A comparison of 99Tcm-MIBI myocardial SPET and electron beam computed tomography in the assessment of coronary artery disease in two different age groups.

ABSTRACT

The aim of this study was to compare the clinical value of 99Tcm-MIBI single photon emission tomography (SPET) and electron beam computed tomography (EBCT) in the assessment of coronary artery disease (CAD) in different age groups. 99Tcm-MIBI SPET (stress-rest), EBCT and coronary angiography studies were performed in 64 consecutive patients with suspected CAD. The patients were classified into two groups Group A = 40 patients > 45 years of age and Group B = 24 patients < or = 45 years of age. There were 31 and 14 patients with coronary stenosis > or = 50% as determined by coronary angiography in Groups A and B, respectively. All patients (30 cases) with abnormal 99Tcm-MIBI myocardial SPET and coronary calcification detected by EBCT had significant coronary artery disease, and 93.3% of the patients with normal 99Tcm-MIBI SPET and normal EBCT had normal coronary angiography or < 50% lumen narrowing of the coronary arteries. In Group B, the sensitivity of SPET for detecting CAD was significantly 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 difference 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 coronary artery disease, the specificity of SPET was significantly higher than that of EBCT in Group A (94.1 vs 66.7%, P < 0.001). The sensitivity of SPET was 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 groups (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 99Tcm-MIBI myocardial perfusion SPET has a higher sensitivity than EBCT in the detection of CAD in patients < or = 45 years old and a higher specificity in patients > 45 years of age. A combination of SPET and EBCT may assess CAD more accurately.