ASSESSMENT OF ARTERIAL DISTENSIBILITY BY MONITORING THE TIMING OF KOROTKOFF SOUNDS - REPRODUCIBILITY

We have proposed the use of the ambulatory monitoring of the timing of Korotkoff sounds (QKD interval) to assess arterial distensibility. Th is interval is inversely linked to pulse wave velocity. The study of i ts variations according to spontaneous blood pressure changes during 2 4 h allows to calculate indices of arterial distensibility independant of actual blood pressure. A normalized QKD(100-60) is calculated as t he value for a 60 batt/min heart rate and a 100 mmHg systolic blood pr essure from the individual multivariate linear relationship between th ese 3 variables. This interval decrease with arterial distensibility. We tested the reproducibility of this method in 28 normal subjects (14 males, 14 females, aged 43 +/- 16 years) who underwent two 24 h recor dings during daily routine separated by one week. Standard deviation o f differences for QKD(100-60) was 12 ms, the coefficient of variation 6% and the coefficient of repeatibility 24 ms. So QKD(100-60) shows a good reproducibility in the same range that 24 h blood pressure means.