Brain Network Connectivity in Coronary Heart Disease: A Graph‑Theoretical Review

Coronary heart disease (CHD) has usually been viewed mainly as a cardiac problem, but growing evidence shows it also disrupts how the brain is wired and organized. These changes in brain networks may help explain why many people with CHD experience cognitive decline, mood problems, and autonomic dysfunction. This review synthesizes current knowledge about brain connectivity alterations in CHD and discusses the mechanisms linking heart disease to altered neural networks. The article draws on studies that use graph-theoretical methods to analyze neuroimaging data from multiple modalities: functional MRI (fMRI), diffusion tensor imaging (DTI), electroencephalography (EEG), and magnetoencephalography (MEG). It examines changes in key network properties including small-worldness, modularity, and hub organization. Across the reviewed literature, CHD is frequently associated with a departure from an efficient ”small-world” organization, characterized by reduced clustering coefficients and longer path lengths than in healthy controls findings that suggest weaker local processing and reduced global communication efficiency. Alterations in large-scale networks such as the default-mode network (DMN) and salience network are commonly reported, and these changes have been linked to deficits in executive function and emotional regulation. Overall, the evidence suggests CHD affects the broad-scale topological organization of brain networks rather than just isolated regions. Graph-based metrics may offer useful biomarkers of brain-heart interactions and early indicators of cognitive decline in cardiovascular disease.