Electroanatomical mapping-system guided vs. intracardiac echocardiography-guided slow pathway ablation: a randomized, single-center trial

Abstract Funding Acknowledgements Type of funding sources: None. Introduction Radiofrequency (RF) catheter ablation of the slow pathway (SP) in atrioventricular nodal reentry tachycardia (AVNRT) is highly effective; however, it may require prolonged fluoroscopy and RF time. Procedural outcomes may improve by using electroanatomical mapping systems (EAM), and/or intracardiac echocardiography (ICE). Purpose Our aim was to compare EAM-guided vs. ICE-guided approach for SP ablation in patients with AVNRT. Methods In our single-center study, 65 patients underwent SP ablation due to AVNRT were randomized to ICE-guided or EAM-guided groups. Procedural outcomes (total procedure time, puncture-to-mapping time, mapping-to-last ablation time), fluoroscopy parameters (total fluoroscopy time, radiation dose) and ablation data (number of RF applications, total ablation time) were analyzed. Results ICE guidance reduced puncture-to-mapping time (39.6±7.6 min vs. 32.7±8.2 min; p< 0.001) and total procedure time (68.5 (62.8; 75.3) min vs. 59.5 (56;64) min; p< 0.001). Total fluoroscopy time was shorter (0 (0;0) sec vs. 79 (61; 121.5) sec; p< 0.001), and radiation dose was lower (0 (0;0) mGy vs. 3.1 (2.2; 4.5) mGy; p< 0,001) with the use of EAM. No significant difference was detected regarding mapping-to-last ablation time (6 (2.5;17,0) min vs. 3 (2; 8.3) min; p= 0.13), the number of RF applications (5 (3; 7) vs. 3.5 (3; 5.5); p= 0.30), and total ablation energy (3625 (2513; 5402) J vs. 2676 (1912.5; 5291.5) J; p= 0.10), however total ablation time was shorter in the ICE-guided group (127.5 (86.8; 181) sec. vs. 98.5 (81; 193.5) sec; p= 0.04). No complication occurred. Acute success rate was 100% and there was no recurrence during the follow up. Conclusions In our randomized trial enrolled 65 patients underwent SP ablation due to AVNRT, EAM-guided approach reduced fluoroscopy time and fluoroscopy dose, however total procedural, puncture-to-mapping time, as well as total ablation time was longer compared to the ICE-guided group.