Assessment of single vessel coronary artery disease

The purpose of this study was to determine the sensitivities of noninvasive tests for the diagnosis of single vessel coronary artery disease in a group of 56 patients with no infarction. Among these patients, 22 patients who underwent successful percutaneous transluminal angioplasty (PTCA) were also evaluated with non-invasive tests. The non-invasive tests were: twelve-lead electrocardiography, thallium-201 perfusion imaging (both planar and seven-pinhole tomographic) and radionuclide angiography. Electrocardiography and thallium imaging were performed during the same graded treadmill exercise while the radionuclide angiography was performed during upright bicycle exercise. Exercise electrocardiograms were abnormal in 34/56 patients (61 %). Qualitative planar thallium images were abnormal in 50/56 patients (89 %). Quantitative analysis of the tomographic thallium images was abnormal in 49/56 patients (86 %). An exercise ejection fraction < 0.56 or a new wall motion abnormality was seen in 38/56 patients (68 %). The results suggest that exercise thallium-201 myocardial scintigram is the most sensitive non-invasive stress test for the diagnosis of single vessel coronary artery disease. Exercise ECG and RI angiography showed less sensitive for detecting ischemia pre-PTCA than thallium-201, however, showed great trend toward normalization post-PTCA. (J.P.N.)