What is the management of Wolf Parkinson White (WPW) syndrome?

Management of Wolff-Parkinson-White (WPW) Syndrome

Catheter ablation of the accessory pathway is the first-line treatment for symptomatic patients with WPW syndrome, particularly those with syncope due to rapid heart rate or those with a short bypass tract refractory period. 1, 2

Acute Management of WPW with Atrial Fibrillation

Hemodynamically Unstable Patients

• Immediate electrical cardioversion is indicated for patients with WPW in whom AF occurs with rapid ventricular response and hemodynamic instability 1, 2
• This is a Class I recommendation with Level of Evidence B according to ACC/AHA/ESC guidelines 1

Hemodynamically Stable Patients

• Intravenous procainamide or ibutilide should be administered to restore sinus rhythm in patients with WPW in whom AF occurs without hemodynamic instability 1, 2
• This is particularly important when AF is associated with a wide QRS complex (≥120 ms) on ECG 1

Medications to Avoid in WPW

• NEVER administer AV nodal blocking agents in patients with WPW and pre-excited AF 1, 2, 3
• The following medications are contraindicated (Class III recommendation):
  • Beta-blockers 1, 3
  • Digitalis glycosides 1
  • Diltiazem or verapamil 1
  • Adenosine 3
• These medications can facilitate antegrade conduction along the accessory pathway during AF, resulting in acceleration of the ventricular rate, hypotension, or ventricular fibrillation 1, 2

Definitive Treatment

• Catheter ablation of the accessory pathway has a success rate of >95% with a complication rate (permanent AV block) of <1-2% in experienced centers 2
• Complications of ablation include:
  • Right bundle-branch block (0.9% of cases) 2
  • Left bundle-branch block (0.3% of cases) 2
  • Third-degree atrioventricular block (0.1% of cases) 2
  • Small pericardial effusion (0.2% of cases) 2

Risk Assessment for Sudden Cardiac Death

• Annual risk of sudden cardiac death is 0.15-0.2% in general WPW patients, but higher (2.2%) in symptomatic patients 2
• High-risk features include:
  • History of symptomatic tachycardia 2
  • Short RR intervals (<250 ms) between pre-excited beats during atrial fibrillation 2
  • Multiple accessory pathways 2
  • Posteroseptally located pathways 2
• Approximately 25% of patients with WPW syndrome have accessory pathways with short anterograde refractory periods, increasing the risk of rapid ventricular rates and ventricular fibrillation 3

Long-term Management Options

• Catheter ablation is the preferred therapy for symptomatic WPW patients, avoiding lifelong antiarrhythmic drug therapy 2, 4
• For patients who cannot undergo ablation, antiarrhythmic medications that prolong AP refractory periods (flecainide, propafenone, and amiodarone) may be used to prevent rapid AP anterograde conduction 5
• Post-ablation monitoring is necessary, as ablation of the accessory pathway does not always prevent AF, especially in older patients 2

Special Considerations

• Approximately one-third of patients with WPW syndrome may develop atrial fibrillation, which can degenerate into ventricular fibrillation and sudden cardiac death 2
• The risk of developing AF over 10 years in patients with WPW syndrome is estimated at 15% 3
• WPW syndrome is the second most common cause of paroxysmal supraventricular tachycardia, affecting about 0.1-0.3% of the general population 4

By following these guidelines, clinicians can effectively manage patients with WPW syndrome while avoiding potentially dangerous medications that could precipitate life-threatening arrhythmias.