# Case Report: Recurrent sinus arrest induced by repeated vomiting

## TL;DR

A 71-year-old woman with a rare neurological disorder experienced recurrent sinus arrest due to severe vomiting, which was reversed with immunotherapy.

## Contribution

This case report highlights a rare autonomic manifestation of NMOSD as a cause of vomiting-induced sinus arrest.

## Key findings

- Vomiting-induced bradycardia progressed to sinus arrest in a patient with NMOSD.
- Treatment with immunoglobulin and steroids resolved symptoms and restored sinus node function.
- A permanent pacemaker was implanted following successful immunotherapy.

## Abstract

Neuromyelitis optica spectrum disorder (NMOSD) can affect autonomic centers in the dorsal medulla, but presentation with recurrent sinus arrest is extremely rare. We report a 71-year-old woman with 10 days of persistent hiccups and vomiting who developed repeated syncopal episodes. ECG monitoring revealed vomiting-induced bradycardia progressing to sinus arrest, and Holter monitoring showed nocturnal sinus pauses up to 40.6 s. Routine cardiac and neurological evaluations were unremarkable, but serum anti–aquaporin-4 antibodies were markedly elevated, and brain MRI demonstrated a dorsal medullary lesion, confirming NMOSD with area postrema involvement. The patient was treated with intravenous immunoglobulin and high-dose methylprednisolone, resulting in complete resolution of vomiting and normalization of sinus node function. A temporary pacemaker was required acutely, and a permanent pacemaker was implanted before discharge. She remained stable on rituximab without relapse. This case underscores that severe vomiting-triggered sinus arrest may be an autonomic manifestation of NMOSD and is reversible with timely immunotherapy.