Frequency and prognostic significance of pericarditis following acute myocardial infarction treated by primary percutaneous coronary intervention.

Prospective data were collected from 743 consecutive patients with ST-segment elevation acute myocardial infarctions (AMIs) treated with primary percutaneous coronary intervention (mean age 65.3 +/- 11.6 years, 36.7% women). Early post-AMI pericarditis was diagnosed in 31 patients (4.2%; mean age 62.1 +/- 13.4 years, 41.9% women), with an increasing prevalence according to presentation delay (p <0.001): 1.7% for <3 hours, 5.4% for 3 to 6 hours, and 13.6% for >6 hours. Late post-AMI pericarditis (Dressler syndrome) was recorded in only 1 patient (0.1%). On multivariate analysis, patients with presentation times >6 hours (odds ratio 4.4, 95% confidence interval 2.0 to 9.8, p <0.001) and primary percutaneous coronary intervention failure (odds ratio 2.8, 95% confidence interval 1.1 to 7.4, p = 0.032) were at increased risk for developing early post-AMI pericarditis. Although pericarditis is associated with a larger infarct size, in-hospital and 1-year mortality and major adverse cardiac events were similar in patients with and without pericarditis. In conclusion, early primary percutaneous coronary intervention may reduce the occurrence of early post-AMI pericarditis within the first 3 hours of symptom onset. Early post-AMI pericarditis remains a marker of larger infarct size but without independent prognostic significance.