Catheter ablation of accessory pathways in patients with Wolff-Parkinson-White syndrome.

PATIENTS

Fifty-two patients with Wolff-Parkinson-White syndrome underwent transcatheter ablation. All patients were symptomatic. Eighteen had documented episodes of atrial fibrillation, 14 of which also had reentrant tachycardias; the remaining 34 had only episodes of reentrant tachycardias. Forty-nine patients had both anterograde and retrograde conduction through the accessory pathway; 3 had retrograde conduction alone; 2 patients had 2 accessory pathways and 1 had 3. All patients were resistant or intolerant to at least 2 antiarrhythmic drugs.

METHODS

All patients were treated with radiofrequency current. Ablation was considered successful if the anterograde and retrograde conduction were completely abolished. Ablation was considered unsuccessful if ablation of only 1 pathway in patients with 2 or more accessory pathways and/or modification of the accessory pathway conduction without interruption was achieved.

RESULTS

Accessory pathway ablation was successfully performed in 46 out of 52 patients (88%). Fifty out of 56 accessory pathways were effectively ablated (89%). Thirty-eight required a single session of ablation and 8 additional patients were successfully ablated during a second session. The number of radiofrequency current applications ranged from 2 to 13 (mean 4.1 +/- 2.5). The mean duration of the sessions was 4.30 +/- 1.50 hours (range 2.30 to 9). The mean radiation exposure for session was 55 +/- 25 minutes (range 20 minutes to 2.30 hours). Complications were observed in 2 out of 52 patients. One patient had a transient II degree type 1 atrioventricular block; another patient with severe arterial hypertension had a mild hemorrhagic stroke with complete neurological remission. FOLLOW-UP. Forty-five out of the 46 patients in whom ablation was successful were asymptomatic for arrhythmias during a mean follow-up of 8 months (range 4 to 16), without antiarrhythmic treatment, and without reappearance of preexcitation. One patient showed reappearance of preexcitation at electrocardiogram one month after the ablation, followed by an episode of reentrant tachycardia; this patient underwent a second successful ablation session.

CONCLUSIONS

Our results show that ablation techniques have high success rates with no serious complications.