aneurysm artries Flashcards
Arteries:
* large elastic
— , —, —
* Medium sized, muscular
— & — arteries
* Small (<2mm)
Course within — and —
Arterioles:
* — branches of arteries - – µm
* Small changes in — size (Vasoconstriction) causes — flow- —effect - resistance is — proportional to — power —
* Principal area of physiologic —- to blood flow
* Bear the brunt of effects of —-
aorta,cartoid,iliac
coronary & renal artries
tissues and organs
smallest
20-100
lumen
profound
limiting
inversely
fourth
radius
resistance
hypertension
CAPILLARIES
* – walls (— thick)
* Capillary bed has —
cross-sectional area
* – flow
* Ideal conditions for —
between blood and tissue e.g. in lungs
Veins:
* — caliber
* — walled
* – systemic blood in — circulation
* — support - therefore liable to:
Irregular— –> — veins in legs
Penetration by —
Valves prevent — flow
Vasodilation causes — /A —
Lymphatics:
*—-walled, —-lined channels
* No — cells
* — system for returning — tissue fluid to—
* Important pathway for disease—
thin
1 cell
large
slow
diffusion
large
thin
2/3
venous
poor
dilitation –> varicose
tumours
reverse
hypotension/a faint
thin
endothelium
blood
drainage
interstitial tissue to blood
dissemination
main diseases processes of artries:
1- — of large arteries with
occlusion
Dilatation/Aneurysm/Rupture/Dissection
* Small arteries
* — changes
* — i.e. Arteritis which might be causes by immune complex as SLE , ANCA , antibody attack as good pasture syndrom , cell mediated by allograft organ rejection
atheroma
hypertensive
inflammatory
vasculitis:
- —- process → — of & — to blood vessels
- — compromised → — of tissues supplied by
involved vessels
1- General:
* Any type, size, & location of
vessel
* Disease Expression Varies
* Genetic predisposition
* Environmental exposures
* Regulatory mechanisms
associated with immune
response to antigens
2- Pathophysiology/Pathogenesis:
* Pathogenic Immune complex
formation / deposition
* Production Anti Neutrophilic
Cytoplasmic Antibodies
* Pathogenic T-Lymphocyte
Response & Granuloma
Formation
clfinicopathologic process
inflammation and damage
lumen
ischemia
- immune complex vasuclatitis formation/depostion:
- – vasculitis (Henoch
Schönlein) - – vasculitis
- — sickness & — vasculitis
syndromes - HCV - associated
cryoglobulinaemic vasculitis - HBV - associated vasculitis
- ANCA aka anti neutrophil cytoplasmic autoantibody and vasuclartis:
- ANCAs = a group of – detected in a number of — disorders, but particularly associated with — vasculitis
- Main classes
– —
– — - 3 primary vasculitides associated with ANCA positivity:
– — with Polyangiitis (Wegener’s granulomatosis) [90%+]
– — Polyangiitis
– — granulomatosis with polyangiitis (Churg Strauss)
-Active granulomatosis with polyangiitis in the absence of —
Absolute height of antibody titres does not correlate well with disease —
Granulomatosis with polyangiitis in remission may continue to have – ANCA levels for years
IgA
lupus
serum and cutaneous
autoantibodies
autoimmune
systemic
p-anca
c-anca
( info: Myeloperoxidase: elastase, cathepsin G, lactoferrin, lysozyme, Bactericidal / permeability
increasing protein, Proteinase3:, a 29kDa neutral serine proteinase
present in neutrophil azurophilic granules)
granulomatosis
microscopic
esotinophilic
ANCA
activity
high
pathogenic t lymphocyte response:
* — cells [ECs]can express – molecules following activation by— such as interferon (IFN) γ.
Allows EC’s to participate in— reactions such as interaction with — in a manner similar to antigen presenting
macrophages
* ECs can secrete — which
may activate — s & initiate/ propagate — immunologic processes within the blood vessel
* — & — potent inducers of
ELAM1 & VCAM1 which may
enhance— of – to ECs in vessel wall
endothelial cells
human leukocyte antigen HLA class ii
cytokines
immunologic
cd4+ t lymphocyte
interleukins
t lymphocyte
in situ
IL1 and TNF alpha
adhesion
leukocyte
1- GRANULOMATOSIS WITH POLYANGIITIS – GPA (OLD TERM WEGNER’S DISEASE)
-UPPER & LOWER RESPIRATORY TRACTS WITH GLOMERULONEPHRITIS & VARIABLE DEGREES OF DISSEMINATED VASCULITIS:
* — vasculitis — &— with — formation
– Intravascular or extravascular [rare on renal biopsy]
* Any organ can be involved with vasculitis, granuloma, or both
– ENT 73% →93%; Lung 45% → 85%;
Renal 77%
* — production from peripheral blood — and — cells ↑
* 90% positive —
* At Biopsy Midline Destructive Disease
Beware:
– Extranodal natural killer (NK) / T-celllymphoma (nasal type)
– Cocaine [+/- levamisole adulteration] induced tissue injury
– Lymphomatoid Granulomatosis [EBV]
– Effects of Pre-biopsy treatment
necrotising
small artries and veins
granuloma
TNF alpha
mononuclear cells
cd4+ T cells
anti-proteinase 3 ANCA
- microspcoic polyangiitis :
a — vascularitis w — and w few or no — complexes affecting the small vessels ( capillaries , venues , arterioles) - its very similar to granulmatosis w polygiitis
- golmerulanphritis 79%
- hameotpysis 12%
- skin nerves gut
- ANCA 75%[Myeloperoxidase]
- estiniphlic graulmatosis w polygiitis ( churg strauss ) ASTHMA, PERIPHERAL & TISSUE EOSINOPHILIA,EXTRAVASCULAR
GRANULOMA FORMATION
& VASCULITIS OF MULTIPLE ORGAN SYSTEMS: - Asthma, Pulmonary Infiltrates,
Mononeuritis Multiplex - – & —
- Eosinophilia, which reaches
levels >1000 cells/μL in >80% of
patients - 48% of patients have circulating
ANCA, usually —
narcotising
no granulomas
immune
skin and heart
anti-myeloperoxidase
polyarteritis nodosa:
MULTISYSTEM, NECROTIZING VASCULITIS OF SMALL &
MEDIUM SIZED MUSCULAR ARTERIES [ — AND — ARTERIES CHARACTERISTIC]
* Does not involve —
– — vessels may be involved;
* No — , significant — or —
* Vessel involvement segmental involve —
* May spread — to involve adjacent veins
* Histopathology – — dependant
– Acute:
* — infiltrate all layers of the vessel wall & perivascular areas
* intimal— and — of vessel wall
– Subacute:
* — cells infiltrate as — progress to
– Chronic stages:
* — necrosis of the vessels ensues
with compromise of the —, — , — of the tissues supplied by the involved vessel +/- — .
– Healing Stage:
* — deposition, which may lead to
further – of the vessel lumen.
* — up to 1 cm in size along the involved arteries are characteristic of polyarteritis nodosa.
renal and visceral
pulmonary artries
bronchial vessels
granulomas , estinophilia , allergies
bifurcations
circumferentially
time
polymorphonuclear neutrophilis
intimal proliferation and degeneration
mononuclear cells
lesions
fibrinoid
lumen, thrombosis , infraction
haemorrhage
collegen
occlusion
Aneurysmal dilations
giant cell arteritis and polymylagia rheumatica :
1- temporal arteritis:
— of – & – sized —
* 1+ branches — artery particularly — artery
* — disease that may involve arteries in — locations, particularly the — and its – branches
* Association with —
2- polymylagia rheumatica:
* Stiffness, aching, and pain in the
muscles of the neck, shoulders,
lower back, hips, thighs
* Occurs in — , but may be
seen in 40–50% of patients with—
* ~10–20% of patients who initially
present with features of isolated
PMR later go on to develop giant
cell arteritis
* Increased expression in the — of —
* Protein recognized by — →induces — &— polarization
* — producing TH1 cells
and — producing TH17
cells
inflammation
medium and large sized arteries
cartoid
temporal
systemuc
multiple
aorta and main branches
HLADR4
isolation
giant cell arteritis
endothelium
jagged 1
cd4+
th1
th17
IFNy
IL17
- takayasu’s arteritis :
1- — vessel walls, stenosis, post-stenotic dilation, aneurysm formation, occlusion
2- — collateral circulation
3- Complete imaging of the aorta & major branches essential
4-Tissue for diagnosis rarely available
5- Exclude — related disease [potential cause of aortitis &
periaortitis ]
6-IgG4 positive plasma cells, storiform pattern of fibrosis, obliterative phlebitis - IGA vascualritis ( henoch scholein ) :
- IgA immune complex deposition
- Precipitants
– —- respiratory tract
infections,—,—, insect—,— - Symptoms
– —
– Abdominal –
– — [ Glomerulonephritis ] - ↑ IgA ~—
irregular
increased
IgG4
upper ,drugs ,food,insect bites , immunisation
arthralgia
abdominal pain
urinary
50%
cryoglobulinaemic vasuclartis:
* – precipitable — - — immunoglobulins
* Hepatitis C, multiple myeloma,
lymphoproliferative disorders,
connective tissue diseases,
infection, liver disease, idiopathic
– — antigens in vasculitic skin
lesions,
– Effectiveness of — therapy
– Hep C RNA & anti–Hep C
antibodies in serum
cryoprecipitates
* Immune Complexes
– Hep C antigens, polyclonal Hep
C– specific IgG & monoclonal
IgM rheumatoid factor
* — 90% of patients
cold
mono/polycolonal
hep c
antiviral
Hypocomplementemia
single organ vasculartis:
rule out systemic disease
NERVOUS SYSTEM [ CNS
PNS ]
* Primary V Secondary
* PNS More likely to be —
* BUT exclude CNS
complications of long
term immunosuppressive
therapy
* Primary CNS vasculitis
- primary SNS vasulitis PCNSV diagnosis difficult:
Problem
* No Recognisable clinical syndrome
* No accepted diagnostic criteria
* No biochemical, immunological,
serological, imaging investigations
diagnostic of PCNSV
* No Diagnostic Test other than Biopsy
– Catheter Angiography Sens & Spec
25- 35% !
* Test to :-
– Exclude alternative inflammatory,
autoimmune, infective, malignant
disorders
– Identify clinically occult systemic
involvement & accessible targets for
biopsy
- angio neg - biopsy pos
2ndary
brain biopsy - pre biopsy planning:
* Meninges
* Block – cm 3
* Crest of a Gyrus
* White Matter
* — Post
Biopsy
* Unlikely to have
enough for IF
- peripheral nerve vasculitis:
* Is the nerve clinically
involved ?
* Multiple levels
*— your Diagnostic
Threshold for Vasculitis
1
coagulant
lower
vadulitis mimic clinical and pathological :
* Infectious Diseases
– Bacterial endocarditis
– Disseminated gonococcal
infection
– Pulmonary histoplasmosis
– Coccidioidomycosis
– Syphilis
– Lyme disease
* Neoplasms
– Atrial myxoma
– Lymphoma
– Carcinomatosis
* Coagulopathies / Thrombotic
Microangiopathies
– Antiphospholipid
syndrome
– Thrombotic
thrombocytopenic purpura
* Drug Toxicity
– Cocaine
– Levamisole
– Amphetamines
– Ergot alkaloids
– Methysergide
– Arsenic
- Others
– Sarcoidosis
– Amyloidosis – see Brain
– Lymphomatoid
Granulomatosis
– Atheroembolic disease - Fibromuscular
dysplasia
– Heritable disorders of
connective tissue
– Segmental arterial
mediolysis (SAM)
– Reversible cerebral
vasoconstrictive
syndrome – see [CNS]
infectious arteritis:
* is —
* — invasion of infectious agents
* — /—
* Weaken arterial wall and may lead to— ( – caused) —
* Induces — - — of tissue - spread of —
What are the consequences of arteritis:
* — and—
* —
* – and—
* How do we commonly treat an arteritis?
localosed
direct
bacteria /fungi
mycotic
infection
aneurysm
thrombosis
infraction
infection
thrombosis and occlusion
aneurysm
rupture and haemorrhage
aneurysm:
* A – abnormal — of a blood vessel
* Types: True or false
True- bounded by – components or the — wall of the –
False- a breach in the — wall leading to an — that freely communicates with the — space e.g.
Following —
causes:
* Atherosclerosis– abdominal aorta, iliac arteries
* Congenital defects – berry aneurysm in Circle of
Willis
* Infections (mycotic aneurysm)
* Trauma
* Cystic medial degeneration
* Systemic diseases e.g. vasculitis
* Syphilitic (luetic)
localised
dilation
arterial wall
attenuated
heart
vascular wall
extravascular hematoma
intravascular space
trauma
abdominal aortic aneurysm:
* Usually positioned – the — and – thebifurcation of the — – – , —
* Types: — or —
* Can be up to 15 cm in greatest diameter and of variable length
* The risk of repture is directly related to the – of the aneurysm > – cms
* Important clinical factor affecting aneurysm growth is —
- clinical consequences:
— into the peritoneal cavity or retroperitoneal tissues with massive, potentially fatal, haemorrhage
— of an artery (iliac, renal, mesenteric, or vertebral branches that supply the spinal cord)
leading to ischemic tissue injury or infarction
— from atheroma or mural thrombus
— on an adjacent structure, such as compression of a ureter or erosion of vertebrae
Presentation as an abdominal – (often palpably
pulsating) that simulates a tumour
below
renal artires
above
aorta
atheroma , hypertension
saccular or fusiform
size
>5 cm
blood pressure
rupture
obsutrcuton
embolism
impingement
mass
thoracic aortic dissection not related to atheroma:
*– in the – allows – of blood between and along the laminar planes of the—, resulting in the formation of a — -filled — within the —
* Can rupture — , causing massive—
* May or may not be associated with —/–of the aorta (Avoid term dissecting aneurysm)
causes:
* More than 90% of dissections occur in— between the ages of— and— with antecedent —
* Systemic or localised abnormality of —that affects the aorta (e.g. Marfan syndrome)
* — , as a complication of —
tear
intima
dissection
media
blood
channel
aortic wall
outwards
haemorrhage
dilation /aneysm
men
40 and 60
hypertension
connective tissue
iatrogenic
artial cannulation
clinical symptoms of thoracic aortic dissection:
* Clinical symptoms
Sudden onset of excruciating pain, usually beginning in
the anterior chest, radiating to the back, and moving
downward as the dissection progresses
* Complications depend on the level of the aorta affected
Most serious complications occurring from the aortic
valve to the arch haemopericardium
Main cause of death is rupture of the dissection outward
patient profile:
- Men 40 - 60
> 90% hypertensive
Cause: Cystic medial degeneration - Younger
Systemic or localised abnormality of connective tissue
(Marfan’s)
Cystic medial degeneration - Complication of arterial cannulation
- Pregnancy
- syphilitc aneurysm:
- — aorta
- Rare in — era
- Tertiary syphilis
- Aortitis
- Damage to— necrosis
- – of wall - aneurysm
- berry aneurysm:
- is —
- Most common type of — aneurysm
- Genetic or acquired
- Arise around circle of Willis
- 90%—
- Multiple in 20 - 30%
- If rupture cause subarachnoid —
- Sporadic
Risk factors - Genetic
Polycystic kidney
disease
Ehlers-danlos
Marfan’s - Smoking
- Hypertension
ascending
antibiotic
vasa vasorum
weakening
saccular
intracranial aneurysm
anterior
haemorrhage
capillary micronaeysm:
* Associated with — in – and — if they rupture
* Associated with— haemorrhage in—
hypertension
brain and intracerebal
retinal
diabetics
