Figure 2.

3D electroanatomic imaging. The CARTO system uses small magnets in the tip of the catheter that are able to accurately locate the tip of the catheter within a small magnetic field created by magnets placed under the patient. Using this system, the catheter is moved within the patient's heart to build a 3D shell. Activation timing can be allocated to each point that has been collected to form activation maps. The 3D representation of the left atrium with this early system is still someway from a true representation. (a, b) Demonstrate a posteroanterior and anteroposterior views of a reconstructed left atrium. Ablation lesions have been added during ablation in (c). (d) Is an activation map of the left atrium in a patient with perimitral flutter. The different colours represent isochrones of activation. The entire cycle length can be seen around the mitral annulus.