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To diagnose and characterize post-infarction left ventricular aneurysms, we performed exercise thallium-201 myocardial single photon emission computed tomography (SPECT) combined with selective coronary angiography and left ventriculography. The subjects consisted of 79 patients with acute myocardial infarction; 42 with anteroseptal, three with both anterior and inferior, 29 with inferior and five with posterior infarction. Visual classification of ventricular wall morphology by either a horizontal or a vertical long-axis image was designed into convergent (C), parallel (P) and divergent (D) types, according to the interrelationship between either septal and lateral wall or anterior and inferior wall, respectively. This method was applied in post-stress and delayed images, and these patients were divided into five groups (Group A-E) in accordance with varying morphological types from the post-stress to the delayed as follows: C-C (Group A, 36 patients), P-C (Group B, 8), P-P (Group C, 7), D-P (Group D, 5) and D-D (Group E, 23). A high incidence (21/23) of a left ventricular aneurysm by left ventriculography was recognized in Group E patients in comparison with other Groups. Provided that either Group D or E (all patients had anterior infarction) had left ventricular aneurysms, the diagnostic sensitivity, specificity and accuracy were 89%, 92% and 86%, respectively. Two of three patients with false negative diagnosis had only apical involvement. Furthermore, these two Groups had significantly larger defect scores as calculated by polar maps than did the other three Groups. When patients with anterior infarction with defect scores of 200 or greater were defined positive, the sensitivity, specificity and accuracy of ventricular aneurysms were 96%, 75% and 86%, respectively. One false negative case was apical infarction, and one of the two false positive cases were extensive anteroseptal infarction involving the apex. These results suggest that a left ventricular aneurysm which is important in predicting prognostic sequence could be diagnosed only by exercise SPECT, and that it could be characterized by extensive and severe apicoanterior infarction and a divergent-type ventricular wall arrangement on a post-stress SPECT image.

To evaluate coronary artery disease, a new quantitative thallium-201 (201T1)-tomographic scintigraphic score (TSS: modified Massie's score) using oxygen consumption (METS) was developed and compared with coronary angiographic score (CAG-S) in 27 patients (eight patients with normal coronary angiograms, and five, eight and six patients with one, two and three vessel disease, respectively) without previous myocardial infarction. All patients received both coronary angiography and the treadmill exercise test using 201T1-myocardial single photon emission computed tomography (SPECT) within two weeks. The redistribution area (RA) and washout rate area (WA) were derived from the circumferential profile analysis using apical (A), midventricular (M) and basal (B) short-axis images. To obtain TSS values, the sum of these values was divided both by percentage of the age-predicted maximal heart rate (%PMHR) and the METS value as follows: TSS = [RA (A, M, B) + WA (A, M, B)]/(%PMHR x METS). The results were as follows: 1. TSS values were 6.4 +- 1.6, 9.4 +/- 2.2, 24.2 +/- 12.0 and 30.6 +/- 5.0 (mean +/- SD) in normal, one, two and three vessel disease groups, respectively. Significant differences were found among each group except between two and three vessel disease groups. 2. The detectability of significant coronary artery disease was 89% (17/19) except in two patients with one vessel disease. 3. A high correlation coefficient was found between TSS (X) and CAG-S (Y), i.e., Y = 0.8X - 3.5 (r = 0.944, p less than 0.001). It was concluded that the tomographic scintigraphic score (TSS) is useful not only for detecting, multivessel disease but also for totally-evaluating its severity, extent and influence on collateral supply, and could be used for analyzing prognosis and the selection of therapeutic interventions.