What Is Pulse Wave Velocity, and What Does Arterial Stiffness Mean?

Pulse wave velocity (PWV) is how fast the pressure wave from each heartbeat travels along your arteries, in metres per second (m/s). Healthy, elastic arteries stretch with each beat and the wave moves slowly; stiff arteries don’t, and the wave moves faster. Arteries stiffen with age, high blood pressure, and diabetes, and stiffness predicts heart attacks and strokes beyond the usual risk factors.

This article is general information, not medical advice.

How It’s Measured

The reference measurement is carotid-femoral PWV: sensors at the neck and the groin time the pulse’s arrival at each, and the distance between them divided by the delay gives the speed along the aorta. It takes a trained operator and a few minutes lying down.

Some smart scales now estimate it at home. A Withings scale, for example, times the arrival of the pulse in your feet against the moment your heart ejects blood, which it senses from tiny movements of your body on the scale. In a validation study by Campo and colleagues, the scale’s estimate agreed with a clinic device with a small average bias of 0.25 m/s, but an individual reading could differ from it by more than 1 m/s either way. Several of the study’s authors worked for the scale’s maker. Like any home estimate, it’s best for following your own trend, not for diagnosis.

What the Numbers Mean

• Age matters most. The Reference Values for Arterial Stiffness’ Collaboration measured over 16,000 people in Europe, and found that healthy PWV rose steadily with age, from around 6 to 7 m/s in people under 30 to about 10 m/s or more past 70, and faster still with high blood pressure.
• Above 10 m/s carotid-femoral PWV is a sign of organ damage from high blood pressure in the European Society of Cardiology and European Society of Hypertension’s 2018 guidelines.
• It predicts events. In a meta-analysis of 17,635 people, Ben-Shlomo and colleagues found that each standard deviation higher of aortic PWV went with a 35% higher risk of coronary heart disease and a 54% higher risk of stroke, after age and sex. It improved risk prediction over standard risk factors, and the link was strongest in younger people.

What Moves It

Blood pressure on the day of the measurement raises PWV, since a fuller artery is stiffer, so a high reading after a stressful morning may not mean much. Over the longer term, lowering high blood pressure, regular aerobic exercise, not smoking, and managing diabetes slow the stiffening that comes with age.

Following It in Kaizora

Pulse Wave Velocity is on the Vitals page; Withings scales that measure it sync it with your weigh-ins. It’s averaged, so a month’s value is the average of its readings, and since a single reading can be off by a metre per second, the monthly trend is the one to watch. Putting it beside Systolic Blood Pressure on Correlations shows whether the two move together. See Importing From Withings.

The Short Version

• PWV is the speed of the pulse along your arteries; stiffer arteries make it faster.
• It rises with age; above 10 m/s at the aorta is a sign of damage in European guidelines.
• Higher PWV predicts heart disease and stroke beyond standard risk factors.
• Home scales estimate it well enough to follow a trend, not to diagnose.

Sources

• Campo D et al., “Measurement of aortic pulse wave velocity with a connected bathroom scale,” American Journal of Hypertension 30, no. 9 (2017): 876–883. doi:10.1093/ajh/hpx059
• Reference Values for Arterial Stiffness’ Collaboration, “Determinants of pulse wave velocity in healthy people and in the presence of cardiovascular risk factors: ‘establishing normal and reference values’,” European Heart Journal 31, no. 19 (2010): 2338–2350. doi:10.1093/eurheartj/ehq165
• Williams B et al., “2018 ESC/ESH Guidelines for the management of arterial hypertension,” European Heart Journal 39, no. 33 (2018): 3021–3104. doi:10.1093/eurheartj/ehy339
• Ben-Shlomo Y et al., “Aortic pulse wave velocity improves cardiovascular event prediction: an individual participant meta-analysis of prospective observational data from 17,635 subjects,” Journal of the American College of Cardiology 63, no. 7 (2014): 636–646. doi:10.1016/j.jacc.2013.09.063