Proarrhythmic potential of antimicrobial agents
1First Department of Internal Medicine, Semmelweis Hospital, Csabai kapu 9-11, Miskolc 3529, Hungary. sjozs74@hotmail.com
Infection
|May 6, 2008
Summary
Certain antimicrobials can prolong the QT interval, increasing the risk of dangerous heart rhythms like Torsades de Pointes (TdP). Physicians should avoid these drugs in patients with risk factors for TdP.
Area of Science:
- Pharmacology
- Cardiology
- Electrophysiology
Background:
- Drug-induced QT interval prolongation is a significant concern, linked to Torsades de Pointes (TdP) and sudden cardiac death.
- Many QT-prolonging drugs, including antimicrobials, exert their effect by blocking the IKr potassium channel in cardiomyocytes.
Observation:
- This review synthesizes current literature on antimicrobial-induced QT prolongation from in vitro, in vivo, and case report studies.
- Data was sourced from the Medline database, focusing on drugs implicated in QT interval lengthening.
Findings:
- Erythromycin, clarithromycin, fluoroquinolones, halofantrine, and pentamidine are frequently associated with QT prolongation.
- Antimicrobial-associated QT prolongation often occurs in patients with multiple risk factors, including drug interactions, female gender, advanced age, structural heart disease, genetic predisposition, and electrolyte abnormalities.
Implications:
- Physicians must exercise caution when prescribing antimicrobials with QT-prolonging potential, especially in at-risk patients.
- Avoiding these agents in patients with multiple risk factors is crucial for preventing TdP and sudden cardiac death.
- Prompt recognition and management of TdP are essential for patient outcomes.
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