Abstract
We previously evaluated the usefulness of visual abnormalities on myocardial stress-perfusion scintigraphy (SPS) not related to the pattern of cardiac perfusion (1). These supplementary indicators (SI) included: increased lung and ventricular basal uptake and a stress related increase in left ventricular size. In a study population of 72 randomly selected patients, artifactual production of SI was achieved by changes in our imaging parameters. Through increases in imaging intensities and time of acquisition, all SI were created. Similar effects were observed with increased count rates. Acquiring images at greater distances than direct patient contact affected ventricular size and basal uptake. Angulation differences affected both these SI and the interpretation of the extent of existing perfusion defects. Ventricular size differences were seen when comparisons of stress images were done with the same redistribution projections acquired on a different camera system. Unless technical accuracy is assured there is risk in using SI to help identify patients with coronary artery disease (CAD).