RESUMO
Drug-induced long QT syndrome (LQTS) is defined as prolonged corrected QT interval (QTc ≥460 ms) plus polymorphic ventricular arrhythmia fitting the description of torsades de pointes temporally associated with the administration of a drug or combination of drugs. Amiodarone therapy is a known uncommon cause of acquired QT interval prolongation that should not be underestimated. We present a case of an iatrogenic electrical storm with atrial fibrillation (AF) in which amiodarone was administered to attempt chemical cardioversion, resulting in an unnoticed prolongation of the QT interval, with subsequent repeated polymorphic ventricular tachycardia, managed with isoproterenol. Concomitant drugs and slight electrolyte disturbances potentiated this phenomenon. Given the widespread use of this drug in the emergency department, our case highlights a pertinent matter for all medical emergency practitioners. Additionally, it stresses the significance of potential precipitating factors, such as electrolyte imbalances, which are clinical conditions very frequent in the emergency context, along with the importance of recognizing drug interactions. Finally, this case also emphasizes the vital importance of closely monitoring the patient's receiving amiodarone.