The findings of the scintigraphy of the myocardium with Technetium-99m-diphosphonate (Tc-99m-DP) of 45 patients with nearly exclusively ischaemic heart disease were compared with those of the selective coronary angiography and those of the selective coronary perfusion scintigraphy. 12 patients exhibited an enlargement of the activity in the myocardium (positive scintigramme). These cases were particularly described in this paper. The levocardiogramme proved disturbances of the motility of the walls in 6 patients. In 5 patients a positive scintigramme of the myocardium was registered. Therefore, the scintigraphy of the myocardium with Tc-99m-DP is regarded as a supplementing, non-invasive method for the diagnosis of more pronounced disturbances of the motility of the heart wall. Furthermore, positive scintigrammes of the myocardium were registered in angina pectoris, condition after aorto-coronary bypass-operation, cardiomyopathy and myocarditis. Since the scintigraphy of the myocardium with Tc-99m-DP is a sensitive method for the poor of cell lesions of the myocardium, it allows a judgment of the floridity of the myocardial process. From this among other results that the scintigraphy of the myocardium may be a help for the indication to the aorto-coronary bypass operation. Clear relations between the scintigraphy of the myocardium, the number of the coronary-sclerotically changed heart vessels and the development of stenosation are not to be established. An immediate connection between the size of the disturbance of the perfusion and the results of the scintigraphy of the myocardium is also not to be recognized.