Pericardium
The Pericardium (Xin Bao) is a protective membrane surrounding the Heart that acts as its guardian in TCM. Known as the 'Heart Protector,' it shields the Heart from emotional stress and pathogenic invasion, essentially serving as the emperor's bodyguard while sharing similar functions in governing blood circulation and housing the Mind (Shen).
Five Element Correspondences
Season
Summer
Climate
Heat
Emotion
Joy (shared with Heart)
Color
Red
Taste
Bitter
Sound
Laughing
Direction
South
Sense Organ
Tongue (shared with Heart)
Body Tissue
Blood vessels (shared with Heart)
Body Fluid
Sweat (shared with Heart)
Peak Hours
19-21
Meridian
Pericardium Meridian
Educational content · Consult qualified TCM practitioners for diagnosis and treatment
Overview
The Pericardium, called Xīn Bāo (心包) in Chinese, functions as the Heart's protective outer layer in Traditional Chinese Medicine. Often described as the 'Heart Protector' or 'Master of the Heart,' this organ serves as a crucial buffer between the Heart—considered the Emperor of all organs—and harmful external influences including pathogens, emotional trauma, and Heat.
In TCM theory, the Heart is so vital that it 'cannot receive evil' (邪弗能容). Therefore, when pathogenic factors threaten the Heart, the Pericardium absorbs the attack instead—a function called 'receiving evil on behalf of the Heart' (代心受邪). This protective relationship is especially important in acute febrile diseases where Heat can invade and cause symptoms like delirium and mental confusion.
While the Pericardium shares most physiological functions with the Heart—governing blood, housing the Mind, and expressing joy—it has unique importance in emotional protection and relationship connections. The Pericardium channel also links to the Uterus, giving it special relevance in gynecological conditions related to emotional stress.
Historical Context
The Pericardium's role in TCM evolved significantly over centuries. Early texts like the Huangdi Neijing (Yellow Emperor's Classic) established it as the 'Minister Official' (臣使之官) from which 'joy and happiness emerge.' The Su Wen (Chapter 8) uses the term Tan Zhong (膻中) to describe this protective envelope, emphasizing its role as an intermediary for the Heart's executive functions.
The Ling Shu (Spiritual Pivot, Chapter 71) states that the Heart is the ruler of all organs and residence of the Mind, being 'so tough that no pathogen can enter it'—establishing the doctrinal basis for the Pericardium's protective role. During the Ming and Qing dynasties, the Warm Disease (Wen Bing) school further developed Pericardium pathology, particularly the concept of 'Heat entering the Pericardium' (热入心包) to explain high fever with delirium in infectious diseases.
Historically, some texts considered the Pericardium merely an appendage of the Heart rather than a distinct organ. This explains why classical references often mention only five Zang organs despite having six paired Yin-Yang meridians. However, modern TCM recognizes the Pericardium as functionally independent with its own meridian system.
Physiological Functions
Protecting the Heart
护卫心脏 (Hù Wèi Xīn Zàng)The Pericardium's primary function is to shield the Heart from pathogenic invasion and emotional trauma. Like a bodyguard protecting an emperor, it intercepts harmful influences before they can damage the Heart. This protection extends to both physical pathogens (like Heat in febrile diseases) and emotional stresses that could disturb the Mind housed in the Heart.
Receiving Evil on Behalf of the Heart
代心受邪 (Dài Xīn Shòu Xié)When external pathogenic factors attack the Heart, the Pericardium absorbs the impact first. This is particularly evident in acute infectious diseases with high fever—the resulting delirium and mental confusion are attributed to 'Heat entering the Pericardium' rather than the Heart itself, indicating a less severe prognosis than direct Heart involvement.
Assisting Heart in Governing Blood
助心主血 (Zhù Xīn Zhǔ Xuè)The Pericardium assists the Heart in circulating blood throughout the body. Located in the chest center (Shan Zhong), it helps propel Gathering Qi (Zong Qi) and blood, working closely with both Heart and Lung functions to maintain proper circulation. Pericardium imbalance can manifest as chest oppression, pain, or palpitations.
Housing the Mind (Auxiliary)
辅助藏神 (Fǔ Zhù Cáng Shén)As the Heart's outer envelope, the Pericardium shares in housing the Mind (Shen). When emotional stress or pathogens affect the Pericardium, mental symptoms arise—anxiety, restlessness, insomnia, and in severe cases, mental confusion or delirium. The Pericardium is especially sensitive to emotional disturbances from relationships.
Governing Relationships and Joy
主喜乐 (Zhǔ Xǐ Lè)The Su Wen states that 'joy and happiness emerge' from the Pericardium. It governs our capacity for emotional connection with others, particularly in intimate relationships. The Pericardium influences how we open our hearts to love while maintaining healthy boundaries—a balanced Pericardium supports healthy relationships and appropriate emotional expression.
Connection to Uterus
通于胞宫 (Tōng Yú Bāo Gōng)Through the Bao Mai (Uterus Vessel), the Pericardium connects to the Uterus and influences menstruation. Emotional stress affecting the Pericardium can therefore disrupt menstrual cycles. Blood Deficiency of the Pericardium may cause scanty periods; Pericardium Fire can cause heavy bleeding; Blood Stasis may result in painful periods.
Relationships with Other Organs
Other
The Pericardium serves as the Heart's protective outer envelope and 'minister.' It shares most functions with the Heart—governing blood, housing the Mind, and connecting to joy—while specifically protecting the Heart from pathogenic invasion and emotional trauma. The Pericardium essentially acts as an intermediary, carrying out the Heart's executive functions while shielding it from harm.
Other
The Pericardium and San Jiao (Triple Burner) form a Yin-Yang interior-exterior paired relationship through the Hand Jue Yin and Hand Shao Yang meridians. Classical texts state that 'the San Jiao protects the Internal Organs on the outside, while the Pericardium protects the Heart on the outside'—together they form complementary protective systems for the body's interior.
Other
The Pericardium and Liver connect through the Jue Yin (Terminal Yin) channel system—Hand Jue Yin Pericardium and Foot Jue Yin Liver meridians share this energetic quality. The Pericardium helps the Liver's Ethereal Soul (Hun) in facilitating social connections and emotional expression. Liver Qi Stagnation commonly precedes or accompanies Pericardium Qi Stagnation.
Other
The Pericardium connects with Kidney through the Minister Fire (Ming Men) and the Uterus connection. The Bao Luo (Uterus Channel) links the Pericardium to the Kidneys via the Uterus. In Five Element terms, both Pericardium and Kidney contain aspects of Minister Fire—this relationship affects sexuality, reproduction, and vital warmth.
Generating
Following Five Element theory, Fire (Pericardium) generates Earth (Spleen). When the Pericardium functions optimally, it supports Spleen function through the generating cycle. Enhanced Pericardium energy and proper blood circulation indirectly strengthen the Spleen's transformative and immune functions.
Common Pathological Patterns
Key Manifestations
Key Manifestations
Key Manifestations
Key Manifestations
Key Manifestations
Tongue Manifestations
The Pericardium shares tongue diagnostic areas with the Heart, primarily observed at the tongue tip. In Heat patterns affecting the Pericardium, the tongue appears deep red or crimson, often dry with little or no coating. Phlegm misting the Pericardium produces a swollen tongue body with thick, greasy coating. Blood Deficiency shows a pale, thin tongue that may be slightly dry. Qi Stagnation patterns often reveal a slightly purple or dusky coloration, indicating impaired circulation. The tongue tip specifically may show redness or small red points when Pericardium Fire is present.
Pulse Manifestations
The Pericardium is traditionally assessed at the left Cun (inch) position, the same location as the Heart. In Heat entering the Pericardium, expect a rapid and thready or fine pulse. Phlegm patterns produce a slippery and possibly wiry quality. Pericardium Qi Stagnation may show an overflowing yet empty pulse—strong on the surface but weak with pressure. Blood Deficiency manifests as a choppy (hesitant) and fine pulse, reflecting inadequate blood to fill the vessels. Pericardium Fire generates a rapid and overflowing pulse. The pulse may feel irregular or intermittent when Pericardium pathology affects heart rhythm.
Clinical Relevance
The Pericardium holds particular clinical importance in treating emotional disorders, cardiovascular conditions, and acute febrile diseases with mental symptoms. Its role as the Heart Protector makes it essential when addressing anxiety, depression, and emotional trauma—especially issues arising from relationship difficulties. PC-7 (Daling) is specifically indicated for heartbreak and emotional upset.
In acute conditions, recognizing 'Heat entering the Pericardium' guides treatment of high fever with delirium, requiring formulas that clear Heat and open the orifices. For chronic presentations, Pericardium patterns often manifest as chest oppression, palpitations, and insomnia. The Pericardium's connection to the Uterus makes it relevant in gynecological conditions where emotional stress disrupts menstruation.
Clinically, the Pericardium meridian points—particularly PC-6 (Neiguan)—are among the most frequently used in acupuncture practice for cardiac conditions, nausea, anxiety, and chest disorders. The Pericardium's dual physical and emotional protective functions make it a cornerstone for treating the modern epidemic of stress-related illness.
Classical Sources
Huangdi Neijing Ling Shu
Chapter 71 (Evil Guest)心者……邪弗能容也，容之则伤心，心伤则神去，神去则死矣。故诸邪之在于心者，皆在于心之包络。
The Heart... cannot contain evil. If evil enters, it damages the Heart; if the Heart is damaged, the Spirit departs; if the Spirit departs, death follows. Therefore, all evils that attack the Heart actually reside in its envelope (Pericardium).
Huangdi Neijing Su Wen
Chapter 8 (Discussion of the Secret Orchid Chamber)膻中者，臣使之官，喜乐出焉。
The Tan Zhong (Pericardium) is the Minister Official; joy and happiness emanate from it.
Selected Historical Theories of Chinese Medicine
Wang Xin Hua, 1983三焦护卫诸脏于外，心包络护卫心于外。
The San Jiao protects the Internal Organs on the outside, and the Pericardium protects the Heart on the outside.
Lei Jing Tu Yi (Illustrated Supplement to the Classified Canon)
Channel Section心象尖圆形，如莲蕊……外有赤黄裹脂，一是为心包络。
The Heart resembles an inverted pointed lotus bud... on the outside is reddish-yellow fatty membrane, which is the Pericardium.
Modern References
The Foundations of Chinese Medicine
Comprehensive coverage of Pericardium functions, patterns, and clinical applications in modern TCM practice.
Chinese Acupuncture and Moxibustion
Standard reference for Pericardium meridian pathway, point locations, and clinical indications.
Warm Diseases: A Clinical Guide
Detailed explanation of Heat entering Pericardium patterns within the Four Levels diagnostic framework.
A Manual of Acupuncture
Authoritative reference for Pericardium channel acupuncture points with classical and modern applications.