17 The use of half concentration saline is superior for the catheter ablation of typical atrial flutter. (16th October 2019)

• Record Type: Journal Article
• Authors: Hong, K; Glover, B
• Is Part Of: Heart. Volume 105(2019)Supplement 7
• Page Start: A15
• Page End: A15
• Publication Date: 2019-10-16
• Subjects: Heart -- Diseases -- Treatment -- Periodicals; Cardiology -- Periodicals; 616.12
• DOI: 10.1136/heartjnl-2019-ICS.17
• Languages: English
• ISSNs: 1355-6037

Abstract

Abstract : Background: Radiofrequency ablation for typical atrial flutter (AFL) is widely performed. The effectiveness of catheter ablation for AFL is typically confirmed via complete bidirectional block (BB) of the cavotricuspid isthmus (CTI). Standard irrigated radiofrequency ablation is performed using normal saline (NS, 0.9%), yet previous evidence suggests that wider and deeper lesions may be achieved by decreasing the irrigant ionic concentration with half normal saline (HNS, 0.45%). Therefore, it has yet to be determined whether HNS may alter lesion characterization in human subjects and lead to improve outcomes post-ablation. Objective: The purpose of this study was to compare the use of HNS to NS for catheter ablation of typical AFL with respect to the time taken to achieve BB, radiofrequency time, and recurrence of conduction within 30 minutes. The incidence of intraoperative complications, including steam pops and pericardial effusions, was also recorded. Methods: Patients were randomized to catheter ablation with either NS or HNS using a 4 mm irrigated catheter at a power setting of 30W. Ablation was performed with the aim of restoring sinus rhythm in patients who were in AFL. BB was confirmed by double potentials separated by an isoelectric line measuring ≥ 110 ms and evidence of conduction block using differential pacing. Results: A total of 30 patients underwent catheter ablation for typical AFL (14 HNS, 16 NS). Sinus rhythm and bidirectional block were achieved in all patients. The two groups did not differ with respect to patient age (69±10 years HNS vs. 71±15 years NS) or duration of AFL (7±6 months HNS vs. 8±5 months NS). The mean time to achieve BB using RF was 10.4±2.6 mins using HNS compared with 14.5±3.8 mins using NS (p=0.01). There was a higher incidence of steam pops amongst patients in the HNS arm (2 HNS vs. 0 NS). Conversely, recurrences of conduction were higher for patients in the NS group as compared to HNS, 3 vs. 0 respectively. Conclusion: By decreasing ionic concentration in radiofrequency ablation using HNS, the time taken to achieve BB was shorter as compared to NS. There were no major complications observed in either group, but patients undergoing catheter ablation with NS experienced an increased frequency of recurrences of conduction within 30 minutes.