Determination of arterial compliance using blood pressure waveform analysis with the CR-2000 system: Reliability, repeatability, and establishment of normal values for healthy European population--the seven European sites study (SESS).

BACKGROUND: We determined the reliability and repeatability of measurements of arterial compliance (AC) and gender- and age-specific normal ranges for a healthy European population.
METHODS: Three hundred eight healthy volunteers from seven sites were evaluated. Two measurements were taken during the first visit, repeated on a second visit 1 to 4 weeks later. We used the HDI/PulseWave CR-2000 for measurements of AC.
RESULTS: Intravisit measurements, taken 5 min apart, differed by less than 3% (range, 0.36% to 2.97%). All intervisit measures differed by less than 4% (range, 0.24% to 3.67%); none of these differences was statistically significant. All correlation coefficients for pairs of AC parameters measured 5 min apart at the same visit were significant at P < .0001. Paired AC parameters at visit 1 and 2 were highly correlated (P < .0001). Repeated measures GLM (general linear model) failed to detect a significant association between either of the AC parameters and visit (first or second), time (first or second measure at the same visit), and visit-by-time (the interaction of the two preceding factors), suggesting that order of measure had no effect on the final value. Analysis of reliability was used to develop a strictly parallel model estimate of unbiased reliability. Both intravisit and intervisit estimates of reliability indicate good repeatability of measure and were significant (P < .0001). The AC values were found to differ significantly by age group, with an inverse association between each of the AC parameters and age group.
CONCLUSIONS: Measurement of the arterial waveform with the CR-2000 system is highly reproducible in healthy subjects.