and remains visible during conventional radiography after the marking 103 has been formed and the proximate tissue has been contemporaneously treated in some manner the working well balloon 7 is moved to an adjacent location the term u201c contemporaneous u201d as used herein is intended to refer to acts which occur at the same time or approximately the same time for example acts which occur within a few seconds to a few minutes of each other are considered to be contemporaneous the procedure is repeated and another radiographically viewable marking 103 is produced in the myocardial muscle tissue 28 by injecting the radiographic contrast agent this process is repeated to create a map of treated tissue locations which are radiographically viewed during the entire procedure the term u201c radiographic u201d procedure as used herein is intended to include but is not limited to common fluoroscopy the portion of the heart marked in this manner could be a portion of the heart muscle that is not receiving adequate blood supply and nourishment such as oxygen because of a plaque blockage in an artery in that case it is assumed that the patient may be in need of conventional coronary bypass surgery or a conventional angioplasty procedure coronary bypass surgery which includes insertion of a suitable blood vessel extending from the aorta beyond the plaque blockage to a segment of the blood vessel beyond the blockage to provide nourishment to myocardial tissue that is being starved as a result of the blockage in accordance with one embodiment of the present invention the amount of radiographic contrast agent injected at each treatment site may be sufficient to cause ischemia injury in the tissue proximate to each stain spot 103 the.