Single-Photon Emission Computed Tomography in the Diagnosis of Early Postoperative Cognitive Dysfunction After Combined Carotid Endarterectomy and Coronary Artery Bypass Grafting

Abstract

Objective: to study the contribution of regional cerebral blood flow (rCBF) indicators to the diagnosis of early postoperative cognitive dysfunction (POCD) in patients with multifocal atherosclerosis (MFA) with heart and brain revascularization.Material and methods. The study involved 45 patients with MFA of coronary and precerebral arteries. We analyzed patients’ cognitive indicators and conducted brain scintigraphy before and after revascularization. The criteria for inclusion in the study were: scheduled combined revascularization of coronary and precerebral arteries; signed informed consent to participate in the study. Criteria for exclusion were: refusal to participate in the study, diseases that would prevent examination. The study of cognitive functions was performed using flow was assessed by single-photon emission computed tomography using lipophilic radiopharmaceutical 99mTc-HMPAO “Ceretec”.Results. The frequency of early POCD in the isolated coronary artery bypass grafting (CABG) group was 73.3%, in the combined carotid endarterectomy (СEA) and CABG group it was 72.5% (p ˃ 0.05). The rCBF index in the isolated CABG group compared with the combined СEA and CABG group was higher in the right and left temporal lobes (p = 0.01 and p = 0.04), in the right frontal lobe (p = 0.03), right parietal lobe (p = 0.005), and in the right and left occipital lobes (p = 0.03 and p = 0.03). In the postoperative period, in the isolated CABG group, right parietal lobe perfusion (p = 0.01), and right and left occipital lobe perfusion (p = 0.01 and p = 0.01) decreased compared to the baseline values. In the combined СEA and CABG group, in the early postoperative period, cerebral perfusion did not change significantly. Right parietal lobe perfusion was higher in the isolated CABG group compared with the combined CABG and СEA group (p = 0.04). The greatest contribution to the development of early POCD in patients after isolated CABG was made by the left temporal lobe perfusion (p = 0.025), in patients after combined CABG and СEA – by the right parietal lobe perfusion (p = 0.04) in the early postoperative period.Conclusion. Assessment of cerebral perfusion in patients before and after surgery can be used to identify areas affected during surgery, as a method for monitoring the safety of procedure, and as an assessment of the preventive methods against POCD.