Operative techniques
Our basic surgical strategies of central repair operations for ATAAD are as follows. As arterial infusion lines for cardiopulmonary bypass, both the axillary and femoral arteries were regularly used. The absence of true-lumen collapse was always confirmed on transesophageal or epi-aortic echography at the start of extracorporeal circulation. In some patients, ascending aorta was clamped and proximal procedure was started during systemic cooling. For brain protection, antegrade selective cerebral perfusion was performed. Under hypothermic circulatory arrest with rectal temperature 25℃, balloon-tipped cannulas with pressure monitor lines were inserted individually to a brachiocephalic artery (BCA), left common carotid artery (LCCA), and left subclavian artery (LSCA) from the true lumen of the aortic arch. Cerebral perfusion was conducted by three separate small roller pumps. Start-up perfusion flow rate was 5ml/kg for BCA, 3.3ml/kg for LCCA, and 1.7ml/kg for LSCA, and was regulated to keep adequate perfusion pressure and regional oxygen saturation of frontal lobe. The extent of aortic replacement was determined on the basis of the entry site.