P1.39 Aortic Pulse Wave Velocity: Should the Carotid — Femoral Distance be Measured on Body Surface or Estimated from Body Height?

Objective Aortic pulse wave velocity (PWV) can be biased by the measurement of carotid — femoral (c-f) distance on body surface. We wondered whether the estimation of distance according to body height could be used. Methods Three cohorts of altogether 598 subjects (mean age 58,9 years) were studied. PWV was measured by Sphygmocor device. The c-f distance was 1. measured by tape, 2. estimated: height was multiplied by 0,27 (= median ratio of measured c-f distance to body height). Results Difference in PWV calculated by the two methods (measured minus estimated) increased with PWV: it was −0.2 m/s for PWV 5 m/s and +1.8 m/s for PWV 15 m/s. In multiple regression analysis, this difference depended highly significantly (p<0.0001) on PWV, weight (positive associations) and height (negative association); there were weak positive associations (p<0.05) with male gender, high LDL level and presence of cardiovascular disease and no associations with age, smoking, hypertension or diabetes. Conclusions When PWV is estimated from body height, the highest PWV values show regression to the mean. Besides PWV, anthropometric parameters are major determinants of the differences between the two methods. Estimation of c-f distance from body height would simplify the procedure and bias due to obesity and body disproportion would probably be minimized. For future use of aortic PWV, the best method of the distance assessment should be studied in larger cohorts with known cardiovascular morbidity/mortality endpoints.