Key Monitoring Considerations in Wolff-Parkinson-White Syndrome
Patients with Wolff-Parkinson-White (WPW) syndrome should be monitored primarily for tachyarrhythmias, particularly atrial fibrillation with rapid ventricular response, which can lead to ventricular fibrillation and sudden cardiac death. 1
Symptoms to Monitor
- Palpitations - The most common symptom, representing episodes of tachyarrhythmias that may require intervention 1
- Syncope or near-syncope - Particularly concerning symptom that may indicate rapid conduction over the accessory pathway and risk of sudden death 1
- Dizziness - May occur during tachyarrhythmias and should prompt evaluation 1
- Chest pain - Can occur during tachyarrhythmia episodes, though less common than other symptoms 1
- Shortness of breath - May indicate hemodynamic compromise during tachyarrhythmias 1
- Fatigue - Especially when driving or performing activities, reported by 77% of patients with SVT 1
- Exercise intolerance - Some patients may have reduced exercise capacity due to anomalous left ventricular depolarization 2
Potential Complications
Life-Threatening Complications
- Sudden cardiac death - Risk ranges from 0.15% to 0.39% over 3-10 years of follow-up 1
- Ventricular fibrillation - Can occur when atrial fibrillation conducts rapidly over the accessory pathway 1
- Pre-excited atrial fibrillation - Particularly dangerous when shortest pre-excited R-R interval is <250 ms during AF 1
Other Complications
- Supraventricular tachycardia - Most commonly atrioventricular reentrant tachycardia (AVRT), accounting for 95% of reentrant tachycardias in WPW patients 1
- Atrial fibrillation - Occurs in WPW patients and can be particularly dangerous 1
- Tachycardia-induced cardiomyopathy - Can develop with frequent or incessant tachyarrhythmias 1
Risk Factors for Sudden Death
- Shortest pre-excited R-R interval <250 ms during AF - Strong predictor of risk 1
- History of symptomatic tachycardia - Increases risk of sudden death 1
- Multiple accessory pathways - Associated with higher risk 1
- Ebstein's anomaly - Congenital heart defect that increases risk when present with WPW 1
- Familial WPW - Though rare, associated with high incidence of sudden death 1
- Young age - Risk of sudden cardiac death appears highest in the first two decades of life 1
Diagnostic Monitoring
- 12-lead ECG - Essential for diagnosis and should be obtained during tachycardia episodes whenever possible 1
- Ambulatory ECG monitoring - Recommended for detection and diagnosis of arrhythmias in symptomatic patients 1
- Exercise testing - Consider for patients with exertional symptoms or to assess risk 1
- Electrophysiological study - Gold standard for risk stratification in both symptomatic and asymptomatic patients with pre-excitation 1
Special Considerations
- Driving safety - 57% of patients with SVT experience episodes while driving, with 24% considering it an obstacle to driving 1
- Asymptomatic WPW - Even asymptomatic patients may be at risk; sudden death can be the first manifestation in about half of cardiac arrest cases in WPW patients 1
- Medication precautions - Patients should be warned to avoid AV nodal blocking agents (digoxin, diltiazem, verapamil) during atrial fibrillation as these can increase conduction over the accessory pathway 1
- Pregnancy - Women with WPW may experience complications during pregnancy and require special monitoring 1
Management Considerations
- Catheter ablation - Should be considered for symptomatic patients, particularly those with syncope or documented AF 1
- Acute management of tachyarrhythmias - Immediate cardioversion for hemodynamically unstable patients with pre-excited AF 1
- Medication management - Procainamide is considered safer than AV nodal blockers for acute management of tachyarrhythmias in WPW 3