Rapid myocardial perfusion imaging with⁹⁹Tc^m-teboroxime and a three-headed spect system: A comparative study with²⁰¹T1

⁹⁹Tc^m-teboroxime is a new myocardial perfusion agent with a high first pass extraction and rapid myocardial washout. The usefulness of⁹⁹Tc^m-teboroxime was evaluated for detection of myocardial ischaemia using a three-headed single photon emission tomography (SPECT) system which allows for rapid data acquisition. The subjects consisted of 14 patients, including seven with ischaemic heart disease, four with cardiomyopathy and three others. After the⁹⁹Tc^m-teboroxime injection, dynamic data was collected every minute for 15 min with continuous rotation. High-quality SPECT images could be obtained by reconstructing the serial scans from 2 to 8 min. The sensitivity, specificity and accuracy of the⁹⁹Tc^m-teboroxime study for the detection of the ischaemic region were not significantly different from those of the²⁰¹T1 study. Myocardial clearance was slow in the ischaemic lesion and in the myocardium of cardiomyopathy patients, while the coronary angiograms did not show any abnormality. These results therefore indicate that the rapid SPECT imaging and myocardial clearance of⁹⁹Tc^m-teboroxime obtained with a three-headed SPECT system were useful for the detection of myocardial ischaemia.