Abstract 5663: Intracardiac Echocardiography From Within the Left Atrium Improves the Accuracy of Image Integration During Catheter Ablation of Atrial Fibrillation

Abstract

Background: Intracardiac echocardiography (ICE) can be integrated with pre-procedural CT or MR imaging to direct catheter ablation of atrial fibrillation (AF). Prior work has described ICE imaging of the left atrium (LA) with the ICE probe in the RA, but it is feasible to image the LA from an ICE probe placed directly into the LA via a trans-septal puncture performed for the mapping/ablation procedure. The purpose of this study was to determine whether direct LA imaging with ICE results in improved image integration during AF ablation compared with LA imaging indirectly from the RA. Methods: Twenty-five consecutive patients undergoing an AF ablation procedure with the CARTO-Sound system were studied. A 10 French phased array catheter with an embedded CARTO navigation sensor was employed to provide 2D echocardiogram images of the LA - 13 patients underwent imaging from the RA alone and 12 patients from the LA. The accuracy of the image integration was assessed by the average integration error after surface registration and the requirement to take supplementary electroanatomic mapping points to obtain acceptable image integration. Results: Twenty-five patients (56% paroxysmal AF, average LA size = 42±8 mm, average EF = 63±10 %) were examined. There was no difference in the time or number of ultrasound contours required to create a LA anatomic map with ICE imaging from the RA versus the LA (24±17min vs. 24±25min, P=1.0, 24±16 contours vs. 29±18 contours, P=0.5). The average integration error for all patients was 2.19±0.59mm. Direct LA imaging was associated with improved integration error compared to indirect LA imaging from the RA (1.85±0.33mm versus 2.51±0.62mm, P=0.004). Image integration using RA acquired LA images had a tendency to be less accurate resulting in the primary operator acquiring additional registration points to supplement the registration process (patients requiring additional registration points for registration: 3/12 for LA imaging versus 9/13 for RA imaging of the LA, P=0.05). Conclusion: Direct ICE imaging from within the LA is feasible and associated with improved accuracy of image integration during AF ablation.