Noninvasive Imaging of Cardiac Electrical Function: Achievements, Pitfalls and Limitations

We developed a noninvasive approach to image the electrical function in the human heart. By combining magnetic resonance (MR) imaging and body surface electrocardiographic (ECG) mapping the electrical activation sequence in the atrium and ventricle is reconstructed. The multi-channel ECG mapping data is acquired from the patients´ chest. By coupling this data with the patients´ anatomy, obtained from gated MR, and by solving a nonlinear ill-posed inverse problem we imaged the activation sequence. Clinical validation has been performed in 45 patients by comparing this noninvasive approach with catheter-mapping (CARTO^TM) and conventional catheter techniques. This novel imaging approach aims at reconstructing focal and distributed electrical source patterns. We performed detailed clinical studies for sinus (normal and Wolff-Parkinson-White syndrome) and paced rhythm data. Besides the imaging of cardiac movement, perfusion and metabolism the imaging of electrical function will have a substantial clinical impact. Especially, in patients with focal atrial arrhythmias this method might become a powerful clinical diagnostic tool.