Outcomes following electroanatomic mapping and ablation for the treatment of ectopic atrial tachycardia in the pediatric population.

Ectopic atrial tachycardia (EAT) is often resistant to medical therapy, with radiofrequency ablation (RFA) being a preferred treatment option. Three-dimensional (3-D) electroanatomic mapping was introduced as a tool for improved substrate localization, although there are no published data with this technology in pediatric patients with EAT. The objective of this study was to examine our experience with 3-D mapping and standard mapping in this patient population. We used retrospective chart review of pediatric patients with EAT requiring RFA from 1993 to 2004. We analyzed the method of ablation, acute success and recurrence rates, procedure and fluoroscopy times, and cardiac function. Twenty-five patients underwent 31 RFA procedures. All patients had been followed for >6 months (6 months to 7 years). Standard mapping (Group 1) was used in 11 patients (5F/6M, 1.4-11.8 years) who underwent 13 RFA procedures; 3-D mapping (Group 2, October 2000-2004) was used in 16 patients (8 F/8M, 2.7-17 years) who underwent 18 RFA procedures. Left-sided focus was present in 6/13 in Group 1 and 7/18 in Group 2 (all transeptal, NS). There was a trend toward fewer lesions with 3-D mapping (15 +/- 14, median 9.5 in Group 1; 8 +/- 6, median 6.5 in Group 2, NS). Acute success was more likely for patients in which 3-D mapping was utilized (10/13 Group 1 vs. 18/18 Group 2, p < 0.04). Recurrence or persistence of tachycardia at follow-up (2 weeks to 1 year) was documented in 7/13 cases in Group 1, compared to only 2/18 cases in Group 2 (p = 0.01). Six patients underwent repeat RFA: two patients using standard mapping (one failure, one success) and four patients using 3-D mapping [all acute and long-term (>1 year) success]. Procedure times (232 +/- 84 vs. 268 +/- 72 min, skin-to-skin) and fluoroscopy times (47 +/- 24 vs. 40 +/- 20 min) were similar (NS). Of the 25 pts, 17 (7 in Group 1, 10 in Group 2, NS) presented with cardiomyopathy [Ejection fraction (EF), 38.6 +/- 12.1%]. Successful RFA resulted in improved EF (61.1 +/- 11.6%, p < 0.0001) in the 14 patients in whom pre-RFA and post-RFA echocardiograms were available. Compared to standard techniques, 3-D electroanatomic mapping has resulted in no acute failures, statistically reduced recurrence rates, and improved overall success in the management of EAT.