A 62-year-old man is admitted to the hospital with palpitations and chest pain. His prior medical history is important for hypertension, paroxysmal atrial fibrillation, ischemic cardiomyopathy, and coronary artery disease. At the time of admission, both blood pressure and pulse were 135/78 mm Hg. The patient experiences two instances of short unconsciousness while in the hospital. When the events are recorded, the ECG reveals polymorphic QRS complexes, which vary in amplitude and cycle duration. His ECG is unremarkable save from the QT interval lengthening between the episodes. Which of the following medications is most likely responsible for this patient's condition?

Question

Quizplus · Accepted Answer

Eductional Objective: Torsades de pointes (TdP) refers to polymorphic ventricular tachycardia that occurs in the setting of a congenital or acquired prolonged QT interval.  TdP is most commonly precipitated by medications that prolong the QT interval such as certain antiarrhythmics (sotalol, quinidine), antipsychotics (haloperidol), and antibiotics (macrolides, fluoroquinolones).

A 62-Year-Old Man Is Admitted to the Hospital with Palpitations