QTc-prolonging drugs and the risk of sudden death

Various drugs can be associated with QT prolongation. A prolonged QT interval leads to an increased risk for the development of ventricular tachyarrhythmias, particularly polymorphic ventricular tachycardia (torsades de pointes). Polymorphic arrhythmia may rapidly develop into ventricular fibrillation and cause sudden death. Torsades de pointes is classically associated with early depolarization. This review article discusses the mechanisms of QTc prolongation and triggering factors for proarrhythmia, drugs that prolong QT interval (class III antiarrhythmic agents, antimicrobial agents – fluoroquinolone and macrolide antibiotics, antipsychotic and antidepressant drugs, agents used in general anesthesia, antimycotics, and several other drugs), nonpharmacological and pharmacological risk factors for arrhythmias (due to pharmacokineticpharmacodynamic interactions), the treatment and recommendations to prevent arrhythmia related to QT prolongation.