Jacques Clementy

Reduction in arterial distensibility in hypertensive patients as evaluated by ambulatory measurement of the QKD interval is correlated with concentric remodeling of the left ventricle

Relationships between ambulatory arterial pressure and arterial distensibility as assessed by ambulatory measure of the QKD interval and echocardiographic measurement of left ventricular mass and relative wall thickness were evaluated in a population of 163 untreated hypertensive patients. The height-corrected QKD100-60 interval was significantly correlated with left ventricular mass (LVM; r = -0.29, P<.001) and with relative wall thickness (r = -0.31, P<0.001). In a multivariate analysis, LVM was significantly correlated with mean arterial pressure, pulse pressure, and age, whereas the relative wall thickness was correlated with the QKD interval and the mean arterial pressure. The concentric character of the LVH of the hypertensive patient was thus linked to the reduction in arterial distensibility.

Alteration of arterial distensibility in systemic sclerosis

Objectives. To evaluate the distensibility of large arteries in patients with systemic sclerosis (SSc).

Ambulatory measurement of the timing of Korotkoff sounds in a group of normal subjects: influence of age and height.

Ambulatory measurement of timing of Korotkoff sounds (QKD interval) gives an estimate of arterial distensibility derived from the velocity of the pulse wave over a vascular territory that includes the ascending aorta. The main advantages of the method are that it is entirely automatic, non-operator-dependent, and highly reproducible, and produces a measure independent of instantaneous blood pressure. This study of a group of 180 normal subjects aged between 10 and 78 years was designed to produce references values and to study the influence of height. The results confirmed the reduction with age of arterial distensibility in the whole population. However before the age of 30, QKD100-60 was positively correlated with height according to the relationship QKD100-60 = 0.73 height (cm) + 91, but not with age. This equation enables calculation of the theoretical value of QKD100-60 as a function of height for any patient to which the observed value can be expressed as a percentage. This effectively eliminates the influence of height, which reflects the length of the arterial segment under investigation.

Prognostic Value of Ambulatory Measurement of the Timing of Korotkoff Sounds in Elderly Hypertensives: A Pilot Study

Alteration in the physical properties of the large arteries is probably an important contributory factor in morbidity and mortality in the elderly as well as in patients with hypertension or diabetes. We have developed a simple method based on the ambulatory measurement of the timing of Korotkoff sounds (QKD interval), together with blood pressure, to assess these properties. We report its prognostic value in a retrospective survey of elderly hypertensives. We included in this study 134 hypertensive patients over 45 years of age with no cardiovascular complications, either receiving placebo or prior to treatment with antihypertensive medication and seen between January 1992 and July 1993. In June 1995, a survey was carried out to determine outcome by contacting the patients themselves and their family physicians. Data on outcome were obtained for 111 patients with a mean follow-up period of 30 +/- 8 months. At least one cardiovascular complication was recorded during the follow-up period in 14 patients. From the Cox model, data obtained from QKD monitoring, namely the QKD(100-60), was the best predictor of complications and remained significant (P < .01) even after introduction of age, mean 24 h SBP, gender, and smoking into the model. A QKD(100-60) below 187 msec was accompanied by a relative hazard of cardiovascular complications adjusted for age and mean 24 h BP of 7.3 (95% confidence interval: 2.9 to 11.7). The indices provided by the ambulatory measurement of QKD interval are significant predictors of cardiovascular complications independently of age and BP. This new method seems to add useful information to classic ambulatory blood pressure monitoring. However this will require confirmation in a large prospective study.