Statistical Characterization of Brain Functional Connectivity in Patients at Risk of Post Operative Cognitive Decline

Patients undergoing coronary artery bypass grafting (CABG) surgery are at significant risk of post-operative cognitive decline (POCD). This study employs resting state functional magnetic resonance imaging (rs-fMRI) to assess functional connectivity (FC) in patients with critical coronary artery disease scheduled for elective or urgent CABG. Baseline fMRI scans and Follow-Up imaging performed three months post-surgery were analyzed to evaluate subject-specific changes in FC, employing mutual information (MI) to quantify pairwise brain interactions. Surrogate- and bootstrap-based statistical validations approaches were applied to ensure the robustness of the performed investigation. This preliminary study provides new insights into the neural mechanisms underpinning POCD and characterizes subject-specific changes of functional brain connectivity following coronary artery bypass surgery.