Bridging noninvasive and interventional electroanatomical imaging: role of magnetocardiography

New “magnetic” technologies for intracardiac three-dimensional electroanatomical imaging (3D-EAI) have been recently developed, which have proven useful to localize the arrhythmogenic targets, to improve the outcome of ablation procedures and to reduce patient irradiation. However their 3D imaging capability cannot be used for preoperative localization of arrhythmogenic substrates. Magnetocardiographic mapping (MCG) is a more feasible and reproducible method to provide non-invasive 3D-EAI of cardiac sources. MCG detection and 3D study of arrhythmias can be enhanced by simultaneous electrophysiologic study with trans-esophageal atrial pacing and by combining MCG with minimally invasive single-catheter, multiple monophasic action potential recording, which provides a better understanding of local arrhythmogenic mechanisms underlying abnormal MCG patterns. MCG is also feasible for non-fluoroscopic imaging of amagnetic catheters in the heart. Furthermore providing 3D numerical coordinates of arrythmogenic targets, MCG could be used to program robotic magnetic navigation and to automatically guide ablation catheters or aimed endomyocardial biopsy.