The Pericardium is an membrane surrounding the Heart. Its main function is to protect and maintain the Heart. As a protector, it guards against any External pernicious invasion to the inner part of the Heart. Out of the 6 possible Pernicious invasions, the most worrying one for the Pericardium and the Heart is Heat. If they are attacked by pathogenic Heat, it can cause high fever, coma and red tongue.
Physiologically speaking, the Pericardium also assists the Heart to communicate with the rest of body. Together with the Heart, it houses the Mind (Shen -神 ). In case of Pericardium Blood Deficiency, depression and slight anxiety can appear. Blood Heat in Pericardium can also lead to anxiety, insomnia and agitation. Phlegm in the Pericardium can cause mental confusion and mental illness if it is serious.