By a CPU (101) of a device (100) for processing medical image, a coronary artery region and a cardiac muscle region that are to be analyzed are extracted from angiographic images of the coronary artery obtained from X-ray CT images or the like. Next, degrees of isolation (blood vessel dependences), which indicate the effects of the coronary artery on the individual sites of the myocardium, are calculated. The calculated degrees of isolation are referred to as pixel values and displayed while superimposed on a bull's eye map of the cardiac muscle, a three-dimensional image of the heart or the like. As a result, the effect of infarction or constriction on the cardiac muscle region can be visually recognized merely by using the angiographic image data of the coronary artery without conducting a delay angiographic imaging examination or the like.