what causes effusion of the lung
Causes of pericardial effusion can include: 1  Inflammation of the pericardium following heart surgery or a heart attack. 2  Autoimmune disorders, such as rheumatoid arthritis or lupus.  Spread of cancer (metastasis), particularly lung cancer, breast cancer, melanoma, leukemia, non-Hodgkin's lymphoma or Hodgkin's disease.