The response of the oxygen pulse during a stress test in patients with coronary artery disease.

The pattern of change of the O2 uptake . beat-1 versus the difference between the measured and predicted MET level varied considerably during a progressive exercise stress test among patients with coronary artery disease and normals. For normal subjects under work load changes from 2 to 10 MET (1 MET = resting VO2), the O2 . beat-1 approximately doubled; whereas for some patients, the value fell near the end of the stress rest to a level near that at the beginning. This parameter is one measure of the efficiency of the cardiovascular system to respond to exercise and appeared to correlate with the physiological condition of the patient.