The heart is like the boss of your body. It helps manage what all the other parts do. In China, people have a saying that the heart is "the boss of the five main organs and the six other parts." The pericardium is like a shield around the heart. So, if any bad energy tries to mess with your heart, it has to get through the pericardium first.
When the pericardium is in trouble, you might get a high fever or even become confused and really sleepy. These are signs that the pericardium is not doing well.
The heart also takes care of your feelings and thoughts. That's why people in China say, "The heart is the grand boss of the five main organs and six other parts and is the home of the spirit." If your heart is not well, you might have trouble sleeping, dream a lot, forget things, or even feel mixed-up.
Your heart also helps your blood move through special tubes called blood vessels. Your face can show how well your heart is doing. If your heart is good, your face will look bright and you'll feel happy. If your heart is low on blood, your face may look pale and you might feel down.
Your tongue is connected to your heart, too. When your heart is balanced, your tongue can taste all sorts of flavors. If your heart has issues, your tongue will show signs. For example, a pale tongue might mean your heart needs more blood. If your tongue has sores, it might mean there's something wrong with how your blood is flowing. When your tongue feels stiff, it could mean there's a blockage.
In China, people often talk about two ideas: "the heart has its room in the tongue," and "the tongue is like a young plant of the heart."