title: Magnetic field of atrial depolarization.
abstract: The isomagnetic maps of normal subjects and patients with right and left atrial overloading were recorded to determine the characteristic features of the magnetic field of atrial depolarization. The isomagnetic maps examined in this study indicated the instantaneous current source, which specifically localizes the current sources due to the right and left atria, respectively. The magnetic field recorded with a second derivative gradiometer clearly detected the cardiac current source from the right atrium, which is located close to the anterior chest wall, thus this method improved the diagnostic sensitivity for right atrial overloading. In patients with left atrial overloading, the isomagnetic map showed multiple dipoles due to the right and left atria, respectively, which are difficult to be detected by the electrocardiogram or isopotential map. These results suggest that the magnetocardiogram provides useful information on the current source to supplement information obtained by the conventional electrocardiogram.
authors.affiliation: Second Department of Internal Medicine, School of Medicine, University of Tokushima, Japan.
authors.forename: A
authors.initials: A
authors.lastname: Takeuchi
authors.forename: K
authors.initials: K
authors.lastname: Watanabe
authors.forename: M
authors.initials: M
authors.lastname: Katayama
authors.forename: M
authors.initials: M
authors.lastname: Nomura
authors.forename: Y
authors.initials: Y
authors.lastname: Nakaya
authors.forename: H
authors.initials: H
authors.lastname: Mori
mesh_terms: D000328:Adult; D016275:Atrial Function; D004562:Electrocardiography; D004574:Electromagnetic Fields; D055590:Electromagnetic Phenomena; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009200:Myocardial Contraction