Serious events were reported in Wolff-Parkinson-White syndrome (WPW). Male sex, young age, sport, septal accessory pathway (AP), short AP refractory period, atrial fibrillation (AF) were reported as risk factors of sudden death (SD). The purpose of the study was to look for the predictors of adverse events in WPW.

Adverse event occurred in 54 of 602 patients with a WPW (9%) (group I). Other patients (group II) had syncope (61), tachycardias (285) or were asymptomatic (205).

Clinical and electrophysiological data were collected. WPW was considered at risk of SD when AF had shortest RR interval<250 ms in control state (CS),<200 ms with isoproterenol.

In group I, event was resuscitated SD (5), syncopal AF requiring urgent treatment. Facilitating factors were heart disease (4), sport (4), stress (2), calcium inhibitors (3), post operative period (2), hyperthyroidism (1). Age was higher in group I (39±18) than II (34±16)**. Sex male was as frequent in groups I and II (65%, 59%). AP left lateral location was more frequent in group I (70%) than II (37%)***, posteroseptal location less frequent in group I than II (20% vs 48%)***. Re-entrant tachycardia was more frequent in group I (30%) than in asymptomatic patients (12.5%)**, but less frequent than in group II patients with tachycardia (80%)***. AF was more frequent in group I (98%) than in asymptomatic patients (23%) or with tachycardia (16 %)***. Maximal rate conducted by AP was higher in group I than II in CS (264±43 b/min vs 186±58) or after isoproterenol (324±26 vs 238±66)**. Malignant form was more frequent in group I (92.5%) than II (10%)***.

risk factors of adverse event as the first manifestation of WPW have changed during the last years. Sport activity was rare but factors as drugs, post surgery were noted. Posteroseptal location was rare and left lateral location was the most frequent location. Age was relatively high and the women had risks similar to those of men.