The Probability of Incomplete or Hypoplastic Circle of Willis

Abstract

We congratulate Rüffer and colleagues [1Rüffer A. Tischer P. Münch F. et al.Comparable cerebral blood flow in both hemispheres during regional cerebral perfusion in infant aortic arch surgery.Ann Thorac Surg. 2017; 103: 178-185Scopus (20) Google Scholar] for their study. We want to share our opinion about this paper. Rüffer and colleagues performed regional cerebral perfusion through the innominate artery and compared the rate of blood flow in the two hemispheres of patients who underwent aortic arch surgical procedures [1Rüffer A. Tischer P. Münch F. et al.Comparable cerebral blood flow in both hemispheres during regional cerebral perfusion in infant aortic arch surgery.Ann Thorac Surg. 2017; 103: 178-185Scopus (20) Google Scholar]. Figure 4 in their paper reveals that the blood flow rate was higher in the right internal carotid artery than in the left internal carotid artery during total body perfusion. An incomplete or hypoplastic circle of Willis is a common phenomenon and is a recognized anatomic variant. It may lower the transfer of blood from the right hemisphere to the left hemisphere through the anterior or posterior communicating artery. Thus, we claim that this anatomic variant may be one of the reasons for the significantly low blood flow rate that was shown in Figure 4. Moreover, oxygen saturation was found to be significantly lower during regional cerebral perfusion than during total body perfusion in the right hemisphere. As a result, we think that preoperative examination of the circle of Willis should be performed because operative results can be affected if the circle is incomplete or hypoplastic. Comparable Cerebral Blood Flow in Both Hemispheres During Regional Cerebral Perfusion in Infant Aortic Arch SurgeryThe Annals of Thoracic SurgeryVol. 103Issue 1PreviewCerebral protection during aortic arch repair can be provided by regional cerebral perfusion (RCP) through the innominate artery. This study addresses the question of an adequate bilateral blood flow in both hemispheres during RCP. Full-Text PDF ReplyThe Annals of Thoracic SurgeryVol. 107Issue 5PreviewWe agree with Cakir and colleagues [1] that an incomplete or hypoplastic circle of Willis can increase the risk of inadequate left cerebral perfusion during aortic arch repair using regional cerebral perfusion on cardiopulmonary bypass. In addition, even during extended resection and repair of aortic coarctation by lateral thoracotomy, a communicating circle of Willis is mandatory for adequate bilateral cerebral perfusion, when left-sided supraaortal vessels are clamped. Full-Text PDF