Insights of stroke in aortic arch surgery: identification of significant risk factors and surgical implication

Abstract

Although the outcomes of aortic arch surgery have improved, stroke remains one of the most devastating complications. Therefore, identification of true risk factors and understanding the pathogenesis of intraoperative stroke are necessary to decrease its occurrence. From January 2002 to December 2010, a total of 251 consecutive patients underwent aortic arch surgery under deep hypothermic circulatory arrest and antegrade selective cerebral perfusion in our hospital. Hemiarch replacement cases were excluded. Of the remaining patients, 190 elective cases that could be reviewed with full perioperative clinical data were analyzed. Strokes were classified into three subtypes according to their distribution on imaging studies: multiple-embolism type, hypoperfusion type, and solitary-embolism type. Operative death occurred in 1.1% of patients (2/190), and aortic arch surgery-related in-hospital death occurred in 5.3%. Among the 188 survivors, intraoperative strokes occurred in 5.9%. Multiple-embolism, hypoperfusion type, and solitary-embolism stroke occurred in 2.7%, 2.1%, and 1.6%, respectively. Multivariate analysis revealed that the risk factor for multiple-embolism stroke was high-grade atheroma in the ascending aorta [P < 0.001, odds ratio (OR) 118.0], and that for hypoperfusion type stroke was prolonged brain ischemia time over 120 min (P = 0.004, OR 31.5). No significant risk factor was found for solitary-embolism stroke. Intraoperative strokes during elective aortic arch surgery under deep hypothermic circulatory arrest and antegrade selective cerebral perfusion are strongly influenced by the presence of a high-grade atheroma in the ascending aorta and prolonged brain ischemia time. The results suggest that these are key issues to reduce stroke in aortic arch surgery.