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

Treatment for Wolff-Parkinson-White 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 Tachyarrhythmias

Hemodynamically Unstable Patients

• Immediate electrical cardioversion is recommended for patients presenting with atrial fibrillation and rapid ventricular response with hemodynamic instability (Class I recommendation) 1
  • Start with 100 J and increase progressively if necessary
  • This is critical due to the high risk of developing ventricular fibrillation

Hemodynamically Stable Patients

• Intravenous antiarrhythmic medications for acute management:
  • Procainamide or ibutilide to restore sinus rhythm (Class I recommendation) 1
  • Alternatives include quinidine, disopyramide, or amiodarone intravenously

Critical Contraindications

• AV nodal blocking agents are strictly contraindicated in WPW with atrial fibrillation (Class III: Harm) 1
  • Avoid: digoxin, non-dihydropyridine calcium channel blockers (verapamil, diltiazem), beta-blockers, and adenosine
  • These medications can accelerate ventricular rate by enhancing conduction through the accessory pathway, potentially precipitating ventricular fibrillation 2, 1

Definitive Treatment

Catheter Ablation

• First-line therapy for symptomatic patients 1
• Particularly indicated for patients with:
  • Pre-excited atrial fibrillation
  • Syncope due to rapid heart rate
  • Accessory pathways with short refractory periods (<250 ms)
  • Multiple accessory pathways
  • Ebstein's anomaly
• Success rates exceed 95% with low complication rates
• Complication rates vary by pathway location:
  • 9.1% for septal pathway locations
  • 2.0% for left-sided pathways

Pharmacological Management

• For patients awaiting ablation or who decline procedure:
  • Class IC antiarrhythmics (flecainide, propafenone) are effective for preventing recurrences 3, 4
  • Propafenone reduces conduction and increases the effective refractory period of the accessory pathway 3

Risk Stratification

High-Risk Features (indicating need for ablation)

• Shortest pre-excited R-R interval <250 ms during atrial fibrillation
• History of symptomatic tachycardia
• Multiple accessory pathways
• Ebstein's anomaly
• History of pre-excited atrial fibrillation

Risk of Sudden Death

• Incidence varies from 0 to 0.6% per year 1
• Highest risk in patients with short anterograde refractory periods (<250 ms) and short R-R intervals during pre-excited atrial fibrillation

Post-Treatment Follow-up

• ECG evaluation at 3 months and annually during the first years after ablation 1
• Patient education about symptoms requiring immediate medical attention
• Approximately 5-10% of patients may experience recurrence of accessory pathway conduction
• Continue to avoid AV nodal blocking agents if there is any suspicion of recurrence
• Monitor for development of atrial fibrillation (risk of 15% over 10 years) even after successful ablation

Clinical Pitfalls to Avoid

• Never use verapamil in WPW syndrome with atrial fibrillation as it may precipitate ventricular tachycardia/fibrillation by allowing conduction through the accessory pathway 2
• Do not use adenosine in patients with known WPW and atrial fibrillation as it can accelerate the ventricular rate 1
• Do not misdiagnose WPW ECG pattern as inferior myocardial infarction due to similar appearance 5
• Recognize that asymptomatic patients may still be at risk for sudden cardiac death, particularly those with high-risk features 1, 6

Catheter ablation has largely replaced long-term pharmacological management as the treatment of choice for WPW syndrome, offering definitive cure with excellent long-term outcomes and significant improvement in quality of life 1, 4.