Noncontact electrophysiological measurement and imaging of the heart

Abstract

Method and system for noncontact electrophysiologic imaging of the heart. The methods may employ the magnetization and its relaxation-based measurements, sensitive or specifically sensitized to the properties of cardiac electrical activity, to determine the spatio-temporal distribution of cardiac electromagnetic field and cardiac electrical potentials, and to display such spatio-temporal distribution (image) for assisting in the identification of the regions with abnormal cardiac electrical activity. In one embodiment, the system uses external magnets, gradient magnetic fields and radio-frequency waves, such as those commonly used for MRI, to generate the magnetic resonance. The system synchronizes scanning to the cardiac cycle using a measure of cardiac activity (e.g., electrocardiogram, ultrasound, ballistocardiogram, arterial pressure or cardiac sounds) and examines the difference between the cardiac electromagnetic properties (magnetization and relaxation) modulated by the oscillating radio-frequency fields and/or gradient fields of different orientations and magnitudes in the presence and absence of the cardiac electrical currents.

Dependencies are inferred from the claim text.