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Arterial Stiffness

5 videos
Believe it or not, the arteries are elastic and when they recoil they actually push blood along when the heart is relaxing (diastole). This is known as the windkessel effect and is the same basic principle used by some water guns. Unfortunately, with all the work that the circulatory system has to do, our arteries can become rigid with age. When the arteries get stiff like lead pipes, the problem is quite different then when the arteries actually get clogged up, but just as important.

Compliance and elastance

VIDEO 9:57 minutes
Learn about compliance (and elastance) of arteries, veins, and lead pipes! Rishi is a pediatric infectious disease physician and works at Khan Academy.

Bernoulli's equation of total energy

VIDEO 6:58 minutes
Learn how total energy of a fluid helps explain why fluids can move from low pressure to high pressure! Rishi is a pediatric infectious disease physician and works at Khan Academy.

Stored elastic energy in large and middle sized arteries

VIDEO 6:21 minutes
See how arteries behave like sling shots, shooting blood (not rocks) onwards! Rishi is a pediatric infectious disease physician and works at Khan Academy.

Compliance - decreased blood pressure

VIDEO 9:55 minutes
Find out how compliance allows arteries to store elastic energy (and lower pressure). Rishi is a pediatric infectious disease physician and works at Khan Academy.

Compliance - increased blood flow

VIDEO 6:54 minutes
Learn how compliant arteries allows for a "Constant Pressure System" like a modern water gun! Rishi is a pediatric infectious disease physician and works at Khan Academy.