Cross-clamp and Open arch repair:
We routinely cross-clamp the mid ascending aorta once antegrade true lumen perfusion is established through central aortic or axillary artery cannulation. As soon as the cross-clamp is applied, we carefully watch the radial and femoral artery pressure lines for a few seconds. Rarely, significant pressure changes may occur possibly indicating malperfusion, in which case we release the cross clamp and continue with systemic cooling till circulatory arrest.
After the application of the cross-clamp, the proximal aorta is transected just above the level of sinotubular junction and direct ostial cardioplegia is delivered to achieve cardioplegic arrest.
Once systemic cooling is achieved to the desired level, the cross clamp is removed and circulatory arrest is commenced. Retrograde cerebral perfusion is initiated. The ascending aorta and proximal arch are excised. Additional arch segments are excised depending upon the extent of the dissection into the arch vessels 37. Retrograde flow of dark blood through the arch vessels is watched for. An open hemiarch repair is often adequate. If an arch reconstruction beyond hemiarch is required, retrograde cerebral perfusion is switched to bilateral selective antegrade cerebral perfusion. We avoid the use of Bioglue or hemostatic adhesive substances.
Once the arch repair is completed, the arch polyester graft is cannulated and systemic antegrade cardiopulmonary bypass is resumed.
The goal is to maintain antegrade true lumen perfusion throughout the conduct of the operation.