A Quantitative Clinical Index for the Diagnosis of Symptomatic Coronary-Artery Disease

To evaluate the diagnostic potential of various readily available clinical procedures, 100 selected patients suspected of having coronary-artery disease were studied by both coronary cinearteriography and a selected pattern of standard tests and observations. Sixty-two patients had angiographic evidence of obstructive coronary atherosclerosis; 38 did not. Although individual clinical abnormalities were often unreliable indicators of coronary-artery disease, their diagnostic accuracy increased markedly when they were used in combination with one another to form a clinical index. This index, determined through multiple discriminant analysis, accurately diagnosed 94 of the 100 cases. The index was then applied to a prospective series of 100 similarly selected patients. Ninety-two were correctly diagnosed. In both the original study group and the prospective series, index values less than 100 were rarely associated with coronary atherosclerosis. Conversely, patients with indexes above 100 almost always had obstructive coronary-artery disease.