A narrative review of stellate ganglion block in management of post-operative atrial fibrillation with focus on immunomodulatory mechanisms

Stellate ganglion blockade (SGB) is an uncommon but increasingly relevant therapy used to modulate the autonomic nervous system and reduce the risk of atrial fibrillation (AF). This narrative review focuses specifically on the potential therapeutic role of SGB in new-onset perioperative atrial fibrillation (POAF), a complication associated with adverse long-term outcomes that may diminish the overall benefits of surgery. SGB may reduce AF through several inflammation-mediated mechanisms, including attenuation of direct sympathetic activation and modulation of perioperative inflammatory responses. Because the clinical effects of SGB may persist beyond the expected duration of local anesthetic nerve blockade, we emphasize immunomodulation as a potential mechanism sustaining its beneficial effects and influencing longer-term outcomes. In this review, we examine the immunological effects of SGB in the context of postoperative AF, with particular emphasis on human studies most relevant to clinical practice. Available evidence suggests that, beyond nonspecific inflammation, several less commonly studied cellular components, including mast cells and T cells, may contribute to the initiation and persistence of POAF. These findings support the hypothesis that SGB may reduce POAF by limiting stellate ganglionitis driven by perioperative localized leukocyte activation. Future studies should define the extent, timing, and frequency of this inflammatory process and determine whether specific inflammatory or autonomic phenotypes can identify patients most likely to benefit from SGB.