Clinical correlates of PR-segment depression in asymptomatic patients with pericardial effusion.

OBJECTIVES The purpose of this study was to determine the clinical correlates of PR-segment depression among consecutive asymptomatic patients with pericardial effusion (PE) detected by routine echocardiography. BACKGROUND Pericardial effusion is a relatively common finding in clinical practice, but not many studies have evaluated electrocardiographic (ECG) changes associated with the occurrence of PE. METHODS Among 4,061 consecutive patients referred to our echocardiography laboratory, 176 asymptomatic patients had PE correlated with their clinical history and ECG findings. RESULTS PR-segment depression was detected in 40 patients (23%). There were no significant differences in age, gender distribution or heart rate between patients with and without PR-segment depression. Fifteen post-pericardiotomy patients (33%), 19 patients (40%) with malignant disease and 6 patients (46%) with connective tissue disease had PR-segment depression, whereas no patient with heart disease (dilated cardiomyopathy, hypertensive heart disease, old myocardial infarction, valvular heart disease), renal disease or hypothyroidism had PR-segment depression, nor widespread ST-segment elevation. Among 40 patients with PR-segment depression, 8 had ST-segment elevation in the leads of epicardial derivation, 8 had upright T waves, 20 had low to inverted T waves with an isoelectric ST-segment and 4 had ST-T-wave changes due to bundle branch block. CONCLUSIONS PR-segment depression was a relatively common ECG sign associated with clinically silent PE, and it was an ECG indicator of inflammatory pericardial involvement.