Anti-NMDA receptor encephalitis associated with severe sinoatrial node dysfunction: three case reports and a review of the literature.

OBJECTIVES

To summarize the clinical features and management of severe sinoatrial node dysfunction in anti-N-methyl-D-aspartate (NMDA) receptor encephalitis, and to raise awareness of this rare but life-threatening complication.

METHODS

We retrospectively analyzed three patients with anti-NMDA receptor encephalitis who developed sinus arrest and reviewed similar published cases. PubMed, Web of Science Core Collection, and Google Scholar were searched for reports published between January 2005 and January 2025 using the terms "anti-N-methyl-D-aspartate receptor encephalitis," "anti-NMDAR encephalitis," "cardiac arrest," "sinus node dysfunction," "sinus arrest," "sinus pause," and "asystole." Only cases with confirmed anti-NMDAR encephalitis, documented cardiac rhythm abnormalities, and sufficient clinical data were included.

RESULTS

In our three patients, sinus arrest lasted 5.71, 9.23, and 6.20 s, occurring on hospital days 17, 6, and 15, respectively. One patient underwent teratoma resection and received a temporary pacemaker. All three patients regained normal sinus rhythm after immunotherapy and achieved favorable clinical outcomes. The literature review identified 25 additional cases. In a pooled cohort of 28 patients, most were young women; sinus arrest often coincided with seizures and generally manifested during the acute phase. Overall, 76.92% of patients attained complete or partial recovery following immunotherapy, with tumor resection and temporary pacing used as clinically indicated.

CONCLUSION

Sinus arrest represents a reversible yet critical complication of anti-NMDA receptor encephalitis. Sinus node dysfunction resolved within weeks following immunotherapy and, when applicable, tumor resection. Early recognition and combined management are essential.