[Quantitative Tl-201 scintigraphy in diagnosis of severity and location of coronary artery disease. Comparison of a Tl-score to invasive and non-invasive parameters (author's transl)].

Thallium-201 scintigraphy was performed in 20 normals and 60 patients (pts) with angiographically proven coronary artery disease (CAD) at rest after maximal exercise for evaluation of severity and location of CAD. The Tl-scintigrams were quantified by a Tl-score. The results of the Tl-score were compared with invasive and non-invasive parameters. Sensitivity asnd specificity of the Tl-score in evaluation of CAD was 90%. In normals, there were no significant differences from rest to exercise (Tl-score less than or equal to 1.2). Twenty-six of the pts with CAD, who had no evidence of myocardial infarction, showed a significant increase of Tl-score from 5.0 +/- 1.7 to 8.7 +/- 2.6 after exercise (p < 0.001). In 34 pts with CAD and a history of MI, Tl-score increased from 24.9 +/- 3.1 to 33.3 +/- 3.8 (p < 0.001). Exercised-induced ischemia was assessed by exercise electrocardiography in 48%, by Tl-score in 62% and by angina pectoris in 77%. In 37 pts, the Tl-score was compared with the coronary score, ejection fraction (EF) and local wall motion derived from biplane cineventriculograms. There was a significant correlation between the Tl-score and the EF: y = 79.13 - 1.11 x, n = 74, r = 0.688 (p < 0.001). No correlation was found between the coronary score and the Tl-score. Hypokinetic wall motion disturbances were assessed by Tl-score in 34% only, whereas akinesia and dyskinesia were detected in 86% (p < 0.001). The data suggest that Tl-scintigraphy even with a quantitative Tl-score is not sufficient for exact assessment of extent and severity of CAD.