Detection of ischemic responses during treadmill exercise by computer-aided impedance cardiography

The hemodynamic response to treadmill exercise by electrocardiography, impedance cardiography, and Doppler echocardiography is measured to compare the ability of these methods to detect coronary artery disease (CAD). Thirty-one hospitalized male patients with chest pain syndromes admitted for elective coronary angiography are monitored before, during, and after performing a Bruce or modified Bruce treadmill protocol. A personal computer system is used for acquisition, processing, and graphic analysis of the cardiac signals. By coronary angiography, patients were classified as having zero, one, two, three, or left-main CAD. By analysis of maximal exercise response (X_max-X_rest), aortic acceleration indices by both Doppler and impedance methods are shown to be the most sensitive indicators of CAD (P<0.05)