[Tl-201 single-photon emission computed tomography for clinical assessment of dilated cardiomyopathy].
In some cases of dilated cardiomyopathy (DCM) perfusion defects are demonstrable by Tl-201 imaging at rest. This study clarified the mechanism by which the Tl scan can show myocardial perfusion defects in patients with DCM by means of Tl-201 single-photon emission computed tomography (ECT) utilizing a rotating gamma camera to assess three-dimensional T1 distribution in the myocardium. Thirteen patients with DCM were studied by conventional planar and ECT imaging, and the degree of defects was determined visually. Perfusion defects were observed in 11 of 13 cases (85%) by planar imaging and in all 13 (100%) by ECT imaging. The mean defect score was higher in ECT than in planar imaging (4.15 +/- 1.46 vs 2.23 +/- 1.46, p less than 0.025). A comparative study of defect scores and left ventricular ejection fractions (EF) using gated cardiac blood pool scans established a negative correlation on ECT imaging (r= -0.64), and no correlation on planar imaging (r= -0.38). There was no statistically significant correlation between perfusion defects on planar imaging and regional wall motion abnormalities as observed by two-dimensional echocardiography (2-DE). In contrast, most of the segments with severe defects (defect score greater than or equal to 2) on ECT images showed high grade wall motion abnormalities on 2-DE. Both perfusion defects and wall motion abnormalities in DCM may be closely related to the fibrosis or scar formation in the myocardium. These results indicated that T1-201 myocardial scintigraphy, especially ECT imaging, is of great value in the clinical assessment of patients with DCM.
D000328:Adult; D000368:Aged; D002311:Cardiomyopathy, Dilated / Q000000981:diagnostic imaging*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011868:Radioisotopes; D013793:Thallium; D014055:Tomography, Emission-Computed
D011868:Radioisotopes; D013793:Thallium