# Fragile X and Fatal Rhythms: Electroconvulsive Therapy–Induced Ventricular Tachycardia

## TL;DR

A man with Fragile X syndrome experienced dangerous heart rhythms during electroconvulsive therapy, highlighting the need for special precautions.

## Contribution

This case highlights the risk of ECT-induced arrhythmias in FXS and suggests strategies like stellate ganglion block for prevention.

## Key findings

- A patient with FXS developed ventricular tachycardia and cardiac arrest during ECT despite standard antiarrhythmic treatment.
- Pretreatment with left stellate ganglion block and intravenous amiodarone was considered to mitigate arrhythmia risk.
- FXS may increase arrhythmia susceptibility due to elevated sympathetic tone and ion channel abnormalities.

## Abstract

Fragile X syndrome (FXS) is associated with autonomic dysfunction and ion channel abnormalities that increase the risk of arrhythmias. Electroconvulsive therapy (ECT), used to treat catatonia in FXS, can trigger a sympathetic surge, potentially inducing ventricular tachycardia.

A 52-year-old man with FXS and catatonia developed recurrent wide complex tachycardia and cardiac arrest during ECT sessions, despite normal electrolytes, no structural heart disease, and a normal baseline electrocardiogram. The patient had recurrent cardiac arrest despite scheduled oral amiodarone 200 mg 3 times a day and premedication with 30 mg of esmolol. Pretreatment with a left stellate ganglion block and intravenous amiodarone infusion was considered before ECT sessions.

FXS may increase susceptibility to arrhythmia owing to elevated sympathetic tone and channelopathies associated with fragile X mental retardation protein. ECT may amplify this risk, requiring proactive strategies.

Patients with FXS may require individualized pre-ECT risk assessment. Antiarrhythmic and sympathetic modulation strategies, including stellate ganglion block, may be essential for arrhythmia prevention in high-risk cases.