SEGMENTAL ANALYSIS OF SPECT TC-99M-METHOXY ISOBUTYL ISONITRILE AND TL-201 MYOCARDIAL IMAGING IN ISCHEMIC-HEART-DISEASE

To study the potential usefulness of99mTc-methoxy isobutyl isonitrile (99mTc-MIBI) as a substitute for201Tl in assessing patients with ischaemic heart disease, 24 patients underwent 1 day rest and exercise99mTc-MIBI single photon emission computerised topography (SPECT) 1 week after SPECT exercise201Tl. All patients were catheterized within 1 month after myocardial imaging. In 17 patients, resting first pass radionuclide angiography (FPRNA) was performed with99mTc-MIBI. The heart to lung ratio for99mTc-MIBI and201Tl was calculated both at rest and exercise. The segmental analysis for myocardial perfusion reveals that 87/96 segments (91 %) were correctly classified by SPECT201Tl and 84/96 segments (88%) were correctly classified by99mTc-MIBI. A significant correlation was present between LVEF measured by99mTc-MIBI FPRNA and contrast ventriculography (r = 0.85, P < 0.0001). The heart to lung ratio both at rest and exercise for99mTc-MIBI is significantly higher than201Tl (P < 0.01 and <0.001 respectively). We conclude that99mTc-MIBI is a promising agent for simultaneous evaluation of myocardial perfusion and cardiac function. © 1990 Springer-Verlag.