Rest gated blood pool scan (Rest GBP scan) and dipyridamole Tc-99m-MIBI SPECT were performed in 34 patients with or suspected coronary artery disease. Both studies were performed within 2∼32 days (mean 8.1 days). A significant correlation was present between left ventricular ejection fraction (r=-0.7356, p 〈0.001) and peak ejection rate and peak filling rate in rest GBP scan and perfusion defect in MIBI SPECT. And there were acceptable correlations (0.05〈p〈0.001) between regional ejection fractions and perfusion defects corresponding to the regions. There were 39 segments of fixed (rest) perfusion defects in MIBI SPECT and there was a significant difference in perfusion defect according to the regional wall motion (normal or mild hypokinesia in 23 regions: 26.2±10.8%, severe hypokinesia, akinesia or dyskinesia in 16 regions: 78.2±23.7, p〈0.001). These data indicate there is a significant coupling between the degree of myocardial perfusion and the myocardial functional change in coronary artery disease.