Snapshot A 45-year-old woman presents to the emergency room for a syncopal episode. She currently experiences lightheadedness and palpitations. Her medications include ondansetron and oral contraceptives. An electrocardiogram reveals torsades de pointes. She is given magnesium sulfate. Introduction Clinical definition login to view 1 more bullet Associated conditions login to view 7 more bullets Epidemiology Demographics login to view 2 more bullets Risk factors login to view 2 more bullets Etiology Familial Drugs (ABCDE) login to view 7 more bullets Pathogenesis login to view 3 more bullets Presentation Symptoms login to view 5 more bullets Physical exam login to view 2 more bullets Studies Labs login to view 1 more bullet Electrocardiogram (ECG) login to view 6 more bullets Differential Supraventricular tachycardia login to view 2 more bullets Diagnosis Making the diagnosis login to view 1 more bullet Treatment Conservative login to view 5 more bullets Medical login to view 13 more bullets Operative login to view 4 more bullets Complications Ventricular fibrillation Prognosis Usually preceded by a period of long QT intervals Typically resolves spontaneously but may degenerate into ventricular fibrillation and death