Neurocardiology: Brain-Heart Interactions in the Heart.

The heart and brain maintain systemic homeostasis through continuous bidirectional communication mediated by neural regulation, biochemical signaling, and mechanical transduction. Disruption of this communication is increasingly recognized as a contributor to cardiovascular, neurological, cognitive, and psychological disorders. Growing evidence indicates that autonomic imbalance, neuroimmune activation, hemodynamic disturbances, inflammation, altered interoception, and brain network remodeling can mediate cross-organ injury between the heart and brain. These mechanisms underlie a spectrum of heart-brain comorbidities, but their shared pathways, disease-specific manifestations, and integrated management strategies remain insufficiently understood. In this review, we summarize the physiological basis of heart-brain interactions, focusing on neural, biochemical, and mechanical pathways. We then discuss six representative disorders: Takotsubo syndrome, epileptic heart, stroke-heart syndrome, heart failure, cardiac dementia, and psychocardiology. For each condition, we highlight key epidemiological features, pathophysiological mechanisms, and integrated heart-brain management strategies. We also review clinical trials targeting heart-brain interactions, including autonomic modulation, biomarker monitoring, neuroimaging assessment, exercise therapy, psychological intervention, and pharmacological therapy. By integrating basic mechanisms, clinical phenotypes, and translational advances, this review provides a systematic framework for understanding heart-brain comorbidities and advancing precision heart-brain medicine.