Myocardial tagging is a technique that is useful in assessing ventricular function. By modulating the magnetization gradient, the signal from the myocardium can be nulled in a grid pattern prior to the onset of image acquisition.  At imaging, this dark appearing grid moves with the tissue that was tagged by the null signal.  Areas of myocardium that are not contracting appropriately will demonstrate decreased deformation of the grid during the cardiac cycle.

Additionally, tagging can be applied to imaging of pericardial disease to evaluate for areas of thickened pericardium adhered to the myocardium.