Pathophysiology

The pericardium is composed of 2 layers: (i) the outer thicker fibrous pericardium and (ii) the inner visceral or serosal pericardium which is made up of a thin layer of mesothelial cells. In a normal physiological state the pericardial sac between these 2 layers contains 15-50mls of fluid. The combined thickness of these 2 layers should measure less than 2mm [1]. Pericarditis is caused by inflammation of the pericardial layers associated with varying amounts of pericardial fluid collection which may result in a significant pericardial effusion.