Pericardial effusion defines the presence of an abnormal amount and/or character of fluid in the pericardial space. It can be caused by a variety of local and systemic disorders, or it may be idiopathic. Pericardial effusions can be acute or chronic, and the time course of development has a great impact on the patient's symptoms. Treatment varies, and is directed at both removal of the pericardial fluid and alleviation of the underlying cause, which usually is determined by a combination of fluid analysis and correlation with comorbid illnesses.
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