RECURRENCE RATE AFTER ACCESSORY PATHWAY ABLATION

Objective-To evaluate characteristics of patients and accessory pathwa ys as well as additional technical factors involved in the reappearanc e of accessory pathway conduction after successful ablation. Design-An alysis of recurrences after radiofrequency ablation. Setting-163 conse cutive patients with 167 accessory pathways. Subjects-97 men and 66 wo men with a mean (SD) age of 36 (14) range (11 to 75) years. Results-Af ter a mean (SD) follow up of 14 (7) range (2 to 27) months, conduction recurred in 13 out of 167 (7.8%) accessory pathways. The initial mani festation of recurrence was circus movement tachycardia in 7 patients and reappearance of delta waves on a 12 lead electrocardiogram in 6 pa tients. The interval to the return of accessory pathway conduction ran ged from 3 hours to 90 days. Age, sex, presence of multiple accessory pathways, criteria to determine the target ablation site, number and d uration of radiofrequency applications, and cumulative energy did not significantly differ between the groups with recurrence and without. R ecurrence was less common with concealed accessory pathways (2/44) tha n with overt accessory pathways (11/110). The difference was not signi ficant. The only variable to influence the recurrences in this study g roup was the location of the accessory pathway. Reappearance of conduc tion through right sided accessory pathways occurred significantly mor e often than through left sided ones (8/40 v 5/114, P = 0.01). Conclus ion-After radiofrequency ablation the recurrence rate of accessory pat hways is low and there are no predictors of the risk of reappearance o f conduction apart from the right sided location of the accessory path way.