[Negative and positive imaging of myocardial infarct]

In 41 patients myocardial scintigrams were performed using 2 mCi 201T1 and 15 mCi 99mTc-diphosphate. 9 healthy persons showed no myocardial imaging with 99mTc-diphosphate and normal 201T1 scintigrams. Transmural infarctions could be documented by both isotopes, excepted lateral and apical infarctions which could only be shown by means of 99mTc-diphosphate. Non-transmural infarctions could not be identified, myocardial scars however--as was to be expected--showed only activity defects within the 201T1 scintigrams without corresponding images in the 99mTc-diphosphate scans. One patient with severe coronary heart disease showed diffuse diphosphate uptake all over the myocardium with normal 201T1 scintigram. The combined myocardial scintigraphy provides a better diagnosis, enabling an improved localisation of infarction and avoiding misinterpretations.