Incidence of pericardial effusion in patients presenting to the emergency department with unexplained dyspnea

Objective: To evaluate the frequency of pericardial effusion in patients presenting to the emergency department (ED) with unexplained, new-onset dyspnea. Methods: This prospective observational study took place at an urban community hospital ED with a residency program and an annual census of 65,000 visits. Patients presenting between May 1999 and January 2000 with new-onset dyspnea were eligible if they lacked any pulmonary, infectious, hematological, traumatic, psychiatric, cardiovascular, or neuromuscular explanation for their dyspnea after ED evaluation. Patients received a focused echocardiogram by certified emergency physicians. Data were recorded on standardized data sheets and studies were taped for review. Effusions were categorized as small when the fluid stripe measured less than 10 mm. Moderate-sized effusions measured 10 to 15 mm. Large effusions measured more than 15 mm. Results: One hundred three patients were enrolled. Median age was 56 years (IQR 44, 95% CI = 32 to 67). Fourteen patients (13.6%, 95% CI = 8% to 23%) had effusions. Four had large effusions that explained their dyspnea and were admitted to cardiology; two of these effusions were hemorrhagic, and two were viral in origin. Seven patients with small effusions were treated conservatively at home. Three patients had moderate-sized effusions; all were admitted but treated conservatively. Conclusions: While limited by small numbers, these preliminary data suggest that patients with unexplained dyspnea should be checked for pericardial effusion when bedside ED ultrasound is available.