Neural Regulation of Cardiac Arrhythmias: From the Brain-Heart Axis to Emerging Precision Therapies

Historically, cardiac arrhythmias have been interpreted as intrinsic ion channel disorders of the cardiomyocyte. However, the field is currently undergoing a fundamental paradigm shift, recognizing the brain-heart axis as the ultimate arbiter of electrical stability. Despite a wealth of preclinical evidence, the clinical translation of neuromodulatory interventions has reached a critical juncture, with many trials yielding conflicting or disappointing outcomes. This translational gap underscores a critical need to move beyond an oversimplified, efferent-centric view toward an integrated understanding of the neuro-cardiac hierarchy. This review redefines arrhythmogenesis as an emergent property of multi-level network instability, driven by 3 core mechanistic principles: spatial heterogeneity, temporal dynamics, and convergent remodeling. By synthesizing the anatomical architecture of the cardiac autonomic nervous system, integrating the often-overlooked afferent sensory limb and the intrinsic "little brain", we illustrate how neural circuits translate systemic stressors into localized electrophysiological triggers. We examine the bidirectional neuroimmune crosstalk and neuropeptide dynamics that bridge inflammatory signaling with maladaptive remodeling. Furthermore, we explore how circadian rhythms impose temporal windows of vulnerability, transforming stable substrates into arrhythmogenic ones. Finally, we critically evaluate the therapeutic landscape, from established pharmacological blockade to the nascent frontiers of closed-loop bioelectronics and nanotechnology. By bridging molecular mechanisms with a hierarchical appraisal of clinical evidence, this review provides a roadmap for the next generation of precision neuromodulation designed to restore and sustain neuro-cardiac homeostasis.