THE BALLISTOCARDIOGRAM IN CORONARY ARTERY DISEASE

In the absence of a clear-cut history and definite physical findings, the diagnosis of coronary artery disease often becomes a difficult task for the clinician. In the search for supplementary objective evidence, various tests have been developed as aids in the diagnostic study of these patients. The electrocardiogram has been most widely employed for this purpose. However, the resting electrocardiogram is of value only when it shows abnormalities, and it has been well established that a large percentage of patients with coronary artery disease have normal resting electrocardiograms.1In 1929 Master and Oppenheimer2introduced a test for circulatory function based on the response of the blood pressure and pulse to standard exercise. Subsequently these standards of exercise were employed to determine the effect of exercise on the electrocardiogram in patients with angina pectoris.3Considerable experience has now been obtained in the use of the Master "two-step" exercise