Single passive leg movement-induced hyperemia: a simple vascular function assessment without a chronotropic response

Area of Science:

• Cardiovascular Physiology
• Vascular Biology
• Exercise Physiology

Background:

• Passive leg movement (PLM) is used to assess vascular function via hyperemia.
• The chronotropic response to PLM can confound results.
• A simplified method is needed to minimize central cardiovascular effects.

Purpose of the Study:

• To characterize and assess the utility of a single passive leg movement (sPLM) technique.
• To determine if sPLM can induce peripheral hyperemia while minimizing central hemodynamic responses.
• To compare sPLM with standard PLM for vascular function assessment.

Main Methods:

• 12 healthy subjects underwent standard PLM (1 Hz for 60s) and sPLM (single movement over 1s).
• Measurements included heart rate (HR), stroke volume, cardiac output (CO), mean arterial pressure (MAP), and leg blood flow (LBF).
• Leg vascular conductance (LVC) was calculated.

Main Results:

• sPLM induced a similar transient decrease in MAP as standard PLM (5 mmHg).
• Unlike standard PLM, sPLM did not elicit significant changes in HR or CO.
• Peak LBF and LVC responses were comparable between standard PLM and sPLM.

Conclusions:

• sPLM is a simplified method for assessing vascular function.
• sPLM effectively induces peripheral hyperemia without confounding chronotropic responses.
• This technique may offer a more clinically applicable tool for vascular assessment.