Preexcited Atrial Fibrillation after a Blood Draw

This clinical image report describes a 33-year-old man who developed palpitations and syncope during a routine blood draw. Electrocardiography revealed a wide-complex tachycardia with delta waves and no discernible P waves findings consistent with preexcited atrial fibrillation. The rhythm converted to sinus after intravenous procainamide, revealing a Wolff–Parkinson–White (WPW) pattern characterized by a short PR interval and persistent delta waves. Electrophysiologic evaluation identified a right paraseptal accessory pathway, which was successfully ablated. The patient experienced no recurrence over 18 months. The case highlights the life-threatening potential of preexcited atrial fibrillation in WPW and the efficacy of ablation in managing accessory pathways.

This clinical image report describes a 33-year-old man who developed palpitations and syncope during a routine blood draw. Electrocardiography revealed a wide-complex tachycardia with delta waves and no discernible P waves findings consistent with preexcited atrial fibrillation. The rhythm converted to sinus after intravenous procainamide, revealing a Wolff–Parkinson–White (WPW) pattern characterized by a short PR interval and persistent delta waves. Electrophysiologic evaluation identified a right paraseptal accessory pathway, which was successfully ablated. The patient experienced no recurrence over 18 months. The case highlights the life-threatening potential of preexcited atrial fibrillation in WPW and the efficacy of ablation in managing accessory pathways.