Brugada-pattern electrocardiogram in propranolol intoxication.
Stephen L Rennyson1, Laszlo Littmann
1Department of Internal Medicine, Carolinas Medical Center, PO Box 32861, Charlotte, NC 28232, USA.
The American Journal of Emergency Medicine
|February 18, 2010
Summary
Severe propranolol toxicity can induce a Brugada ECG pattern, even in individuals without underlying Brugada syndrome. This highlights drug-induced Brugada abnormalities and the risk of sudden cardiac death.
Area of Science:
- Cardiology
- Pharmacology
- Genetics
Background:
- Brugada syndrome is an inherited cardiac condition associated with ECG abnormalities and sudden cardiac death risk.
- It is often linked to mutations in the SCN5A gene, affecting cardiac sodium channels.
- No structural heart disease is typically observed in affected individuals.
Observation:
- Pharmacologic sodium channel blockade can exacerbate Brugada ECG patterns.
- Drug toxicities, including non-antiarrhythmic agents, can induce Brugada ECG abnormalities.
- High doses of propranolol, a beta-blocker, can block cardiac sodium channels.
Findings:
- This report details a case of severe propranolol toxicity.
- The toxicity induced a Brugada ECG pattern in a healthy individual.
- The individual had no prior clinical or ECG indications of Brugada syndrome.
Implications:
- Drug-induced Brugada ECG patterns are a significant clinical consideration.
- Awareness of this phenomenon is crucial for diagnosing and managing cardiac emergencies.
- This case underscores the potential for certain drug toxicities to mimic inherited cardiac conditions.
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