8 - Blood Vessels Flashcards
what are basic constituents of BV
- endothelial cells
- smooth muscle cells
- variety of extracellular matrix
what are the concentric layers of arteries and veins (in to out)
- tunica intima
- tunica media
- tunica externa
what is a single layer of endothelial cells attached to BM and thin underlying layer of ECM
intima
what contains smooth muscle cells and ECM
tunia media
what has LCT and can also contain nerve fibers
tunica adventitia
what is thicker: arterial walls or their corresponding veins
arterial walls
what does atherosclerosis mainly affect
elastic and muscular arteries
what does hypertension affect
small muscular arteries and arterioles
what does vasculitis affect
only vessels of a certain caliper
what causes the blood vessel lumen to decrease
- narrow artery w/ inflammation
- occluded artery with inflammation and scarring
- aneurysm
what is responsible for more morbidty and mortality than any other category of human diseases
vascular path
vascular pathology mainly involves arteries or veins?
arteries (venous disorders are not inconsequential tho)
2 principal mechanisms that underlie vascular disease
- narrowing (stenosis) or complete obstruction of vessel lumina
- weakening of vessel walls
what results in inadequate organ perfusion and can lead to dysfunction or tissue death
hypotension
what can cause end organ damage and is one of the major risk factors for atherosclerosis
hypertension
what is the BP of patients with clinically significant hypertension
> 120/>80
what is the cause of hypertension
largely unknown so called essential hypertension
what is secondary hypertension
10% of patients resulting from underlying renal or adrenal disease, renal artery stenosis, or other identifiable cause
Multifactorial disorder resulting from the cumulative effects of multiple genetic polymorphism and interacting environmental factors
hypertension
does the prevalence and vulnerability of hypertension complications increase w age
yes
is hypertension asymptomatic until late in its course
yes
what happens if hypertension is untreated
- 1/2 die of ischemic heart disease or congestive heart failure
- 1/3 die of stroke
what is malignant hypertension
5% patients show rapidly risking BP that if left untreated leads to death within 1-2 years
what is the BP of severe pressure elevation
> 200/>120
what characterizes malignant hypertension
- severe pressure elevations
- renal failure
- retinal hemorrhages and exudates with or w/o papiledema
Essential hypertension accounts for what percent of cases
90-95% of all cases
secondary hypertension accounts for what percent of cases
5-10% of all cases
what diseases can result in secondary hypertension
- renal
- endocrine
- CVD
- neurologic
blood pressure is determined by ___ and ___
vascular resistance and cardiac output
how is vascular resistance regulated
Vascular resistance is regulated at the level of the arterioles, influenced by neural and hormonal outputs
how is cardiac output determined
Cardiac output is determined by heart rate and stroke volume, which is strongly influenced by blood volume; blood volume in turn is regulated mainly by sodium excretion and absorption
what is a major regulator of BP and is secreted by kidneys in response to decreased BP in afferent arterioles
renin
renin pathway
renin -> cleaves angiotensinogen to angiotensin I -> produces angiotensin II -> regulates BP by increasing vascular SMC tone and by increasing adrenal aldosterone secretion -> increase renal sodium resorption
vascular pathology in hypertension:
[accelerates or decelerates] atherogenesis
causes [formative or degenerative] changes in walls of large and medium arteries that can lead to both aortic dissection and cerebrovascular hemorrhage
accelerates; degenerative
what is the hardening of arteries, generic term for arterial wall thickening and loss of elasticity
arteriosclerosis
what are the general patterns of arteriosclerosis? what does it affect?
- arteriolosclerosis - small vessels
- Monckeberg medial sclerosis - middle layer
- fibromuscular intimal hyperplasia - inner layer
- atherosclerosis - medium and large vessels
Arterioles show homogenous, pink hyaline thickening with associated luminal narrowing; these changes reflect both plasma protein leakage across injured epithelial cells and increased smooth muscle cell matrix synthesis in response to the chronic hemodynamics pressure of HT. what is this
hyaline arterioslcerosis
vessels of older patients frequently exhibit hyaline AS, it is most generalized and severe in patients with ___ and ___
hypertension and DM
hyperplastic AS occurs in what
severe HT
what has vessels that exhibit concentric laminated (“onion skin”) thickening of walls with luminal narrowing. Laminations consist of SM cells with thickened, reduplicated BM
hyperplastic arteriolosclerosis
when is hyperplastic AS accompanied by fibrinoid deposits and vessel wall necrosis
malignant HT
what is characterized by calcifications of medial walls of MUSCULAR arteries
monckeberg medial sclerosis
who is affected by monkceberg medial sclerosis
adults > 50
do calcifications enroach vessel luman in Monckebeg Medial Sclerosis? are they clinically significant?
do not encroach and are not clinically significant
what is this:
- Occurs in muscular arteries larger than arterioles
- It is driven by inflammation or by mechanical injury
- Can be considered a healing process
fibromuscular intimal hyperplasia
what is an intimal based lesion composed of fibrous capsule and an atheromatous core
atherosclerosis
what are present in the plaque of atherosclerosis
The constituents of the plaque include smooth muscle
cells, extracellular matrix, inflammatory cells,
calcifications, lipids, and necrotic debris
in atherosclerosis, do plaques develop and grow quickly or slowly
slowly over decades
atherosclerosis is driven by interplay of __ and ___
vessel wall injury and inflammation
what can produce symptoms related to chronic ischemia by narrowing vessel lumsn
stable plaques
what can produce fatal ischemic complications related to acute plaque rupture and embolism
unstable plaques
atherosclerosis underlies the pathogenesis of what diseases
- coronary
- cerebral
- preipheral vascular disease
nonmodifiable risk factors for atheroscelrosis
- genetic abnormalities
- family history
- increasing age
- male gender
what are modifiable risks for atherosclerosis
- hyperlipidemia
- hypertension
- cigarette smoking
- diabetes
- inflammation
major consequences of atherosclerotic diseases
- myocardial infarction (heart attack)
- cerebral infarction (stroke)
- aortic aneurysm
- peripheral vascular disease (gangrene of legs)
what are the major targets of atherosclerotic diseases
- large ELASTIC arteries (aorta, carotid, and iliac arteries)
- large-and medium-sized MUSCULAR arteries (coronary and popliteal arteries)
atherosclerotic plaques progress from ___ to a ___ leading to either erosion or rupture of thin-capped fibroatheroma
fatty streak to classic atheroma
how do atheromas cycle
between healing, thrombosis and finally to blockage of the concerned artery
T/F: there could be multiple cycles of healing and rupture of atherosclerotic plaques before an artery is blocked
TRUE
what do atherosclerotic plaque consist of
extracellular lipid particles, foam cells, and debris that have accumulated in the intima of arterial wall and form a lipid or necrotic core
what is the core of atherosclerotic plaque surrounded by? covered by?
surrounded by layer of collagen-rich matrix and smooth muscle cells
covered by endothelial cells called fibrous cap
what is a localized abnormal dilation of BV or heart that may be congenital or acquired
aneurysm
what aneurysm involves all layers of intact arterial wall of thinned ventricular wall of the heart
true aneurysm
what aneurysm is a defect in the vascular wall leading to extravascular hematoma that freely communicates with intravascular space “pulsating hematoma”
false aneurysm (pseudoaneurysm)
what are the 2 most important causes of aortic aneurysms
- atherosclerosis
- hypertension
who has aneurysms
men over 50 and smokers
aneurysm complicates are related to what
- rupture
- thrombosis
- embolism
what occurs when blood separates the laminar planes of the media to form a blood-filled channel within the aortic
dissections
aortic dissections are generally associated with what
aortic dilation
it can be disatrous if dissections rupture thru what
thru adventitia and hemorrhage into adjacent spaces
who has aortic dissections
- men aged 40-60 years with antecedent hypertension (MOSTLY)
- younger patients with syndromic diseaes affecting aorta (Marfan syndrome)
an aortic dissection may lead to ___ ; such a massive amount of hemorrhage can lead to cardiac tamponade
hemopericardium when blood dissects thru media proximally
what is a general term for vessel wall inflammation and is frequently associated w/ systemic manifestations and organ dysfunction
vasculitis
what are 2 pathogenic mechanisms of vasculitis
- immune-mediated inflammation (sterile)
- direct invasion of vessel wall by infectious pathogens (insterile)
what is the chronic, classically granulomatous inflammation of large-
to small-sized arteries that principally affect arteries in the head (T-cell immune response)
giant cell (temporal) arteritis (GCA)
what is the most common form of vasuclitis among elderly adults
GCA (temporal)
what vessels are involved in GCA
opthalmic, vertebral, and aorta
are temporal arteries vulnerable in GCA?
no but name is in disorder because they are the most readily biopsied in making the diagnosis
symptoms of GCA
- vague and constructional
- facial pain and headache
- most intense along course of superficial temporal artery which is painful to palpation
GCA diagnosis is based on what
biopsy and histologic confirmation
is GCA extremely focal within an artery
YES!
adequate biopsy of GCA requires what
1 cm segment
treatment of GCA
corticosteroids and anti-TNF therapies
what vasculitis can cause lingual necrosis
GCA (temporal)
what is takayasu arteritis also called
pulseless disease
what is granulomatous vasculitis of large- and medium- sized arteries characterized principally by ocular disturbances and marked weakness of pulses in the upper extremities
Takayasu arteritis (pulseless disease)
what is the transmural fibrous thickneing of aorta-particularly of the aortic arch and great vessels resulting in severe luminal narrowing
Takayasu arteritis (pulseless disease)
what age of ppl with takayasu arteritis
under age 50
what shares the same clinical and histologic features of GCA except for age?
Takayasu Arteritis
what is the likely etiology of takayasu arteritis
autoimmune
what disease:
Initial symptoms are usually nonspecific (fatigue, weight-loss, fever); with progression, vascular features dominate (reduced BP and weaker pulses in the upper extremities, ocular disturbances and total blindness, and neurological deficits
takayasu arteritis
takayasu arteritis involves what portion of the aorta? what does this leads to?
distal aorta leading to claudication of the legs
pulmonary artery involvement in takayasu arteritis leads to what
pulmonary hypertension
renal artery involvement in takayasu leads to what
systemic hypertension in 1/2 of patients
takayasu arteritis is mainly [lower extremities OR upper and head]
lower extremities
GCA is mainly [lower extremities OR upper and head]
upper and head
Systemic vasculitis of small- or medium-sized muscular arteries that typically affect renal and visceral vessels but SPARES PULMONARY CIRCULATION
polyarteritis nodosa (PAN)
clinical manifestation of PAN result from what
ischemia and infarction of affected tissues and organs
PAN is often associated with what
transmural necrotizing inflammation often w/ superimposed aneurysms and thrombosis
what age does PAN o ccur
young adults (younger than 50)
is PAN requently remitting and episodic with short symptom-free intervals?
NO!! PAN is frequently remitting and episodic with LONG symptom free intervals
what has a typical presentation of rapidly developing HT due to renal artery involvement, abdominal pain and bloody stools caused by vascular GI lesions, diffuse myalgia, and peripheral neuritis
PAN
what is the major cause of PAN mortality
renal involvementi
is untreated PAN fatal
yes
immunosuppression of PAN can yield remission in ___% cases
90%
what is an acute, febrile, usually self-limiting illness of infancy and childhood associated w/ large to medium sized vessel arteritis
kawasaki disease
who gets kawasaki disease
80% <4 years old
clinical significance of kawasaki disease stems from what
invovlement of coronary arteries
in ___ people, a variety of infectious agents (mostly viral) have been positioned to trigger kawasaki
genetically susceptible people
what disease:
Presents with conjunctival and oral erythema; blistering edema of hands and feet; erythema of palms and soles; desquamative rash; cervical LN enlargement
Kawasaki disease
20% of untreated patients with kawasaki disease develop waht
cardiovascular signs and symptoms resulting in asymptomatic coronary arteritis, to giant coronary artery aneurysms
aneurysms associated w/ Kawasaki disease are associated with what
- rupture
- thrombosis
- MI
- sudden death
kawasaki disease tx
IV immunoglobulin therapy and aspirin
granulomatosis with polyangitis was previously called what
Wegner granulomatosis
granulomatosis w/ polyangitis (GPA) is a necrotizing vasculitis characterized by what
- acute necrotizing granulomas of upper or lower respiratory tract
- necrotizing granulomatous vasculitis of small to medium size vessels (PROMINENT IN LUNGS)
- glomerulonephritis
who has GPA
> males, average age of 40 years
what are classic features of GPA
- bilateral pneumonitis (w/ nodular and cavitary lesions) (MAIN)
- chronic sinusitis
- mucosal ulceration of nasopharynx
- renal disease
- (also: rashes, myalgia, articular involvement, neuritis, and fever)
if GPA is untreated, what happens
disease become rapidly fatal w/ 80% mortality within 1 year
what are the most fatal of noninfectious vasculitis
PAN and GPA
what features strawberry gingivitis
GPA
what disease:
Characterized by segmental, thrombosing, acute and chronic inflammation of medium- and small-sized arteries, especially the tibial and radial arteries, that often lead to vascular insufficiencies, typically of the extremities
thromboangiitis obliterans (Buerger disease)
thromboangiitis obliterans is also called what
buerger disease
who has buerger disease
heavy cigarettes smokers usually before the age of 35
people who smoking really like eating burgers
early manifestations of buerger disease
- Raynaud phenomenon
- instep foot pain (induced by exercise)
- superficial nodular phlebitis
Buerger disease has vascular insufficiences that are acocmpanied by what? why?
accompanied by severe pain (even at rest) due to neural involvement
chronic extremity ulcerations of Buerger disease can progress over time to become what
frank gangrene
can smoking abstinence in early stage of Buerger disease prevent further attacks
yes
once Buerger disease is established, will smoking abstience help?
no - vascular lesions no longer respond to abstience
what causes infectious vasculitis
direct invasion of infectious agents (usually bacteria or fungi)
what species of bacteria or fungi cause infectious vasculitis
- Aspergillus
- Mucor
is infectious vasculitis invasion mostly local or systemic?
localized tissue invasion (bacterial pneumonia)
less commonly, how does infectious vasculitis spread
hematogenous spread of microorganisms during septicemia or embolization from infective endocarditis
in what vasculitis are vessels weakend and culminate in mycotic aneurysms or thrombosis and dowards infarction
infectious vasculitis
what results from exaggerated vasoconstriction of arteries and arterioles in response to cold or emotion
raynaud phenomenon
what does Raynaund Phenomenon affect
extremities (fingers and toes)
occasionally nose, earlobes, or lips
restricted blood flow in raynaud’s induces what
paroxysmal pallor and cyanosis
color changes in raynaud
whte -> blue -> red
who does primary raynaud phenomenon affect? where?
> in young women; occurs symmetrically in the extremities; severity and extend of involvement does not progress
what does secondary raynaud phenomenon refer to
vascular insufficienes (unkown cause) due to arterial disease cuased by other entities (SLE, scleroderma, Buerger, or atherosclerosis= BASS)
is primary or secondary raynaud symetric?
primary is symmetric
secondary is asymmetric
T/F: 10% of patient with Raynaud Phenomenon manifest an underlying disorder
TRUE
what is another name for thrombophlebitis
phlebothrombosis
what are abnormally dilated, tortuous veins produced by prolonged, increased intraluminal pressure with vessel dilation and incompetence of venous valves
varicose veins
what veins are commonly involved in varicose veins? why?
superficial veins of upper and lower legs bc venous pressure by prolonged dependent pressure
who gets varicose veins
20% men and 1/3 of women
what increases risk of varicose veins
obesity
incompetence of venous valves due to variicose veins lead to what
stasis, congestion, edema, pain and thrombosis
what occurs from chronic venous congestion and poor vascular draininage leading to congestion dermatitis and ulceration
secondary tissue ischemia (in relation to varicose veins)
what are the 3 causes of esophageal varices
- liver cirrhosis
- portal vein thrombosis
- hepatic vein thrombosis
portal HT leadgs to opening of portosystemic shunt that increases blood flow to what structures? what does this form?
- gastroesophageal junction -> forms esophageal varices
- rectum -> forms hemorhoids
- periumbilical veins of abdominal walls -> forms Caput medusa
___ are the most important varices since their rupture can lead to massive (fatal) upper GI hemorrhage (aka the most problematic)
esophageal varices
what relieves the high BP in the portal vein that often occurs in the setting of liver cirrhosis
portosystemic shunt
___ allows blood flowing into the liver from the portal vein to flow through the ___ directly into the hepatic vein, the vein that drains blood out of the liver to the vena cava and then immediately into the heart.
portosystemic shunt; portosystemic shunt
are deep vein thrombosis most of the cases?
yes! 90%
decreased blood flow in the setting of prolonged immobilization is the most common cause of what
lower extremity deep vein thrombosis
examples of things that cause thrombophlebitis/phlebothrombosis
extended bed rest, sitting during long airplane, automobile excusions
risk factors of thrombophlebitis and phlebothromobsis
pregnangy, oral contraceptive use, obesity, CHF and malignancy
diferent between thromblophlebitis and phlebothrombosis
thrombophlebitis = clot AND inflammation
phlebothrombosis = clot only NOT inflammation
what is a serious complication of DVT resulting from detachment or fragmentation of venous thrombi
pulmonary embolism
what represents acute inflmmation caused by spread of bacterial infection into lymphatics
lymphangitis
what is the most common agent of lymphangitis
group A beta-hemolytic streptococcu
what happens to affected lymphatics in lymphangitis
lymphatics are dilated and filled w exudate of neutrophils and monocytes
manifestations of lymphangitis
Manifested as red, painful subcutaneous streaks with
painful enlargement of the draining lymph nodes
(lymphangitis)
what is build-up of fluid in soft tissues when the lymph system is damaged or blocked
lymphedema
secondary causes of lymphedema
Tumors
Surgical procedures
Post radiation fibrosis
Filariasis
Post inflammatory thrombosis or scarring
what are benign neoplasmic vascular tumors
- hemangioma
- lymphangioma
what are immediate grade neoplasmic vascular tumors
kaposi sarcoma
what are malignant neoplastic vascular tumors
angiosarcoma
what is a very common benign tumor composed of blood filled vessels. It is 7% of all benign tumors of infancy and childhood. most are present at birth and initially increase in size but eventually regress spontanteously
hemangioma
where are hemangioma lesions
typically on head and neck and thoracic skin, but can also arise internally
1/3 of internal lesions are in LIVER
is malignant transofmration of hemangioma common?
NO! rare
what is a benign tumor of lymphatic vessels
llymphangioma
what i a cystic lymphangioma most commonly occuring in head and neck and axilla of an infant
cystic hygroma
what is the most common intraoral site of lymphangioma
tongue
what is malignant neoplasm of endothelial cells caused by human herpesvirus 8 (HHV 8; AKA KS herpesvirus)
kaposi sarcoma
kaposi sarcoma is common in patients with what
AIDS
4 classical presentations of Kaposi sarcoma
- classic
- endemic (african)
- epidemic (AIDS related)
- iatrogenic (transplant associated)
what are the 3 stages of kaposi sarcoma
patches (red-purple macules), raised plaques and eventually nodular lesions
what is angiosarcoma? who gets it?
Malignant neoplasm of endothelial cells
>older males and females
where does angiosarcoma occur
Can occur at any site; > in skin, breast, and liver
Can also arise in the setting of lymphedema (in
ipsilateral upper extremity several years after radical
mastectomy for breast Ca
what is angiosarcoma induced by
radiation
is angiosarcoma locally invasive and can readily metastasize
yes
what is the survival rate of angiosarcoma
5 year ~30%
