Intraoperative echocardiography and its impact on clinical outcomes of catheter reablation of typical atrial flutter

Aim. To compare the effectiveness of cavotricuspid isthmus reablation in patients with typical atrial flutter (AFL) using a standard approach and intracardiac echocardiography (ICE). Material and methods. The study included 112 patients with recurrent AFL after cavotricuspid isthmus ablation. Patients were divided into two groups based on the ICE performance potential. In the first group, 54 patients underwent ablation using ICE; in the second (control), 58 patients underwent ablation using a standard fluoroscopy technique. ICE allowed us to assess cavotricuspid isthmus structure in patients with recurrent AFL as follows: proximal isthmus >7 mm (35%), Eustachian valve base >7 mm (48%), and a non-uniform central isthmus (13%). Achievement of bidirectional conduction block in the cavotricuspid isthmus was assessed — 52/54 (96,3%) in the ICE group and 52/58 (89,7%) in the control group (P=0,27). The follow-up period was 24 months. Results. The mean procedure duration was longer in the ICE group (54,0±16,8 min) compared to the control group (46,9±11,9 min). However, the mean fluoroscopy time was significantly shorter in the ICE group — 2,9±1,1 min and 6,3±1,8 min, respectively (P=0,003). AFL recurrence after reablation was detected in 3 (5,8%) patients in the ICE group and in 8 (13,8%) individuals in the control group (P=0,21). Conclusion. During cavotricuspid isthmus reablation in patients with recurrent typical AFL, isthmus structural characteristics were identified that were likely associated with reduced ablation efficacy. The use of ICE in reablation was associated with a reduction in fluoroscopy time. However, the risk of recurrent AF is equally low with both standard imaging and with ISE.