Robotic versus conventional ablation for common-type atrial flutter: a prospective randomized trial to evaluate the effectiveness of remote catheter navigation

BACKGROUND: Conventional catheter ablation for common-type atrial flutter (AFL) is a widely established therapy but has not been compared with the use of a robotic navigation system (RNS) thus far.

OBJECTIVES: The purpose of this study was to investigate the feasibility of a new, nonmagnetic RNS with regard to safety, efficacy, and X-ray exposure to investigator and patient compared with the conventional ablation approach in patients with AFL.

METHODS: Fifty patients (65.7 +/- 9.3 years, 40 male) undergoing de novo catheter ablation for AFL were randomly assigned to conventional or RNS-guided cavotricuspid isthmus (CTI) ablation.

RESULTS: Complete bidirectional isthmus block was achieved for all patients without occurrence of procedure-related complications. The fluoroscopy time and the investigator X-ray exposure (8.2 +/- 4.6 vs. 5.8 +/- 3.6, P = .038; and 8.2 +/- 4.6 vs. 1.9 +/- 1.1 minutes, P<.001) as well as the mean radiofrequency (RF) duration and the energy delivered were significantly higher in the conventional than in the RNS group (321.7 +/- 214.6 vs. 496.4 +/- 213.9 seconds, P = .006; 8279 +/- 5767 vs. 16,308 +/- 6870 J, P<.001, respectively). The overall procedure time in the RNS group was significantly longer than in the conventional group (79.2 +/- 30.6 vs. 58.4 +/- 17.7 minutes; P = .04) but significantly decreased comparing the first 10 with the last 10 patients in the RNS group (105.3 +/- 34.8 vs. 60.6 +/- 6.3 minutes; P = .003). Starting ablation during AFL, bidirectional block instantly after termination was observed in 90% of the RNS and 50% of the conventionally treated patients (P = .03).

CONCLUSION: The present study demonstrates the safety and feasibility of RNS for performing CTI ablation in patients with common-type AFL for use in the clinical routine. As a result of the remote navigation, X-ray exposure and RF duration to achieve bidirectional block were significantly decreased and occurred more often immediately after AFL termination. These findings are consistent with increased catheter stability and RF application efficacy using RNS compared with conventional catheter manipulation.