The Basics Flashcards
What vessels are effected by atherosclerosis?
Elastic and muscular arteries
What vessels are effected by hypertension?
Small muscular arteries and arterioles
What makes up the intima layer of a vessel?
Endothelial cells
Internal elastic lamina
What makes up the media layer of a vessel?
Smooth muscle cells
Elastin
What makes up the adventitia layer of a vessel?
External elastic lamina
Loose connective tissue including nerve fibers and vasa vasorum
What vessel type is the principle point of physiologic resistance to blood flow?
The arterioles which resist blood flow at an inverse proportional to the fourth power of the diameter of the vessel. In other words minor constriction or dilation of the vessel produced exponential effects on blood pressure.
What body structures does the superior vena cava drain?
Arms
Upper trunk
Head
Neck
What body structures does the inferior vena cava drain?
Abdominal viscera
Lower trunk
Legs
How is cardiac output calculated?
CO= HR X SV CO= the volume of blood ejected from each ventricle during 1 minute
SV= volume of blood ejected with each heart beat
What is preload?
The load that stretches the cardiac muscle before contraction.
What are physiologic increases of preload?
Inspiration
Exercise
What are physiologic decreases of preload?
Exhalation
Decreased left ventricular output
Capillary bed/ venous system blood pooling
What are pathologic effects of preload?
Volume overload
What is myocardial contractility?
The ability of the cardiac muscle, when given a load, to shorten its muscle fibers
What is afterload?
The degree of vascular resistance to ventricular contraction.
What are the two known mechanisms of vascular disease?
Stenosis or obstruction of vessel lumina
Weakening of the vessel walls, leading to dilation or rupture.
What is endothelial activation?
Endothelial cells respond to various stimuli by adjusting their steady state functions and by expressing newly acquired (inducible) properties.
What does C Reactive Protein (CRP) measure?
One of the most sensitive markers for inflammation. CRP increases by a number of inflammatory mediators, particularly IL6.
How can you lower your CRP?
Smoking cessation
Wt Loss
Exercise
Statin therapy
What is endothelial dysfunction?
An alternation in endothelial phenotype often both proinflammatory and prothrombogenic. Structure and function changes the cell and thus attracts attention from the immune system. Leads to low grade chronic inflammation the perpetuates itself.
How are endothelial cells involved in atherosclerosis?
They can be proinflammatroy and prothrobogenic and is partially responsible for the initiation of thrombus formation and atherosclerosis.
How are smooth muscle cells involved with atherosclerosis?
They can have the capacity to proliferate when stimulated and can synthesize collagen, elastin, and proteoglycans which call can elaborate growth factors and cytokines.
How are the tunica media smooth muscle cells similar to fibroblasts?
Smooth muscle cells and their precursors can migrate into the tunica intima and synthesize extracellular matrix in the same way fibroblasts fill in a wound.
