Author + information
- Received November 16, 1982
- Revision received February 21, 1983
- Accepted March 2, 1983
- Published online July 1, 1983.
- John R. Stratton, MD, FACC*,1,
- Jeffrey B. Halter, MD†,
- Alfred P. Hallstrom, PhD‡,
- James H. Caldwell, MD* and
- James L. Ritchie, MD, FACC*
- ↵1Address for reprints: John R. Stratton, MD, Cardiovascular Disease Section (111), Veterans Administration Medical Center, 4435 Beacon Avenue South, Seattle, Washington 98108.
Serial hemodynamic and plasma catecholamine responses were compared among 10 healthy men (27 ± 3 years) ( ± 1 standard deviation) during symptom-limited handgrip (33% maximal voluntary contraction for 4.4 ± 1.8 minutes), cold pressor testing (6 minutes) and symptom-limited supine bicycle exercise (22 ± 5 minutes). Plasma catecholamine concentrations were measured by radioenzymatic assays; ejection fraction and changes in cardiac volumes were assessed by equilibrium radionuclide angiography. During maximal supine exercise, plasma norepinephrine and epinephrine concentrations increased three to six times more than during either symptom-limited handgrip or cold pressor testing. Additionally, increases in heart rate, systolic blood pressure, rate-pressure product, stroke volume, ejection fraction and cardiac output were significantly greater during bicycle exercise than during the other two tests. A decrease in ejection fraction of 0.05 units or more was common in young normal subjects during the first 2 minutes of cold pressor testing (6 of 10 subjects) or at symptom-limited handgrip (3 of 10), but never occurred during maximal supine bicycle exercise.
The magnitude of hemodynamic changes with maximal supine bicycle exercise was greater, more consistent and associated with much higher sympathetic nervous system activation, making this a potentially more useful diagnostic stress than either handgrip exercise or cold pressor testing.
This study was supported by the Medical Research Service of the Veterans Administration, Washington, D.C. and Grant AG 01926 from the National Institutes of Health, Bethesda, Maryland
- Received November 16, 1982.
- Revision received February 21, 1983.
- Accepted March 2, 1983.
- American College of Cardiology Foundation