8/7- Atherosclerosis Flashcards
All of the following are risk factors for atherosclerosis except:
A. Blood pressure > 140/90
B. Elevated LDL cholesterol levels
C. Past history of smoking
D. Age > 45 (male) and 55 (female)
E. Alcohol drinking
All of the following are risk factors for atherosclerosis except:
A. Blood pressure > 140/90
B. Elevated LDL cholesterol levels
C. Past history of smoking
D. Age > 45 (male) and 55 (female)
E. Alcohol drinking
T/F: Atherosclerosis is a disease of “Old Age”?
False!
How early is there clinical evidence of atherosclerosis usually occurring in humans?
A. Infancy and childhood
B. 3rd-4th decade
C. 5th-6th decade
D. Beyond the 6th decade
How early is there clinical evidence of atherosclerosis usually occurring in humans?
A. Infancy and childhood
B. 3rd-4th decade
C. 5th-6th decade
D. Beyond the 6th decade
Note on gender:
*Women typicall 10-15 years older on average with presenting symptoms than men; BUT over the age of 65 they are equal to men, and then around 75, actually have higher burden*
What is NCEP?
National Cholesterol Education Program
What is the normal structure of a blood vessel wall?
- Intima: thin single layer of endothelial cells
- Internal elastic lamina
- Media
- External elastic lamina
- Adventitia
Atherosclerosis is the major cause of ____
Atherosclerosis is the major cause of ischemia
What is seen on EKG with subendocardial ischemia?
ST segment depression
What are some risk factors for atherosclerosis?
- High LDL cholesterol levles (usually > 100 or 130 mg/dL)
- HTN (BP> 140/90 mmHg or anti-hypertensive med)
- DM (considered CHD equivalent)
- Smoking (current or recent only)
- Low HDL cholesterol (under 40 mg/dL)
- Family Hx of “premature” CHD
- Age: Male > 45 or Female > 55
- Infection or inflammation
Atherosclerosis can cause what?
Coronary Heart Disease (CHD)
- > Arrhythmias
- > Heart Failure
- > Sudden cardiac death, Angina (stable or unstable), Myocardial infarction
Important slide!
Note: Coronary Heart Disease (CHD) is the same thing as Coronary Artery Disease (CAD)
Unstable angina and Myocardial infarction are also called ______?
Unstable angina and Myocardial infarction are also called Acute Coronary Syndromes
A pt with stable angina is also described as having _____?
A pt with stable angina is also described as having Stable CAD
Endothelial cell injury results in what?
Atherosclerotic plaque
Describe the modified response to injury in atherosclerosis development
1. Injury to endothelial cells
2. Adherence of monocytes to EC
- Clustering of monocytes/macrophages
- LDL oxidation and accumulation in monocytes -> conversion of monocytes to foam cells
- Lipid rich (monocytes) foam cells
3. Production of GFs and inflammatory cytokines by damaged EC, platelets, and macrophages causes smooth cell proliferation and migration into intima
- Elaboration of ECM -> fibrous cap
4. Platelet aggregation -> thrombus
So: endothelial cells -> monocytes/macrophages/foam cells -> smooth muscle cells -> platelets
What are the final steps in “unstable plaque” development?
- Plaque Rupture or Erosion
- Platelet adhesion, activation & aggregation
- Activation of platelet IIb/IIIa receptors
- Thrombin production by platelets
- Fibrinogen converted to fibrin: mature clot
Hemorrhage from plaque microvessels lead to clot and heart attack or angina
Details of smooth muscle cell proliferation
- GFs responsible? Source?
- Results after treatment?
- GFs derived from platelets (PDGF), EC, and monocytes stimulate smooth muscle cell proliferation and migration into the intima
- SMC proliferation causes restenosis after balloon angioplasty (dilatation), a major limitation of coronary angioplasty