Measure arterial wave speed using flexible calculation modes. Switch units, validate data, and save outputs. Results appear instantly, ready for analysis and sharing securely.
Distance / Transit Time: PWV = L / Delta t, where L is path length and Delta t is the wave transit time.
Moens-Korteweg: PWV = sqrt( E*h / (2*rho*r) ), modeling a thin-walled elastic tube carrying an incompressible fluid.
Bramwell-Hill: PWV = sqrt( 1 / (rho*D) ), where D is distensibility in 1/Pa.
| Scenario | Method | Key inputs | PWV (m/s) |
|---|---|---|---|
| Carotid-femoral path | Distance / Transit Time | L = 0.80 m, Delta t = 0.080 s | 10.000000 |
| Elastic vessel model | Moens-Korteweg | E = 0.4 MPa, h = 1.0 mm, r = 10 mm, rho = 1060 kg/m3 | 4.345 (approx.) |
| Distensibility-based | Bramwell-Hill | rho = 1060 kg/m3, D = 1.0e-8 1/Pa | 9.708 (approx.) |
Pulse wave velocity (PWV) is the speed at which a small pressure or flow disturbance travels along a compliant conduit. In vascular physics it is often used as a stiffness proxy: lower compliance and higher effective wall tension usually increase PWV. PWV is a wave property, not a mean flow speed, so it can be estimated from timing features even when average flow is low.
The direct approach uses PWV = L / Delta t. Typical practice is to measure a path length L and a transit time Delta t between two waveforms. Because PWV depends linearly on both values, a 5% error in distance or timing produces about a 5% error in PWV.
Path length is not always a straight line. Using a surface tape measure can overestimate the true centerline length in curved geometries. As a practical data point, changing the assumed path by 2 cm on an 80 cm segment shifts PWV by 2.5% at fixed timing, which can matter when comparing sessions.
The Moens-Korteweg model estimates PWV from material and geometry: PWV = sqrt(E*h/(2*rho*r)). It highlights scaling behavior. If the elastic modulus E doubles while h, r, and rho stay constant, PWV increases by sqrt(2) (about 41%).
The Bramwell-Hill form uses compliance information: PWV = sqrt(1/(rho*D)). Distensibility D is often computed from fractional area change per pressure change. Unit consistency is critical; for example, 1 mmHg equals 133.322 Pa, so converting pressure units can change D by the same factor.
PWV is most often reported in m/s. This calculator also shows cm/s and km/h for cross-checking: 1 m/s equals 100 cm/s and 3.6 km/h. Keeping a single reporting unit across datasets prevents mix-ups when exporting CSV files for analysis.
In many adult large-artery studies, reported PWV values are commonly in the single-digit to low double-digit m/s range under resting conditions. The exact range depends on measurement site, distance definition, filtering, and population. Treat outputs as physics results, not standalone diagnoses.
For reproducible comparisons, document method selection, units, distance definition, timing feature (foot-to-foot, peak, cross-correlation), and any preprocessing. Saving a PDF alongside the raw numbers helps keep assumptions visible when the calculation is revisited months later.
Use Distance / Transit Time when you have measured path length and timing. Use Moens-Korteweg when you have elastic modulus and geometry. Use Bramwell-Hill when you can estimate distensibility from pressure and area changes.
They describe different measurement models and assumptions. Direct timing reflects your waveform processing and path choice. Moens-Korteweg assumes a thin, linear elastic wall. Bramwell-Hill depends on how distensibility is estimated and pressure units.
Distensibility is the fractional area (or volume) change per unit pressure change. A common form is D = (DeltaA/A)/DeltaP. Smaller distensibility means a stiffer system, which increases PWV for the same fluid density.
Very sensitive when transit times are small. If Delta t is 40 ms, a 2 ms timing uncertainty is 5% and becomes a 5% PWV uncertainty. Improve sampling rate and choose a stable waveform feature to reduce jitter.
Yes. The same wave-speed ideas apply to tubes, hoses, and compliant conduits in engineering. Select the method matching your available parameters and ensure the assumptions fit your system, especially wall thickness, linearity, and fluid compressibility.
It assumes a thin-walled tube, small deformations, and linear elastic behavior. Real systems can have viscoelasticity, nonuniform thickness, and complex boundary conditions. Use it as an estimate and compare against direct timing when possible.
Include the selected method, the numeric PWV in a single primary unit, and the exact inputs with units. Also record how distance and transit time were defined. The CSV and PDF outputs help keep those details attached to the number.
Important Note: All the Calculators listed in this site are for educational purpose only and we do not guarentee the accuracy of results. Please do consult with other sources as well.