Accuracy of left atrial anatomical maps acquired with a multielectrode catheter during catheter ablation for atrial fibrillation.

INTRODUCTION: Left atrial geometry provided by preprocedural MRI/CT imaging studies is often used to guide pulmonary vein isolation. Rapid 3D reconstruction of the left atrium (LA) can be obtained using multielectrode catheters in conjunction with electro-anatomical mapping (EAM) and can also be used to guide ablation. The objective of this study is to assess the accuracy of electro-anatomical left atrial maps acquired with the multispine catheter by comparing them to CT and MRI images.

METHODS: Forty patients undergoing ablation for atrial fibrillation were studied. All patients underwent preprocedural CT/MRI imaging. 3D reconstructions of the LA were obtained using a multispine catheter with the Ensite/NavX mapping system. The operator was blinded to the results of the preprocedural imaging studies while acquiring the LA maps.

RESULTS: Mean map acquisition time was 10.3 ± 3.0 min. There was a strong correlation between maximum pulmonary vein (PV) ostial length and intervein distances measured on the electro-anatomical maps and on the CT/MRI images. Moreover, 11 patients had right middle PVs which were detected during map acquisition. Six out of nine (67%) early branches of the right inferior PV and three out of three (100%) early branches of right superior PV were also identified. In two patients, one branch of the left superior PV and one branch of the left inferior PV were not detected during mapping.

CONCLUSION: Left atrial anatomical maps acquired using multielectrode catheters in conjunction with EAM are accurate and provide information regarding pulmonary vein dimensions and geometry which is similar to that obtained with CT/MR imaging.