Longitudinal Changes in Regional Cerebral Perfusion and Cognition Following Cardiac Surgery.

Abstract

Cardiac surgery has been associated with increased risk of postoperative cognitive decline, as well as dementia risk in the general population. Few studies, however, have examined the impact of coronary revascularization or valve replacement / repair surgery on longitudinal cerebral perfusion changes or their association with cognitive function.We examined longitudinal changes in cerebral perfusion among 54 individuals with cardiac disease; 27 undergoing cardiac surgery and 27 matched controls. Arterial spin labeling (ASL) magnetic resonance perfusion imaging was used to quantify cerebral blood flow within the anterior communicating artery (ACA), middle cerebral artery (MCA), and posterior communicating artery (PCA) vascular territories prior to surgery and postoperatively at 6-weeks and 1-year. Cognitive performance was examined during the same intervals using a battery of tests tapping memory, executive, information processing and upper extremity motor functions. Repeated measures, mixed models were used to examine for perfusion changes and the association between perfusion changes and cognition.Significant postoperative increases in perfusion were observed at 6-weeks within the MCA vascular territory following cardiac surgery (P = .035 for interaction). Perfusion changes were most notable in distal territories of the MCA and PCA at 6-weeks, with no additional changes at 1-year. Postoperative increases in MCA perfusion at 6-weeks were associated with improved psychomotor speed (β = 0.35, P = .016); whereas, no significant differences were found between groups in vascular territory perfusion and cognition at 1-year.Cardiac surgery is associated with significant short-term increases in MCA perfusion with associated improvements in psychomotor speed.