Pre-Excited Atrial Fibrillation Degenerating Into Ventricular Fibrillation Captured by an Automated External Defibrillator.

An automated external defibrillator (AED) captured the real-time transition from pre-excited atrial fibrillation to ventricular fibrillation in a previously undiagnosed patient with WPW syndrome. This case highlights the malignant potential of rapidly conducting accessory pathways.