodules, usually in distal LE
- Histologically: irregular endothelial cell-lined vascular spaces w/ interspersed lymphocytes, plasma cells, and macrophages
40
Q
Angiosarcoma
A
- Rare aggressive neoplasm from either vascular or lymphatic endothelium
- Most often occurs in head and neck, particularly in elderly men
- Associated w/ chemical carcinogens
