Correlation of an abnormal rest 201T1 myocardial image: pathological findings in cardiac transplant recipients.

Rest myocardial 201T1 scintigraphy was undertaken in 15 males mean age 39 years (22-54) who had been accepted for cardiac transplantation. Complete pathological correlation was obtained in 14 after transplantation and in 1 who died before a suitable donor heart became available. The average time from scintigraphy to pathological evaluation was 42 days (9-103). All the 201T1 images were grossly abnormal and on the basis of these studies it was not possible to differentiate ischemic from idiopathic cardiomyopathy. Each of the three views of the 201T1 study was divided into three segments, therefore 135 areas were available for comparison (3 x 3 x 15). Eighty-eight of these were abnormal on scan and 78 of these were abnormal pathologically. The right ventricle was seen on all rest images but the degree of uptake bore no relationship to the measured thickness of the right ventricular wall. Structures such as the atrial wall and the enlarged papillary muscle were visualized in some patients. In two patients there was an improvement of the rest 201T1 image in delayed views and histologically these areas showed a mixture of muscle and fibrous tissue. The sensitivity of 201T1 imaging in this study was 89% and there was close correlation of the images with gross and microscopic pathological findings.