Vascular Pathology 1 - HTN Vascular Disease, Athero, Aneurysms, Dissection Flashcards
What layer do high pressure arteries have that low pressure veins don’t?
Internal elastic lamina
What is a berry aneurysm? What its rupture cause?
Found in Circle of Willis.
AD PCKD
Rupture = Fatal subarachnoid hemorrhage
What is an AV fistula?
artery»_space; vein.
Commonly due to a developmental defect. May lead to rupture and hemorrhage or to high-output cardiac failure.
What is fibromuscular dysplasia?
Focal thickening of intima and media of med-lg muscluar arteries. Results in stenosis.
What stimuli induce changes in endothelial cell function?
What is the ultimate result?
Stimuli: turbulent blood flow, HTN, complement, bacterial products, viruses, hypoxia, acidosis, tobacco smoke.
Leads to an ACTIVATED STATE
When stimuli are consistently present, the prolonged activated state can lead to ENDOTHELIAL DYSFUNCTION characterized by what three things?
1) Procoagulation
2) Proinflammation
3) Smooth muscle stimulation
What is the stereotypical response to vascular injury?
Intimal Thickening.
How does intimal thickening occur and what is a potential problem with intimal thickning?
Caused by smooth muscle cells from media migrating to the intima and elaborating ECM.
When intima is thickened, potentially AFFECTS BLOOD FLOW.
What are risk factors for essential HTN?
High sodium intake, obesity, stress, smoking, sedentary lifestyle
What normally causes secondary HTN?
Renal or endocrine disorder
What maintains blood volume and vascular tone?
RAS
*Know RAS, aldosterone, ANP function
What vascular morphologic changes occur in HTN?
Hyaline Arteriosclerosis
Hyperplastic Arteriosclerosis
Both result in lumen narrowing
What is Hyaline Arteriosclerosis?
Increased smooth muscle matrix synthesis.»_space;
» Plasma proteins leak across damaged endothelium.»_space;
» PINK (hyaline) thickening of vessel wall and associated lumen narrowing
What is Hyperplastic Arteriosclerosis?
Occurs in severe HTN.
Smooth muscles for concentric lamellations (ONION SKINNING) that result in lumen narrowing.
Onion skinning is associated with what?
The vascular morphologic change associated with Hyperplastic Arteriosclerosis during severe HTN.
What are the three constitutional risk factors associated with atherosclerosis?
Family hx
Age
Gender
What are the four major modifiable risk factors associated with atherosclerosis?
Hyperlipidemia (esp LDL) HTN Smoking DM (other: inflammation, hyperhomocystinemia, metabolic syndrome)
What is the pathogenesis of atherosclerosis?
Chronic injury to endothelium, leading to CHRONIC INFLAMMATION and repair of tissue.
What covers the necrotic core (cell debri, cholesterol crystals, foam cells, calcium) of an atheromatous plaque
Fibrofatty atheroma (soft) with FATTY STREAKS. Covered by fibrous cap (dense collagen fibers, smooth muscle cells, marcophages, foam cells, etc.).
*What is the most common location of atherosclerotic lesions associated with hemodynamic turbulence?
**Openings of exiting vessels, branch points, posterior abdominal aorta.
What are the predominant lipids in atheromatous plaques?
Cholesterol and cholesterol esters.
What secretes IL-1 and why in the inflammatory processes of pathogenesis of atherosclerosis?
Accumulation of cholesterol crystals in macrophages is recognized by inflammasomes and secrete IL-1
What surrounds the necrotic core of an atheromatous plaque?
Zone of inflammatory and smooth muscle cells.
**What are the most common sites of invovlement in atherosclerosis?
**Abdominal aorta > coronary arteries > popliteal arteries > internal carotid arteries > Circle of Willis
