Continuous selective bilateral antegrade cerebral perfusion through anomalous innominate artery for repair of root, ascending aortic and arch aneurysm--challenges, vagaries and opportunities of bovine arch variant anatomy and review of literature

Abstract

We describe the repair of a root, ascending aortic and arch aneurysm in a 69-year-old man with a bioprosthetic Shelhigh conduit and cylinder, employing continuous bilateral antegrade cerebral perfusion through an anomalous innominate artery with a bovine arch variant anatomy. The origin of both the innominate artery and the left common carotid artery from a common stem from the arch in this bovine arch variant puts the whole cerebral circulation at risk, on one hand, yet provides an opportunity of continuous bilateral antegrade cerebral perfusion through the right brachial, right axillary, right subclavian or innominate artery, during arch reconstruction under lower body, deep hypothermic circulatory arrest. Safety and adequacy of selective cerebral perfusion through the right axillary artery in patients with normal arch vessel origin depends on an intact circle of Willis. In this bovine arch variant, both cerebral hemispheres can be perfused through the right brachial, right axillary, right subclavian or the innominate artery, independent of the integrity of the circle of Willis, because of the origin of the left common carotid artery from the innominate artery, except for the area supplied by the left vertebral artery. Although this is the first report of innominate artery perfusion for arch reconstruction for aneurysm in a bovine arch variant, we believe the method described has important implications for cerebral protection in light of the generally reported incidence of bovine arch from 13 to 35 percent.