According to the Four Levels theory, pathogenic Heat can penetrate four levels of depth in the human body: Wei (卫，the defensive Qi level), Qi (气）, Ying (营，Nutritive Qi) and the deepest level Blood. The deeper Heat penetrates within the levels, the more severe the condition.

As for the pattern of Heat in Pericardium, its the Heat entering the third severe level of Ying. It can also be called Heat at the Upper Burner stage.

At this level, the pathologic Heat starts to harm Yin and dry up the Body Fluids. Therefore, the tongue is dry without coating. The Heat mists the Mind which then lose its residence at the Heart and it cause delirium, mental confusion and incoherent speech. One other key characteristic symptom is the severe night fever.

Despite of the intense Heat invading the body, the hands and feet are cold. It is because the Qi circulation to the limbs are damaged due to the true Heat itself. Therefore, the cold of hands and feet is empty in nature.