Risk factors of adverse presentation as the first arrhythmia in Wolff-Parkinson-White syndrome.

Background: The aim of the study was the evaluation of the predictors of adverse presentation as first arrhythmia in Wolff-Parkinson-White syndrome; they usually affect young patients with septal or multiple accessory pathways (AP).

Methods: Our population comprised 645 patients with a preexcitation syndrome. Among them, adverse presentation (sudden death, hemodynamically not tolerated atrial fibrillation [AF]) occurred in 60 (9%) (group I). Their clinical and electrophysiological features were compared to group II patients, which consisted of 75 patients with syncope (IIa), 287 with reentrant tachycardia (RT) (IIb), 211 asymptomatic patients (IIc), and 12 with well-tolerated AF.

Results: Sixteen group I patients had triggering factors. Group I patients were older (40 ± 18.5) than group II (34 ± 16) (P = 0.02). Male gender was as frequent in both groups (63%, 59%). Free wall left AP was more frequent in group I (65%) than in group II (37%) (P < 0.001), septal AP less frequent (27% vs 47%) (P = 0.004), multiple APs exceptional. RT was more frequent in group I (57%) than in group IIc (12%) (P < 0.001), less frequent than in group IIb (90.5%) (P < 0.001). AF was more frequent in group I (85%) than in group IIc (22%), or IIb (19%) (P < 0.001). Maximal rate through AP was higher in group I than in group II (P < 0.001).

Conclusions: Adverse presentation in WPW may affect patients older than 35 years of both sexes, with a single free wall lateral AP. All could have been identified by an electrophysiological study.