A magnetocardiograph (MCG) is a device capable of recording of magnetic fields arising from the electrical activity of the heart with traces similar to an electrocardiogram (ECG). This system was developed as a noninvasive, non-contact diagnostics of obstructive coronary artery disease (CAD), and especially of lack of oxygen in the heart as in a heart attack. The overall objective of this study is to demonstrate the efficacy of this MCG device for the detection and diagnosis of lack of oxygen of the heart in patients with chest pain.