The investigators wish to study the magnetic field map using magnetocardiography (MCG) in subjects undergoing computed tomographic angiography (visualization of the heart arteries using CT scanning, CTA). The main purposes is to investigate if MCG is capable of detecting the presence of obstructive coronary artery disease (CAD) as detected by CT angiography (CTA) as well if the MCG can exclude the presence of CAD as defined by CTA.