Electrical Storm Secondary to Amiodarone-Related Torsades de Pointes Following PCI for Acute Myocardial Infarction: A Case Report

Background: Electrical storm (ES) is a life-threatening complication of acute myocardial infarction (AMI) post-percutaneous coronary intervention (PCI), characterized by recurrent malignant ventricular arrhythmias. Amiodarone, a widely used class Ⅲ antiarrhythmic drug, may induce QT interval prolongation and torsades de pointes (TdP), especially in the presence of electrolyte disturbances and reduced myocardial repolarization reserve. Case presentation: A 78-year-old female with a 20-year history of uncontrolled hypertension was admitted to the emergency department with "chest tightness and retrosternal pain for 5 days, acute exacerbation for 4 hours". Clinical evaluation confirmed acute non-ST-segment elevation myocardial infarction and acute decompensated heart failure. Emergency PCI was performed 6 hours after admission, with successful stenting of the left anterior descending artery (LAD). Amiodarone was administered for new-onset atrial fibrillation, which was followed by progressive QT interval prolongation and hypokalemia. On day 5 of hospitalization, the patient developed TdP-related ES, which was successfully managed with electrical defibrillation, immediate amiodarone withdrawal, electrolyte supplementation, and isoproterenol infusion. Conclusion: For AMI patients receiving amiodarone post-PCI, close monitoring of QT interval (corrected QT, QTc) and electrolyte levels is essential. Timely identification and intervention of modifiable risk factors can effectively improve outcomes of ES caused by amiodarone-related TdP.