Pericarditis in acute myocardial infarction.

In a prospective study of 300 consecutive patients who survived the first 24 h of acute myocardial infarction, pericarditis was present in 44 patients (14-7%). The only factors independently associated with pericarditis were transmural myocardial infarction, extent of myocardial damage, atrial fibrillation, and longer duration of fever. Pericarditis did not affect immediate prognosis or incidence of cardiac rupture. These findings and the high incidence of atrial fibrillation suggest that anticoagulant therapy should not be discontinued in patients with pericarditis complicating acute myocardial infarction.