Despite correct positioning pulmonary artery catheters may be displaced accidentally. Repositioning may prove to be difficult, especially when high pulmonary artery pressures are present. After failure of usual placement methods, transoesophageal echocardiography was used to guide repositioning of a displaced Swan-Ganz catheter in the early postoperative course after cardiac surgery in a child. This technique proved to be useful in visualizing intracardiac catheter orientation and facilitating pulmonary artery catheter placement at bedside, avoiding transportation of a haemodynamically unstable patient.