Novel ICE-guided registration strategy for integration of electroanatomical mapping with three-dimensional CT/MR images to guide catheter ablation of atrial fibrillation.

INTRODUCTION

Image integration is used in AF ablation procedures. To maximize the efficacy of image integration, it is essential to obtain good alignment between the electroanatomical map and the 3D image of the heart. In the present study, we compared an ICE-guided landmark registration with an ICE-guided focused endocardial surface registration.

METHODS AND RESULTS

In 20 patients, registration was based on posterior landmarks acquired under ICE guidance (group A); in another 20 matched patients, a new ICE-guided focused endocardial surface registration technique was used (group B). In these latter patients, a single landmark was acquired in the inferior part of the LIPV, and several surface points were recorded in the posterior area of the left PV antrum and around the antra of the right PVs. The mean ablation point-to-CT image distance was calculated in both groups. In group A, the mean landmark point-to-CT image distance was also calculated after adding the surface registration. The mean landmark point-to-CT image distance was 4.62 +/- 1.65 mm and increased to 7.66 +/- 2.44 mm when surface registration was added. The ablation point-to-CT image distance was significantly shorter in group B (1.73 +/- 0.29 mm vs 3 +/- 0.99 mm; P < 0.001).

CONCLUSIONS

This ICE-guided focused endocardial surface registration seems to be superior to landmark registration in achieving a better alignment between the CT/MR image and the electroanatomical map. The concurrent use of standard surface registration may result in rotation of the atrial chamber.