Comparing Low-to-Zero Fluoroscopic Navigation Systems for AVNRT Catheter Ablation: A Network Meta-Analysis.

Background: Low-to-zero fluoroscopic navigation systems lower radiation exposure which improves health outcomes. Conventional x-ray fluoroscopy (CF) has long been the standard to guide to catheter location for cardiac ablation. With advancements in technology, alternative safety navigation systems have been developed. Three primary modalities commonly utilized are three-dimensional electroanatomic mapping (3D-EAM), magnetic navigation system (MNS), and intracardiac echocardiography (ICE), all of which can reduce radiation exposure during the procedure.

Objective: We aim to compare the efficacy and safety among ICE, EAM, MNS, and CF in ablation of atrioventricular nodal reentrant tachycardia (AVNRT).

Methods: This is a meta-analysis consisting of observational studies and randomized controlled trials, which evaluated the performance of navigation systems of catheter ablation in AVNRT patients. Primary endpoint was to access the AVNRT recurrence after the procedure during follow-up periods. Secondary endpoints were technical success, fluoroscopic time, fluoroscopic dose area product, radiofrequency ablation time, and adverse events. Random-effect model was applied for pooled estimated effects of included studies.

Results: A total of 21 studies (21 CF, 2 ICE, 9 EAM, 11 MNS) including 1716 patients who underwent catheter ablation for AVNRT treatment were analyzed. Of these, 16 were observational studies and 5 were randomized controlled trials.

Primary outcome: Point estimation of AVNRT recurrence showed ICE exhibited a pooled odds ratio (ORs) of 1.06 (95% confidence interval [CI]: 0.064-17.322), MNS with ORs of 0.51 (95% CI: 0.214-1.219], and EAM with ORs of 0.394 (95% CI: 0.119-1.305) when compared to CF.

Secondary outcomes: EAM had significant higher technical success with ORs of 2.781 (95% CI: 1.317-5.872) when compared to CF. Regarding fluoroscopy time, EAM showed the lowest time with mean differences (MD) of -10.348 min (95% CI: -13.385 to -7.3101) and P-score of 0.998. It was followed by MNS with MD of -3.712 min (95% CI: -7.128 to -0.295) and P-score of 0.586, ICE with MD of -1.150 min (95% CI: -6.963 to 4.662) with a P-score of 0.294 compared to CF, which has a P-score of 0.122. There were insignificant adverse events across the procedures.

Conclusion: AVNRT ablation navigated by low-to-zero fluoroscopic navigation systems achieves higher efficacy and comparable safety to conventional fluoroscopywhile also reducing risk of radiation exposure time.