What is the treatment for Wolff-Parkinson-White (WPW) syndrome?

Treatment of Wolff-Parkinson-White (WPW) Syndrome

Catheter ablation is the first-line therapy for symptomatic WPW patients, with success rates exceeding 95% and low complication rates. 1

Acute Management of WPW with Arrhythmias

Hemodynamically Unstable Patients

• Immediate electrical cardioversion regardless of clinical context 1
• Have defibrillation equipment immediately available and monitor ECG continuously during treatment 1

Hemodynamically Stable Patients with Regular SVT

1. First-line: Vagal maneuvers 1
2. Pharmacotherapy:
   • For pre-excited atrial fibrillation: Intravenous procainamide or ibutilide (Class I recommendation) 1
   • AVOID AV nodal blocking agents (diltiazem, beta-blockers, digoxin, adenosine) in patients with suspected pre-excited atrial fibrillation as they can accelerate conduction through the accessory pathway, potentially precipitating ventricular fibrillation 1
   • AVOID amiodarone in patients with pre-excited AF (Class III: Harm) 1

Definitive Treatment

Catheter Ablation

• Strongly indicated (Class I recommendation) for:

  • Symptomatic patients 1
  • Patients with pre-excited atrial fibrillation 1
  • Patients with syncope due to rapid heart rate 1
  • Accessory pathways with short refractory periods (<250 ms) 1

• Benefits:

  • Success rates >95% 1
  • Significant improvement in quality of life 1
  • Eliminates risk of sudden cardiac death 1, 2
  • Low complication rates 1

• Follow-up after ablation:

  • ECG evaluation at 3 months and annually during first years 1
  • Recurrence rate approximately 5-10% 1
  • Second ablation procedure typically successful if WPW recurs 1

Risk Stratification

High-Risk Features (requiring more aggressive management)

• Short refractory period of accessory pathway (<250 ms) 1
• Multiple accessory pathways 1
• History of pre-excited atrial fibrillation 1
• Associated cardiac anomalies (e.g., Ebstein's anomaly) 1

Risk of Sudden Death

• Varies from 0 to 0.6% per year in patients with WPW syndrome 1
• Higher risk in patients with short anterograde refractory periods and short R-R intervals during pre-excited atrial fibrillation 1

Pharmacological Management (when ablation is not immediately available)

For Long-term Management (if ablation is delayed or refused)

• Class IA or IC antiarrhythmic agents to slow AP conduction 3
• Medications that prolong AP refractory periods (flecainide, propafenone, amiodarone) can prevent rapid AP anterograde conduction 3

Important Cautions

• NEVER administer AV nodal blocking agents (diltiazem, beta-blockers, digoxin, adenosine) to patients with WPW and suspected pre-excited atrial fibrillation 1
• Even after successful ablation, avoid AV nodal blocking agents if there is any suspicion of recurrence 1
• Ablation of the accessory pathway does not always prevent atrial fibrillation, especially in older patients (risk of developing AF over 10 years estimated at 15%) 1

Special Considerations

• Patients with Ebstein's anomaly commonly have associated WPW syndrome (2-4%) and require more intensive monitoring due to higher risk of arrhythmias 1
• WPW may be associated with reduced exercise capacity and LV systolic performance due to anomalous LV depolarization in some cases 2

The treatment of WPW syndrome has evolved significantly, with catheter ablation now being the definitive treatment of choice due to its high success rate and low complication profile, effectively eliminating the risk of sudden cardiac death in these patients.