Adenosine-induced ventricular fibrillation.

The use of adenosine has been suggested as a diagnostic tool in the evaluation of wide ORS complex tachycardia. However, adenosine shortens the antegrade refractoriness of accessory atrioventricular connections and may cause acceleration of the ventricular rate during atrial fibrillation. We observed ventricular fibrillation in 2 patients who presented to the emergency department with pre-excited atrial fibrillation and were given 12 mg of adenosine.