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Updated: Jun 17, 2026
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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
Drink, drugs, and the QT interval.
Robin A P Weir1, Colin J Petrie, Charles Angus Murphy
1Cardiology Department, Western Infirmary, Glasgow, Scotland, United Kingdom. robinweir75@hotmail.com
Clinical Cardiology
|January 1, 2010
Summary
High drug doses can prolong the corrected QT (QTc) interval, mimicking heart problems. This case highlights how unusual ECGs from drug effects can lead to misdiagnosis and incorrect treatment in syncopal patients.
Area of Science:
- Clinical Cardiology
- Pharmacology
- Electrocardiography
Background:
- Drug-induced prolongation of the corrected QT (QTc) interval is a known phenomenon.
- Multiple repolarization-modulating drugs, especially at high doses, can cause extreme QTc abnormalities.
Observation:
- A syncopal patient presented with an unusual electrocardiogram (ECG).
- The ECG abnormalities were misinterpreted as signs of myocardial ischemia.
Findings:
- The unusual ECG findings were caused by the combined effects of multiple drugs affecting repolarization.
- Misinterpretation of the ECG led to inappropriate management of the patient's syncope.
Implications:
- Clinicians must be aware of drug-induced ECG changes that can mimic acute cardiac events.
- Accurate interpretation of ECGs in patients with polypharmacy is crucial for appropriate syncope management.
- Avoiding misdiagnosis of myocardial ischemia due to drug effects can prevent unnecessary and potentially harmful treatments.
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