Real-time integration of intracardiac echocardiography and multislice computed tomography to guide radiofrequency catheter ablation for atrial fibrillation.

Background: Multislice computed tomography (MSCT) integration is commonly used to guide radiofrequency catheter ablation (RFCA) for atrial fibrillation (AF). MSCT provides detailed anatomical information but lacks the ability to provide real-time anatomy during RFCA. Intracardiac echocardiography (ICE) allows real-time visualization of cardiac structures. Objective: The purpose of this study was to investigate the feasibility of three-dimensional (3D) anatomical mapping of the left atrium (LA) with ICE and integrating the 3D map with MSCT to facilitate RFCA for AF. Methods: In 17 patients undergoing RFCA for AF, 3D mapping of the LA was performed with ICE using a new mapping system that allows tracking of a new ICE probe. On each ICE image, endocardial contours were traced and used to generate a 3D map of the LA and pulmonary veins (PVs). A preprocedurally acquired MSCT image of the LA was then integrated with the 3D map. Additionally, PV assessment with ICE was compared with MSCT. Results: Accurate 3D mapping could be performed in all patients with a mean number of 31.1 ± 8.5 contours. Integration with MSCT resulted in a mean distance between the MSCT and ICE contours of 2.2 ± 0.3 mm for the LA and PVs together and of 1.7 ± 0.2 mm around the PV ostia specifically. Agreement in the assessment of PV anatomy and diameters between ICE and MSCT was excellent. Conclusion: Three-dimensional ICE mapping of the LA is feasible. The 3D map created with ICE can be merged with MSCT to facilitate RFCA for AF. [Copyright &y& Elsevier]