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Levofloxacin-induced torsades de pointes
Parag D Patel1, Hamid Afshar, Yochai Birnbaum
1Department of Medicine, Section of Cardiology, Baylor College of Medicine, Houston, Texas 77030, USA.
Texas Heart Institute Journal
|April 20, 2010
Summary
A 91-year-old woman experienced drug-induced torsades de pointes, mimicking myocardial infarction. This case highlights challenges in distinguishing nonischemic ST elevation from ST-segment elevation myocardial infarction.
Area of Science:
- Cardiology
- Pharmacology
Background:
- Distinguishing ST-segment elevation myocardial infarction (STEMI) from non-STEMI ST elevation is critical for appropriate treatment.
- Drug-induced arrhythmias can present with electrocardiographic findings mimicking acute coronary syndromes.
Observation:
- A 91-year-old woman presented with flu-like symptoms and polymorphic ventricular tachycardia.
- Electrocardiogram showed Q waves, ST-segment elevation, and prolonged QT interval, initially suggesting STEMI.
- Coronary angiography revealed minimal abnormalities.
Findings:
- The patient was taking levofloxacin, a known QT-prolonging antibiotic.
- The ventricular tachycardia was diagnosed as drug-induced torsades de pointes, not STEMI.
- Levofloxacin-induced torsades de pointes can mimic ischemic ST elevation.
Implications:
- This case underscores the importance of a thorough medication history in patients with ST elevation.
- Clinicians must consider drug-induced arrhythmias when evaluating ST elevation and ventricular tachycardia.
- Accurate differentiation is essential to avoid unnecessary invasive procedures and ensure correct management.
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