A nonspecific hypersensitivity reaction caused by TRAUMA to the PERICARDIUM, often following PERICARDIOTOMY. It is characterized by PERICARDIAL EFFUSION; high titers of anti-heart antibodies; low-grade FEVER; LETHARGY; loss of APPETITE; or ABDOMINAL PAIN. The disease is Postpericardiotomy Syndrome (EFO_1001404). Also known as: post-pericardiotomy syndrome.