Surface mapping and magneto-electrocardiography

The heart generates magnetic fields that can be detected by body surface mapping utilizing superconducting interference device sensors giving magnetocardiograms (MCGs). The advantages of MCGs over traditional electrocardiograms (ECGs) include increased sensitivity to small signals, less interference by tissue conductivities, and presentation of direct component signals and primary currents. This section highlights the basic principles, recent advancements, and clinical application of MCGs, especially in individuals whose ECGs are not diagnostic. Indeed, MCGs have unique value in diagnosis of prenatal electrical abnormalities, baseline shift in ischemic heart disease, His potential recording, mechanisms and foci of arrhythmias. State of the art technologies for 2D and 3D reconstruction of cardiac electrical activity combined with other cardiac imaging modalities are also discussed.