[Clinical usefulness of dipyridamole loading 99mTc-tetrofosmin myocardial scintigraphy]

This study performed to establish the most suitable method in one-day protocol and to evaluate clinical usefulness of 99mTc-tetrofosmin myocardial scintigraphy after dipyridamole infusion. Image quality and liver overlapping of the myocardial SPECT were evaluated in 107 patients with old myocardial infarction (42 cases), angina pectoris (53 cases) and others (12 cases). Left ventricular wall motion and coronary artery stenosis were compared to myocardial uptake score in 55 patients who received cardiac catheterization. The suitable image quality was acquired in early SPECT images using 259 MBq of 99mTc-tetrofosmin. The overlapping between inferior wall and liver uptake was able to minimize over 45 minutes interval from injection of 99mTc-tetrofosmin to data acquisition. The segments of normal wall motion had no perfusion defect of the myocardial SPECT in all cases (100% (148/148)). The segments of abnormal wall motion had decreased myocardial uptake of the myocardial SPECT (77% (24/31)). The agreement between coronary artery stenosis and decreased myocardial uptake was 96% (24/25) in right coronary artery, 87% (26/30) in left anterior descending coronary artery and 83% (19/23) in left circumflex coronary artery. These data suggests that image quality of dipyridamole loading 99mTc-tetrofosmin myocardial scintigraphy. Myocardial perfusion in the 99mTc-tetrofosmin myocardial scintigraphy is good correlation to both left ventricular wall motion and coronary artery stenosis.