Health and medicine: Arterial elastance (Ea) and afterload

First, learn the difference between arterial elastance (Ea) and afterload. Then, understand how Ea is affected by changes in afterload, and in turn, how the PV loop can shift. Rishi is a pediatric infectious disease physician and works at Khan Academy.

Health and medicine

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Changing the PV Loop

Once you’ve learned about the PV loop, a natural question arises - Does it ever change shape? It turns out that there are precisely three things that can change the shape of the loop: 1. Preload, 2. Afterload, and 3. Contractility. That’s it! The tricky part comes when you try to change one and you realize that the body begins to change the other two as well as a natural consequence. In order to simplify, you’ll find that PV loops are sometimes even described as PV boxes. You’ll get to learn about PV loops, PV boxes, and even play around with them yourself in this tutorial!

Topic: Science

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