Related Experiment Video
Updated: Jun 18, 2026

Doppler Ultrasound-Based Leg Blood Flow Assessment During Single-Leg Knee-Extensor Exercise in an Uncontrolled Setting
Published on: December 15, 2023
The effects of passive leg raising on arterial wave reflection in healthy adults
Haroon Kamran1, Louis Salciccioli, Jeffery Gusenburg
1Division of Cardiovascular Medicine, State University of New York Downstate Medical Center, Brooklyn, New York 11203-2098, USA.
Background:
Passive leg raising (PLR) produces hemodynamic and physiological changes related to centralizing blood volume and baroreceptor activation.
Methods/Results:
To evaluate the effects of PLR on central hemodynamics, we prospectively studied 50 healthy participants (80% male, age 37 +/- 12 years). Central aortic blood pressures (CA-BPs) and reflected wave properties were evaluated using applanation tonometry at baseline and upon 1 min of PLR. Heart rate (HR) was unchanged. Brachial artery (BA)-systolic BP, BA-diastolic BP, and BA-pulse pressure (PP) all decreased from baseline to PLR. Changes in BA-PP were significantly greater than changes in CA-PP. Reflected wave augmentation pressure (P(s)-P(i)), HR corrected augmentation index (AIx@75), and augmentation index decreased significantly [(P(s)-P(i)): 5 +/- 6 vs. 4 +/-5, P < 0.001; AIx@75%: 10 +/- 13 vs. 7 +/- 12, P = 0.004; AI%: 14 +/- 12 vs. 12 +/- 12, P = 0.014, respectively]. HR corrected ejection duration (ED(c)), round trip travel time (deltat(p)), and reflected wave systolic duration (deltat(r)) all increased upon PLR [ED(c): 433 +/- 15 vs. 444 +/- 17, P < 0.001; deltat(p): 149 +/- 18 vs. 156 +/- 20, P = 0.003; deltat(r): 174 +/- 33 vs. 179 +/- 32, P = 0.046, respectively]. Indices of left ventricular (LV) workload including wasted LV energy and tension-time index decreased upon PLR.
Conclusion:
PLR decreases the amplitude and delays the onset of the reflected aortic pressure wave. This decreases wasted LV pressure energy and workload.
Related Concept Videos
Assessing Blood pressure in the Leg
Preparation:
Peripheral Arterial Disease II: Clinical Manifestations and Diagnostic Evaluation
Special considerations while measuring blood pressure
Monitoring Both Arms:
Monitoring BP in both arms during the initial assessment is advisable, as the systolic value may differ by five to ten mm Hg between arms. For subsequent BP assessments, use the arm with the higher reading.
Pre-Procedural Guidelines for Assessing Blood Pressure
Pulse Assessment Sites
Assessment of the Cardiovascular System III: Palpation
Jugular Venous Pressure (JVP) Measurement
Position the patient at a thirty- to forty-five-degree angle or in a semi-fowler's position. Look for the highest point of pulsation in the internal jugular vein and measure the vertical distance to the angle of Loius or sternal angle. A normal JVP is 3-4 cm above the...

