Pericardial effusion

The pericardium is a thin membrane covering the heart, consisting of two layers. The visceral pericardium (meaning adjacent to the organ) is the inner layer, closely adhering to the heart, while the parietal pericardium is the outer layer. The space between the parietal and visceral pericardium is called the pericardial cavity. The pericardial cavity normally contains 15-50 ml of serous fluid, which acts as a lubricant. Pericardial effusion occurs when the pericardium itself is diseased or when other conditions affect the pericardium, leading to excessive fluid secretion that accumulates in the pericardial cavity. Early pericardial effusion may not present with obvious symptoms. As the condition progresses, symptoms such as dyspnea may appear, and severe cases can lead to shock.