Pathology of peripheral vascular disease Flashcards
True aneurysm
Involves all 3 layers of the artery (intima, media and adventitious) or the attenuated wall of the heart)
False aneurysm
Is a wall defect leading to the formation of an extra vascular hematoma that communicates with the intramuscular space “pulsating hematoma)
In a pseudo aneurysm involving the arterial dissections we see pressurized blood gains entry to the arterial wall through
A surface defect and then pushes apart underlying layers
Aneurysms are classified by macroscopic shape and size
- Secular aneurysm
2. Fusiform aneurysm
Spherical outpouchings, ranging from 5 to 20 cm in diameter, involving only a portion of the vessel wall and often contain thrombus
Saccular aneurysm
Diffuse, circumferential dilutions of long vascular segment, put to 2o cm in diameter; these most commonly involve the aortic arch, the abdominal aorta or the iliac arteries
Fusiform aneurysm
The most important predisposing conditions are for an aortic aneurysm:
- Atherosclerosis
- Cystic medial degeneration
- Other conditions that weaken vessel wall such as trauma, congenital defects, vasculitis and infection
Vascular disease develops through two principal mechanisms:
- Narrowing or complete obstruction though either a progressive process like atherosclerosis or an acute event like thrombosis or embolism
- Weakening of vessel walls such as in a dilation or rupture
Diseases of the arterial system
- Atherosclerosis
2. Aneurysms and dissections
Progressive narrowing of the carotid arteries by atherosclerosis leads to Carotid stenosis
Carotid atherosclerosis
Where is the most common site of plaque build up
Bifurcation
carotid stenosis increases the risk of stroke by
- narrowing the artery and reducing blood flow to the brain
- blood clot formation
- plaque deposits rupture and become lodged on a downstream smaller artery
carotid stenosis is asymptomatic or what?
it is asymptomatic and usually the first symptom is a TIA
TIA typically last a couple of minutes and then resolve completely thus they can be ignored
NOOO!
warning sign of an ischemic stroke and permanent brain injury
ischemic stroke symptoms
- drooping face
- vision problems
- difficulty speaking
- paralysis of one side of body
- weakness/numbness in an arm/leg
medications for carotid stenosis
- antiplatelet
- statin
- HTN
surgery for carotid stenosis
endarterectomy, angioplasty and bypass
AAA pathogenesis:
- men or women
- lifestyle risk
- onset
- major cause
- microscopically
- other contributing factors
- positioned
- saccular or fusiform
- frequently contains
- men
- smoking
- 50 yr
- atherosclerosis major cause
- microscopically–> atherosclerosis with destruction and thinning of the underlying aortic media
- hereditary defect or alter balance of collagen degradation and synthesis
- positioned below the renal arteries and above bifurcation of aorta
- either
- contains a laminated mural thrombus
clinical consequences of AAA
- rupture
- obstruction leading to tissue ichemic injury
- embolism
- impingment and compression
syphilitic aneurysm:
- caused
- complication
- tertiary stage
- consequences
- caused by spirocheted T. palladium
- rare complication due to early recog. and tx. of syphilis
- tertiary stage causes obliterative endarteritis of the small vessels
- results in ischemia and dilatation of aorta/aorta annulus and eventually to valvular insufficiency
aortic dissection
blood dissects apart the media to form a blood-filled channel within the aortic wall leading to massive hemorrhage and cardiac tamponade
cardiac tamponade
hemorrhage into the pericardial sac
aortic dissection pathogenesis:
- occurs in older pt. (40-60yr) due to
- occurs in younger patients where they have a
- classifications
- older pt. HTN
- younger pt. connective tissue abn.
- a. type A dissection (proximal) more common and dangerous b/c involves the ascending aorta. DeBakey type I (involves descending aorta) DeBakey type II ( does not involve the descending aorta)
b. Type B dissection—> debarked type III (beginning beyond the subclavian artery.
Is a cerebrovascular disorder in which weakness in the wall of a cerebral artery or vein causes a localized dilatation or ballooning of the blood vessel
Intracranial aneurysm
Intracranial aneurysm
- Lifestyle risk factors
- Genetic conditions
- Classifications (3)
- Aneurysm in the ____ have a higher risk of rupture
- Symptoms
- Treatment
- Prognosis
- Lifestyle risk factors: HTN, smoking alcoholism and obesity
- Genetic conditions: Marian, MEN, AD-PKD, neurofibromatosis
- I. Saccular- berry aneurysm
II. Fusiform- widening of entire artery
III. Microaneurysm- Charcot-Bouchard ( small blood vessel) - Posterior circulation have a higher risk of rupture
- Barely any symptoms— there may be some nausea, vomiting, headache, confusion, loss of consciousness or visual abn.
- Surgical slipping/endovascular coiling or cerebral bypass surgery
- Depends
Diseases of venous system and thrombosis
- Varicose veins
2. DVT
Varicose veins and phlebothrombosis/ thrombophlebitis account for at least ______ of cases of clinically relevant venous disease
90%
Varicose veins
- What is it
- Which veins involved
- Men/ women
- Associates with
- Clinical features
- Abn. Dilated tortuous veins produced by chronically increased intraluminal pressures and weakened wall support
- Superficial veins of the upper and lower leg
- 1/5 men and 1/3 women
- Associates with obesity, compression of the vena cava during pregnancy and there is a familial tendency
- Clinical features— valves become incompetent and leads to thrombosis
DVT:
- Local manifestations
- Common and serious clinical complication of DVT
- Local manifestations— distal edema, swelling and pain (from pressure) Hoffman sign positive
- Pulmonary embolism is the most common and serious complication
Pathogenesis of thrombosis: virchow triad
- Endothelial injury
- Turbulence (abn. Blood flow)
- Hypercoagulability
Risk factors for hypercoagulable states
- Primary (genetic)— factor V mut.
2. Secondary (acquired)— prolonged bed rest, MI, Afib, prosthetic cardiac valve
vasa vasorum associated with
syphilitic aneurysm
most common site of intracranial saccular aneurysm
anterior communicating artery
most common aneurysm in the posterior circulation
basilar artery
