[Ambulatory measurement of Korotkoff sounds timing (QKD interval) in a normal population].

Ambulatory monitoring of Korotkoff sounds appearance time (QKD interval) was performed during 24 hours in 131 normal subjects (85 males, 46 females, aged 14-78 years, mean 36 +/- 15 years) with a new device (Diasys 200RK, Novacor-France). This device allows simultaneous measurements of blood pressure, heart rate and QKD interval at programmed intervals, every 15 minutes in this study. For each patient we calculated the average 24th QKD interval, the QKD interval for a systolic BP of 100 mmHg and a heart rate of 60 bt/min (QKD: 100-60), and the slope (S) of the variations of the QKD interval against systolic BP and pulse pressure (PP). Results are presented for each 10 years age group (mean +/- SD).