Disease: Clinical Pathophysiology - Vascular
Dysfunction Questions And Answers
Different risk factors (cholesterol, hypertension, diabetes, & tobacco) can each injure the lining
endothelial cells
Injury will elicit a series of cellular interactions (inflammatory response) forming the lesions in
atheroscerosis Explain the "Response to Injury" hypothesis
Oxidized LDL --> endothelial injury --> endothelial receptors --> attracting & adhering to
circulating monocytes --> monocyte migration into subendothelial space --> macrophage -->
ingestion of oxidized LDL --> formation of foam cells
Foam cells become fatty streak
Fibrous collagen connective tissue become fibroproliferative plaque How are fatty streaks
formed?
Soft lipid-rich core
Hard collagen-rich sclerotic tissue What are the 2 components of plaque?
sclerotic component of plaque More voluminous
70% average plaque
Innocuous
,Stabilizes plaque
Prevents disruption
Lipid core of plaque Less voluminous
Dangerous component
Destabilizes plaque
More vulnerable to rupture
gruel exposed to flowing blood What causes thrombus formation?
Injury to the lining of the blood vessel provoking inflammatory response
Early fatty streak formation
Late fibrous plaque formation
Encroachment of the lumen of the vessel impairing the blood flow - chronic stable angina
Plaque rupture - unstable angina and MI Review the process of atherosclerosis formation
Oxygen-carrying capacity
Perfusion pressure
Vascular resistance Whatever are the myocardial determinants of oxygen supply?
hemoglobin content and systemic oxygenation What is Oxygen-carrying capacity
dependent on?
, aortic diastolic pressure Maximal flow is during diastole (relaxation) and perfusion
pressure is approximated by the _________________
atherosclerosis in the epicardial arteries (usually > 70% obstruction)
coronary tone of the epicardial arteries (vasoconstriction)
intrinsic coronary tone of small resistance arteries What is resistance to flow caused by?
wall tension
heart rate
contractility What are the myocardial determinants of oxygen demand?
increase; rise As our heart rate accelerates, the number of contractions and the amount of
ATP consumed per minute ____________ and oxygen requirements ______
decrease As heart rate slows, the amount of ATP consumed and the oxygen demand
________
Positive _______ inotropes directly increase the force of contraction and increases oxygen
demand
Negative _________ inotropic drugs decrease myocardial oxygen demand