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Abnormal vascular responses to exercise in patients with aortic stenosis
The Journal of Clinical Investigation
|May 1, 1973
Summary
Patients with aortic stenosis show reversed forearm vasoconstriction during leg exercise, potentially due to left ventricular baroreceptor activation. This may explain exertional syncope in aortic stenosis patients.
Area of Science:
- Cardiovascular Physiology
- Clinical Medicine
Background:
- The normal response to leg exercise involves forearm vasoconstriction.
- Aortic stenosis (AS) may alter this response due to baroreceptor activation.
Purpose of the Study:
- To investigate forearm vascular responses during leg exercise in patients with aortic stenosis.
- To determine if left ventricular baroreceptor activation plays a role in these altered responses.
Main Methods:
- Forearm vascular responses to supine leg exercise were measured.
- Patients with aortic stenosis were compared to control groups with mitral stenosis and healthy individuals.
Main Results:
- Control groups exhibited forearm vasoconstriction during exercise.
- Patients with aortic stenosis showed forearm vasodilation or no change in vascular resistance.
- Altered responses in AS were linked to increased left ventricular pressure.
- Responses normalized after aortic valve replacement in some patients.
Conclusions:
- Forearm vasoconstrictor responses are inhibited or reversed in aortic stenosis.
- Left ventricular baroreceptor activation is a likely mechanism.
- Reflex vasodilation may contribute to exertional syncope in aortic stenosis.
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