A device is disclosed for determining and visualizing the perfusion of the myocardial muscle with the aid of static CCTA images. In at least one embodiment, the device includes a segmentation unit for segmenting the coronary blood vessels and the left myocardial muscle from a CCTA image of the heart; a first simulation unit for simulating the blood flow through the coronary blood vessels; and a second simulation unit by which the local perfusion of the myocardial muscle is determined on the basis of the ascertained blood flow into different regions of the myocardial muscle. The perfusion of the different regions of the myocardial muscle is visualized in a schematized image on a visualization unit. By virtue of the proposed device it is possible to dispense with further imaging examinations after the performance of a CCTA scan, thereby relieving the pressure both on the part of the physician and on the part of the patient.