A 27-year-old woman presented with progressive dyspnoea, orthopnoea, left-sided pleuritic chest pain (improved on upright posture), 20 mm of pulsus paradoxus, distant heart sounds, and impending pericardial tamponade (confirmed on two-dimensional echocardiogram). One litre of bloody fluid was removed by pericardiocentesis.

A two-dimensional Doppler echocardiogram and transoesophageal echocardiogram demonstrated …