Purpose: Electroanatomical mapping is a useful tool during the ablation of atrial fibrillation. Respiratory movement might influence the mapping accuracy and merging. This study aims to investigate the effect of respiratory gating on the accuracy of magnetic-field-based electroanatomical mapping under spontaneous respiration.
Methods: Fifty-one consecutive patients (35 male, aged 30-78 years) who underwent left atrial radiofrequency catheter ablation due to atrial fibrillation were included. Electroanatomical mapping was performed with CARTO 3 System under conscious sedation. Respiratory gating was achieved with the AccuResp algorithm (Biosense Webster). Average surface match and maximum distance of the pre-acquired and electroanatomical maps, as well as left atrial volume, were recorded with and without respiratory gating after merging.
Results: The average surface match of the electroanatomical map with the left atrial reconstruction was significantly better with respiratory gating than without using the algorithm (3.81 ± 1.09 vs 4.11 ± 1.61 mm, p = 0.0119). It was not dependent of the rhythm during mapping or the image modality used for left atrial reconstruction. The maximal distance between the two maps did not depend on the use of the algorithm (19.81 ± 6.24 mm for gated and 20.87 ± 7.99 mm for non-gated, p = 0.3161). Left atrial volume of the map was significantly lower when using the respiratory compensation module (106.3 ± 31.6 vs 127.0 ± 36.4 ml, p < 0.0001) and showed a significant correlation with the pre-recorded 3D reconstruction volumes (r = 0.66, p < 0.0001).
Conclusions: The use of the novel respiratory gating algorithm might improve the accuracy of electroanatomical mapping during left atrial ablation under conscious sedation. The possible impact on the effectiveness of the ablation needs to be further evaluated.
Keywords: Accuracy; Atrial fibrillation; Catheter ablation; Electroanatomical mapping; Respiratory gating; Spontaneous respiration.