The patient was referred urgently for clinical review and an echocardiogram. The echocardiogram confirmed the pleural effusion.

Blood analysis revealed no evidence of acute coronary syndrome or heart failure. Similarly, there were no features of infection or uremia, and malignancy was excluded on computer tomography.

A pericardial drain was inserted, and 1750 mL of fluid accumulated. Samples of the fluid was sent for biochemical, microscopic, and immunohistochemical investigation, all of which were negative.

Repeat echocardiography confirmed trace pericardial effusion with no hemodynamic compromise.

The pericardial effusion was thought secondary to an underlying pericarditis.