Cardiovascular part 1

Question 1

Define: arterosclerosis

Answer 1

chronic inflammatory response in the walls of arteries, in large part due to deposition of lipoproteins ( plasma proteins that carry cholesterol and triglycerides
* plaque formation in the arteries

Question 2

When does Atherosclerosis become seriously symptomatic

Answer 2

when interfering with the coronary circulation supplying the heart or cerebral circulation supplying the brain

Question 3

Peripheral Artery occlusive dz

Answer 3

Atheroma in arm, or more often in the leg arteries, and producing decreased blood flow

Question 4

What cellular element are involved in the development of atherosclerosis

Answer 4

endothelial cells, smooth muscles, platelets, leucocytes and chemotactic and inflammatory mediators

Question 5

Atherogenesis

Answer 5

a result of complex and incompletely understood interactions that exist b.n cellular elements and other biological processes of atherosclerosis

Question 6

what are the biological processes that contribute to atherogenesis and the clinical manifestation of atherosclerosis

Answer 6

Vasomotor function, thrombogenicity of the blood vessel wall, state of activation of the coagulation cascade, the fibrinolytic system, smooth muscle cell migration and proliferation and adrenergic stimulus

Question 7

Response-to-injury theory of atherosclerosis

Answer 7

endothelial injury is the principle factor initiating a process that results in atherogenesis

Question 8

what is the pathway for the response to injury model

Answer 8

Vascular injury( mechanical, immune complexes, homocysteine) -> trapping of LDL in arterial wall-> oxidation of LDL (oxLDL) -> Adherence/migration monocytes/T-cells into sub endothelium-> Monocytes/macrophages digest lipid “foam cels” -> foam cells, T-cells, and smooth muscle “fatty Streak” ->continued cell influx and smooth muscle proliferation “ fibrous plaque –> fissuring/rupture of the plaque with activation of platelets and thrombogenesis -> occlusive thrombi and ischemic event

Question 9

What are some of the factors which can potentially contribute to endothelial injury

Answer 9

hypertension and cell wall damage from sheer forces of blood flow, elevated levels of oxidized low density lipoprotien (LDL), hyperglycemia, hyperhomocyctinemia, infectious agents, and cellular damage due to a variety of chemical toxins- particularly the byproducts of cigarette smoke

Question 10

Fatty Streak

Answer 10

• Earliest grossly visible pathologic lesion of atherosclerosis
• occur as a result of focal accumulation of serum lipoproteins within the intimate of the vessel wall
• microscopy of fatty streaks reveals lipid laden macrophages, T lymphocytes , and smooth muscle cells in varying proportions
• observed in the aorta and coronary arteries of most individuals by 20 yrs old

Question 11

Fibrous plaque

Answer 11

• progresses fatty streak from lipid accumulation and the migration and proliferation of SM cells
• these SM cells are responsible for the deposition of extracellular connective tissue matrix forming a fibrous cap that overlies a core of lipid-laden foam cells, extracellular lipid, and necrotic cellular

Question 12

Describe lesion formation in atherosclerosis

Answer 12

• do not occur in a random fashion
• hemodynamic factors interact with the activated vascular endothelium
• fluid shear stresses generated by blood flow influence the phenotype of the endothelial cells by modulation of gene expression and regulation of the activity of flow sensitive proteins

Question 13

describe plaques in aretiosclerosis

Answer 13

• characteristically occurs in region of branching and marked curvature at areas of geometric irregularity and where blood undergoes sudden changes in velocity and direction of flow
• increased shear stress and turbulence promoted atherogenesis at important sites within the coronary arteries, the major branches of the thoracic and abdominal aorta, and the large vessels of the lower extremities

Question 14

What is the product of growth of fibrous plaues

Answer 14

Growth of the fibrous plaque results in vascular remodeling, progressive luminal narrowing, blood-flow abnormalities, and compromised oxygen supply to the target organ.
Ischemia is an imbalance between the supply of blood (oxygen) to a tissue and that tissue’s demand for oxygen.

Question 15

what happens with ischemia in Artherosclerosis

Answer 15

comprises not only diminished oxygen delivery bit also reduction of the availability of nutrient substances as well as the inadequate removal of metabolites

Question 16

Coronary Artery Disease (CAD)

Answer 16

the term used to describe a reduction in blood for to cardiac muscle

Question 17

Ischemia heart Disease (IHD)

Answer 17

refers to an inadequate supply to demand ratio by heart muscle