Management of Wolff-Parkinson-White Syndrome in Pregnancy
Catheter ablation of the accessory pathway is the recommended first-line treatment for symptomatic women with WPW syndrome who are planning pregnancy, as it provides definitive treatment with success rates exceeding 95% and eliminates risks during pregnancy. 1
Pathophysiology and Risks During Pregnancy
WPW syndrome is characterized by an accessory pathway that bypasses the AV node, predisposing patients to tachyarrhythmias. During pregnancy, several physiological changes can increase arrhythmia risk:
- Increased blood volume and cardiac output
- Hormonal changes affecting cardiac conduction
- Heightened adrenergic tone
- Emotional stress
These changes may trigger or worsen arrhythmias in pregnant women with WPW syndrome, potentially leading to:
- Supraventricular tachycardias (SVT)
- Pre-excited atrial fibrillation
- Hemodynamic compromise affecting maternal and fetal wellbeing 2, 3
Pre-pregnancy Management
For women with known WPW syndrome planning pregnancy:
- Catheter ablation of the accessory pathway is strongly recommended before conception for symptomatic patients (Class I recommendation) 1
- Risk stratification should be performed to identify high-risk features:
- Short refractory period of accessory pathway (<250 ms)
- Multiple accessory pathways
- History of pre-excited atrial fibrillation
- Associated cardiac anomalies (e.g., Ebstein's anomaly) 1
Management During Pregnancy
Asymptomatic Patients
- Regular cardiac monitoring throughout pregnancy
- No specific treatment required if asymptomatic
- Education about warning symptoms requiring immediate medical attention
Acute Management of Arrhythmias
For hemodynamically unstable patients:
For hemodynamically stable patients with SVT:
- First-line: Vagal maneuvers
- Second-line: Intravenous adenosine for narrow complex tachycardias without pre-excitation 5, 6
For pre-excited atrial fibrillation:
CRITICAL SAFETY WARNING: Never administer AV nodal blocking agents (diltiazem, verapamil, beta-blockers, digoxin) to patients with WPW and suspected pre-excited atrial fibrillation as they can accelerate conduction through the accessory pathway, potentially precipitating ventricular fibrillation (Class III: Harm recommendation) 1
Maintenance Therapy
If antiarrhythmic therapy is required during pregnancy:
- Beta-blockers (except atenolol) are generally considered safe after the first trimester 4
- Sotalol may be considered for refractory cases (Class IIb recommendation) 4
- Amiodarone should be avoided due to fetal thyroid and developmental concerns
Delivery Planning
- Multidisciplinary approach involving cardiology, obstetrics, and anesthesiology
- Continuous cardiac monitoring during labor and delivery
- Have emergency equipment (including defibrillator) immediately available
- Vaginal delivery is preferred in hemodynamically stable patients 4
- Consider early cesarean delivery if ventricular function deteriorates or arrhythmias become difficult to control 4
Post-partum Considerations
- Continue cardiac monitoring for 24-48 hours post-delivery
- Reassess need for long-term management
- Consider definitive treatment with catheter ablation if not performed previously
- Breastfeeding considerations:
- Beta-blockers generally compatible with breastfeeding (metoprolol preferred)
- Women taking D-penicillamine should not breastfeed 4
Special Considerations
WPW with Ebstein's Anomaly
Patients with Ebstein's anomaly commonly have associated WPW syndrome (2-4%) and require more intensive monitoring during pregnancy due to higher risk of arrhythmias and heart failure 4
WPW with Congenital Heart Disease
Patients with other forms of congenital heart disease and WPW require specialized care at centers experienced in managing adult congenital heart disease during pregnancy 4
By following these guidelines, most pregnant women with WPW syndrome can have successful pregnancies with minimal maternal and fetal complications.