A 29-year-old woman with a tubular thoracic aortic graft prosthesis, placed after repair of a postcoarctation site aneurysm, was reoperated due to fungal infection of the prosthesis. A left thoracotomy was performed and single lung ventilation established through a double lumen tube followed by extracorporeal circulation (ECC), deep hypothermia, and cessation of blood circulation. The venous drainage tube was placed in the right pulmonary artery and arterial return was located in the descending aorta. After replacement of the prosthesis and interruption of ECC, attempts to ventilate the right lung failed. Fiberoptic examination revealed that the carina and tracheal wall completely occluded the opening of the right main bronchus. ECC was interrupted and the left lung was ventilated, but after withdrawal of the tube from the pulmonary artery and repositioning the patient in supine decubitus, oxygenation and right lung ventilation improved. The patient was extubated after 20 hours and discharged home 6 weeks later.