Prospective randomised comparison of irrigated-tip and large-tip catheter ablation of cavotricuspid isthmus-dependent atrial flutter

• Published in: European heart journal Vol. 25; no. 11; pp. 963 - 969
• Main Authors: Scavée, Christophe, Jaïs, Pierre, Hsu, Li-Fern, Sanders, Prashanthan, Hocini, Meleze, Weerasooriya, Rukshen, Macle, Laurent, Raybaud, Florence, Clementy, Jacques, Haïssaguerre, Michel
• Format: Journal Article
• Language: English
• Published: Oxford Oxford University Press 01.06.2004; Oxford Publishing Limited (England)
• Subjects: Aged; Atrial flutter; Atrial Flutter - surgery; Biological and medical sciences; Cardiac dysrhythmias; Cardiology. Vascular system; Catheter ablation; Catheter Ablation - adverse effects; Catheter Ablation - instrumentation; Electrophysiology; Equipment Design; Female; Follow-Up Studies; Heart; Humans; Male; Medical sciences; Prospective Studies; Therapeutic Irrigation - methods; Prospective; Arrhythmia; Heart disease; Catheter ablation; Catheter; Cardiovascular disease; Ablation; Excitability disorder; Comparative study; Atrial flutter
• ISSN: 0195-668X; 1522-9645
• DOI: 10.1016/j.ehj.2004.03.017

Background Radiofrequency (RF) ablation of cavotricuspid isthmus (CTI) dependent flutter can be performed using different types of ablation catheters. It has been proposed that irrigated and large-tip catheters are capable of creating larger lesions, resulting in greater efficacy. This prospective, randomised clinical study compared the efficacy of irrigated and large-tip catheters of different designs. Methods Eighty patients (69 men, 66±11 years) undergoing de novo RF ablation of CTI-dependent flutter were randomised to ablation using one of the following catheters: (i) externally-irrigated \batchmode \documentclass[fleqn,10pt,legalpaper]{article} \usepackage{amssymb} \usepackage{amsfonts} \usepackage{amsmath} \pagestyle{empty} \begin{document} \((n=20)\) \end{document}, (ii) internally-cooled \batchmode \documentclass[fleqn,10pt,legalpaper]{article} \usepackage{amssymb} \usepackage{amsfonts} \usepackage{amsmath} \pagestyle{empty} \begin{document} \((n=20)\) \end{document}, (iii) single sensor, 8-mm tip \batchmode \documentclass[fleqn,10pt,legalpaper]{article} \usepackage{amssymb} \usepackage{amsfonts} \usepackage{amsmath} \pagestyle{empty} \begin{document} \((n=20)\) \end{document}, or (iv) double sensor, 8-mm tip \batchmode \documentclass[fleqn,10pt,legalpaper]{article} \usepackage{amssymb} \usepackage{amsfonts} \usepackage{amsmath} \pagestyle{empty} \begin{document} \((n=20)\) \end{document}. The study endpoint was the demonstration of bidirectional CTI conduction block within 12 min of cumulative RF delivery. Crossover to the externally-irrigated catheter was permitted if this was not achieved. The ablation and procedural parameters, safety and efficacy were compared. Results The primary endpoint was achieved in 64 patients (80%), including all 20 patients randomised to the externally-irrigated catheter. Crossover was required in 16 patients: 9 initially using the internally-cooled catheter (45%), 3 using single-sensor, 8-mm-tip (15%), and 4 using double-sensor, 8-mm-tip (20%) catheters. The higher initial failure rate with the internally-cooled-tip catheter was significant compared to the externally-irrigated \batchmode \documentclass[fleqn,10pt,legalpaper]{article} \usepackage{amssymb} \usepackage{amsfonts} \usepackage{amsmath} \pagestyle{empty} \begin{document} \((p=0.001)\) \end{document} and single-sensor, 8-mm-tip \batchmode \documentclass[fleqn,10pt,legalpaper]{article} \usepackage{amssymb} \usepackage{amsfonts} \usepackage{amsmath} \pagestyle{empty} \begin{document} \((p=0.04)\) \end{document} catheters. The externally-irrigated catheter achieved the study endpoint more frequently with fewer RF applications of shorter duration compared to the internally-cooled-tip catheter and 8-mm-tip catheters, the difference being significant compared with internally cooled ablation. No major complications were observed. Conclusion Among commonly used ablation catheters, the externally-irrigated catheter has a higher efficacy for rapid achievement of CTI block.