A comparison of Tc-99(m)-MIBI myocardial SPET and electron beam computed tomography in the assessment of coronary artery disease in two different agegroups

The aim of this study was to compare the clinical value of Tc-99(m)-MIBI si ngle photon emission tomography (SPET) and electron beam computed tomograph y (EBCT) in the assessment of coronary artery disease (CAD) in different ag e groups. Tc-99(m)-MIBI SPET (stress-rest), EBCT and coronary angiography s tudies were performed in 64 consecutive patients with suspected CAD. The pa tients were classified into two groups: Group A = 40 patients > 45 years of age and Group B = 24 patients less than or equal to 45 years of age. There were 31 and 14 patients with coronary stenosis greater than or equal to 50 % as determined by coronary angiography in Groups A and B, respectively. Al l patients (30 cases) with abnormal Tc-99(m)-MIBI myocardial SPET and coron ary calcification detected by EBCT had significant coronary artery disease, and 93.3% of the patients with normal Tc-99(m)-MIBI SPET and normal EBCT h ad normal coronary angiography or < 50% lumen narrowing of the coronary art eries. In Group B, the sensitivity of SPET for detecting CAD was significan tly higher than that of EBCT (92.9 vs 42.9%, P < 0.01); the specificity of SPET was comparable to that of EBCT. in Group A, there was no significant d ifference between SPET and EBCT in terms of sensitivity (93.6 vs 90.3%) or specificity (88.9 vs 55.6%). However, in the detection of individual corona ry artery disease, the specificity of SPET was significantly higher than th at of EBCT in Group A (94.1 vs 66.7%, P < 0.001). The sensitivity of SPET w as again significantly higher than that of EBCT (85.7 vs 38.1%, P < 0.005) in Group B. The accuracy of SPET was higher than that of EBCT in both group s (82.5 vs 67.5%, P < 0.01 in Group A; 93.1 vs 76.4%, P < 0.01 in Group B, respectively). We conclude that Tc-99(m)-MIBI myocardial perfusion SPET has a higher sensitivity than EBCT in the detection of CAD in patients less th an or equal to 45 years old and a higher specificity in patients > 45 years of age. A combination of SPET and EBCT may assess CAD more accurately. ((C ) 2000 Lippincott Williams & Wilkins).