CIRCULATORY SYSTEM

The heart is a hollow, muscular organ that maintains blood circulation throughout the body. Learn how the circulatory system - your heart, blood vessels and blood - bring nutrients to the body.
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What determines the rhythm of your heart?

When it comes to the heart, timing is critical. An irregular heartbeat is inefficient and deprives the body of blood. So what sets your ticker's rhythm?

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SYMPTOM CHECKER

DISEASES A-Z

Learn more about what ails you. Here are some common symptoms.

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Common Symptoms: