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WPW Risk Stratification — EECC MCQ

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HardArrhythmia & ElectrophysiologyWPW Risk StratificationEECC

A 50-year-old man with Wolff-Parkinson-White syndrome has an accessory pathway effective refractory period (ERP) measured at 220 ms during electrophysiology study. What does this indicate about his risk?

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Correct answer: D — A short accessory pathway ERP (≤250 ms) indicates a high-risk pathway capable of rapid conduction during AF, conferring an increased risk of sudden cardiac death

The effective refractory period (ERP) of the accessory pathway is the key determinant of risk in WPW syndrome. A short ERP (≤250 ms) allows rapid antegrade conduction of atrial impulses during AF, producing very fast ventricular rates that can degenerate into VF. The shortest pre-excited RR interval during AF <250 ms is a surrogate marker for high-risk pathways. The ESC 2019 SVT Guidelines and 2024 AF Guidelines recommend catheter ablation for all symptomatic WPW patients (Class I) and should be considered in asymptomatic patients with high-risk features on EP study (short ERP, shortest pre-excited RR <250 ms) or high-risk occupations (Class IIa). Ablation success rates for accessory pathways are >95%.

Reference: ESC (2019): Guidelines on SVT; ESC (2024): AF Guidelines