Risk assessment of pre-excitation: Atrial fibrillation versus atrial flutter

Abstract

Risk stratification for the potential of sudden cardiac death in young patients with Wolff-Parkinson-White (WPW) syndrome remains a somewhat controversial and imprecise exercise. Although clinical parameters such as unexplained syncope or a family history of WPW may correlate with increased risk, most commonly the risk is estimated based on parameters observed during episodes of clinical tachycardia or variables measured during electrophysiology study (EPS).1,2 While variables such as the antegrade accessory pathway effective refractory period or the shortest paced cycle length with pre-excitation during atrial pacing are commonly used, the shortest pre-excited R-R interval (SPERRI) during atrial fibrillation is a generally considered the measurement that best defines the risk of sudden cardiac death, owing to rapid antegrade conduction resulting in ventricular fibrillation.