**3. Pericardial effusion and cardiac tamponade**

Pericardial effusion is classified according to onset as acute, subacute, and chronic when lasting >3 months. The pericardial effusion, which was caused by inflammation leading to increased production of pericardial fluid, is called exudate pericardial effusion. On the other hand, the accumulation of pericardial fluid caused by decrease reabsorption due to an increase in systemic venous pressure as a result of congestive heart failure or pulmonary hypertension is called transudate pericardial effusion.

As of diagnosis, transthoracic echocardiography is recommended (**Figure 1**), and it can assess the size of the pericardial effusion (mild, < 10 mm; moderate, 10–20 mm; or large, > 20 mm), distribution (circumferential or loculated), and hemodynamic effects.

Pericardial effusion is often associated with known or unknown medical conditions such as infections (viral, bacterial, and tuberculosis), cancer, connective

#### *Inflammatory Heart Diseases*

tissue diseases, trauma, and metabolic causes (e.g., hypothyroidism). In developed countries, over 50% of the etiology is idiopathic, whereas tuberculosis is the leading etiology in developing countries.

It is recommended that the therapy of pericardial effusion is targeted at the etiology. When pericardial effusion is associated with systemic inflammation, aspirin/ NSAIDs/colchicine, and treatment of pericarditis are recommended. For cardiac tamponade, symptomatic moderate to large pericardial effusions not responsive to medical therapy, and suspicion of unknown bacterial or neoplastic etiology, pericardiocentesis or pericardial window is indicated.

The common causes of cardiac tamponade include pericarditis, tuberculosis, iatrogenesis (invasive procedure-related, post-cardiac surgery), trauma, and neoplasm/malignancy. The other causes include autoimmune diseases (systemic lupus erythematosus, rheumatoid arthritis, scleroderma), radiation, post-myocardial infarction, uremia, aortic dissection, bacterial infection, and pneumopericardium.
