Health and medicine: Left ventricular pressure vs. time

Ever wonder exactly how the left ventricle's pressure changes over time? Find out in this color-coded video! Rishi is a pediatric infectious disease physician and works at Khan Academy.

Health and medicine

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Pressure Volume Loops

The pressure volume loop is one of the classic figures that helps us to conceptualize and understand the mechanics of the left ventricle of the heart. In addition to a filling up with blood and squeezing out blood there is a (very short) period of time when the heart muscle is contracting and relaxing with no volume change! As the left ventricle moves around the PV loop with each lub dub you get a sense for the amazing amount of work it does as pressures and volumes go up and down, all day, every day. This is a fascinating area where physics and biology meet to produce something miraculous.

Topic: Science

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