Four consecutive patients underwent resection and graft replacement of ascending aorta or aortic arch for acute dissection. Retrograde cerebral perfusion (RCP) was used during circulatory arrest. RCP at 15 degrees C was administered through the superior vena cava. Duration of cerebral ischaemia and cardiopulmonary bypass averaged 33 and 156 minutes respectively. Retrograde perfusion flow was regulated from 100 to 800 ml/minute to maintain an internal jugular vein pressure of about 25 cm H2O. All patients survived. Three patients awoke neurologically intact. Minor neurological disturbance was found in 1 patient, he was discharged from hospital at day 11 without any detectable neurological deficit. This technique was attractive because it provided a dry operative field unencumbered by perfusion cannulas or clamps, facilitated construction of a more secure distal anastomosis, and avoided the risk of further injury resulting from the aortic cross clamp. It seems that RCP allows longer circulatory arrest time.