8. Which of the following is the preferred therapy for atrial fibrillation in the setting of Wolff-Parkinson-White syndrome?

A. Procainamide

B. Metoprolol

C. Diltiazem

D. Digoxin

E. Sotalol

The combination of atrial fibrillation and Wolff-Parkinson-White syndrome can be fatal due to rapid conduction of the atrial activity through the accessory pathway resulting in rapid ventricular rates causing ventricular fibrillation. AV nodal blocking agents (metoprolol, diltiazem, digoxin, sotalol) should be avoided in this setting since they paradoxically increase ventricular rates since more atrial activity will pass through the fast conducting accessory pathway and fewer through the AV node itself. Procainamide is the recommended therapy or electrical cardioversion is hemodynamic instability is present.

When atrial fibrillation is seen in a patient with Wolff-Parkinson-White, ablation of the accessory pathway is recommended to prevent future rapid conduction to the ventricles.