Gut microbiota and cardiac arrhythmogenesis: Unveiling the gut-heart axis.

BACKGROUND: Cardiac arrhythmias, a leading cause of morbidity and mortality, have traditionally been linked to structural heart disease and genetic factors. However, growing evidence indicates that the gut microbiota, via its interactions with the cardiovascular system, may also contribute to arrhythmogenesis. The gut-heart axis, involving microbial metabolites, inflammatory signaling, and neural modulation, has emerged as a key regulator of cardiac electrophysiology.

METHODS: This review summarizes recent preclinical and clinical studies investigating the role of gut microbiota in the pathophysiology of cardiac arrhythmias. We examine mechanisms through which microbial products like short-chain fatty acids (SCFAs), trimethylamine N-oxide (TMAO), and bile acids influence arrhythmic risk, with a focus on their effects on ion channels, inflammation, and autonomic regulation.

RESULTS: Evidence from both animal models and human studies indicates that dysbiosis, or imbalance in the gut microbiome, is associated with an increased risk of arrhythmias, including atrial fibrillation and ventricular tachycardia. Microbial metabolites have been shown to influence cardiac electrophysiology through direct and indirect mechanisms, including immune modulation and autonomic nervous system regulation. Furthermore, microbiome-based interventions, such as dietary changes, probiotics, and fecal microbiota transplantation, show promise in reducing arrhythmic burden.

CONCLUSION: The gut microbiota's metabolic, inflammatory, and neural connections with the cardiovascular system increasingly suggest its role in arrhythmia risk. Targeting this gut-heart axis could lead to personalized arrhythmia prevention and treatment strategies.