Patterns of use and clinical utility of exercise thallium-201 single photon emission-computed tomography in a...

Single photon emission computed tomographic (SPECT) imaging with thallium-201 was evaluated in 492 consecutive, unselected patients to ascertain the patterns of use and additive value to the exercise electrocardiogram in the diagnosis of myocardial ischemia in a community hospital setting. Myocardial perfusion images were interpreted by a single observer employing visual and confirmatory quantitative analysis. The majority of patients (69%) were studied to evaluate the functional consequences of known coronary artery disease and not primarily to aid in diagnosis. Relationships among exercise electrocardiograms, SPECT information and coronary angiography were analyzed in 303 patients. The sensitivity was 92% and improved to 96% when multivessel disease was present. Overall, the positive predictive value of tomographic imaging in the detection of coronary disease was 94%. These findings demonstrate the changing pattern of use of myocardial perfusion imaging and confirm the value and applicability of this technique in routine clinical practice.