The pericardium is not essential for life; no adverse consequences follow congenital absence or surgical removal of the pericardium. However, the pericardium serves many important (although subtle) functions

Table. Functions of the Pericardium

Mechanical

Effects on chambers

Limits short-term cardiac distention

Facilitates cardiac chamber coupling and interaction

Maintains pressure-volume relation of the cardiac chambers and output from them

Maintains geometry of left ventricle

Effects on whole heart

Lubricates, minimizes friction

Equalizes gravitation and inertial hydrostatic forces

Mechanical barrier to infection

Immunologic

Vasomotor

Fibrinolytic

Modulation of myocyte structure and function and gene expression

Vehicle for drug delivery and gene therapy

It limits distension of the cardiac chambers and facilitates interaction and coupling of the ventricles and atria.1 Thus, changes in pressure and volume on one side of the heart can influence pressure and volume on the other side. Limitation of cardiac filling volumes by the pericardium may also limit cardiac output and oxygen delivery during exercise.1 The pericardium also influences quantitative and qualitative aspects of ventricular filling; the thin-walled right ventricle (RV) and atrium are more subject to the influence of the pericardium than is the more resistant, thick-walled left ventricle (LV).