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Updated: May 11, 2026
08:28
Methods for ECG Evaluation of Indicators of Cardiac Risk, and Susceptibility to Aconitine-induced Arrhythmias in Rats Following Status Epilepticus
Published on: April 5, 2011
Thyroid storm and arrhythmic storm: a potentially fatal combination
Diana Anjo1, José Maia, André Couto Carvalho
1Cardiology Department, Hospital Santo António - Centro Hospitalar do Porto, Porto, Portugal.
The American Journal of Emergency Medicine
|May 28, 2013
Summary
Thyroid storm, a critical condition, can trigger rare ventricular arrhythmias even without heart disease. This case highlights the need for vigilant cardiac monitoring during thyroid storm management.
Area of Science:
- Cardiology
- Endocrinology
- Internal Medicine
Background:
- Thyroid storm is a life-threatening endocrine emergency with high mortality.
- Cardiac arrhythmias in thyrotoxicosis are typically supraventricular.
- Ventricular arrhythmias are uncommon and usually linked to pre-existing cardiac conditions.
Observation:
- A 35-year-old woman with Graves disease presented with thyroid storm.
- She experienced multiple malignant ventricular dysrhythmic episodes.
- Crucially, no underlying cardiac disease was identified.
Findings:
- This case suggests thyroid hormones may directly increase myocardial excitability, causing ventricular arrhythmias.
- Myocarditis lesions might act as an arrhythmogenic substrate, exacerbating arrhythmias.
- The direct impact of thyroid hormones on myocardial excitability is implicated.
Implications:
- This case underscores the critical importance of continuous cardiac monitoring in patients with thyroid storm.
- Early detection and management of cardiac arrhythmias are vital for improving outcomes.
- Further research into the mechanisms of cardiac complications in thyroid storm is warranted.
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