01b: Atherosclerosis Flashcards
Which vessels are favored sites of atherosclerosis/atheroma formation?
- Abdominal aorta
- Coronary aa
- Carotid aa
- Popliteal aa
Atherosclerosis: intimal lesion composed of which cell types?
Endothelial, smooth muscle, macrophages, inflammatory cells
T/F: Lipid found in atheroma is mainly cholesterol.
False - cholesterol esters
What’s a “fatty streak”?
Accumulation of foam cells in the intima
Rupture of plaque is more likely in atheromas with which main characteristics?
- Large lipid core (over 40% of atheroma volume)
2. Thin fibrous cap (with little smooth muscle)
Complications of atherosclerosis:
- Calcification
- Hemorrhage
- Rupture/erosion
- Embolization
Arterial stenosis: a “significant” lesion is reduction by (X)% of diameter and symptoms (present/absent) at rest.
X = 50-70
Absent (symptoms upon exertion)
Arterial stenosis: a “critical” lesion is reduction by (X)% of diameter. (Y)% stenosis will reduce resting flow.
X = 75+ Y = 90+
Risk factors for atherosclerosis.
- Diabetes
- Hyperlipidemia
- HT
- Smoking
- Male sex
- Age
- Genetics
What’s a “false” aneurysm?
A psueudo-aneurysm; outpouching of blood vessel (not widening of the original vessel)
Histopathology of MI: 1-3h from infarction.
Wavy fiber change
Histopathology of MI: 4-12h from infarction.
- Coagulation necrosis
- Neutrophil infiltration (6-8h)
- Nuclear pyknosis (at 12h)
Histopathology of MI: when does neutrophil infiltration peak?
48h
Histopathology of MI: 3 days after infarction.
Vessel proliferation
Histopathology of MI: 4 days after infarction.
- Fibroblast proliferation
2. Macrophage infiltration
Histopathology of MI: 9 days after infarction.
Collagen deposition
Histopathology of MI: 2-4 weeks post-infarction.
Granulation tissue formation/peak
Histopathology of MI: when would you expect to see mature scar?
Over 6 weeks post-infarct
Infarctions can be described pathologically by the extent of (X) they produce within the myocardial wall. (Y) infarcts span its entire thickness.
X = necrosis Y = transmural
The (X) myocardial layers are particularly susceptible to ischemia because this zone is subjected to the highest (Y) and has few (Z) that supply it.
X = subendocardium (innermost) Y = pressure from the ventricular chamber Z = collateral connections