Double-dose external cardioversion for refractory unstable atrial fibrillation in the ED.

A 45-year-old man with dilated cardiomyopathy, atrial fibrillation, and hypertension presented to the emergency department with palpitations and shortness of breath for 2 days after running out of his medications. An electrocardiogram disclosed atrial fibrillation with rapid ventricular response. The patient was hemodynamically unstable and failed multiple cardioversion attempts up to 360 J. A second defibrillator was then attached and the patient successfully cardioverted once both defibrillators were set to their maximum levels, thus delivering a total of 720 J. Double-dose external cardioversion with 2 defibrillators is an important alternative method that the emergency physician should be aware of when treating refractory atrial fibrillation in the hemodynamically unstable patient.