Pulsatile and steady 24-h blood pressure components as determinants of left ventricular mass in young and middle-aged essential hypertensives.

In order to explore the relations between left ventricular mass (LVM) and the pulsatile (pulse pressure) and steady (mean pressure) components of the blood pressure (BP) curve, 304 young and middle-aged essential hypertensive patients were studied by means of 24-h ambulatory BP monitoring and echocardiography. In the overall study population, both the BP components showed significant correlations with LVM. These correlations were unevenly distributed in the subgroups of subjects younger and in those older than 50 years. While in this latter subgroup, in multivariate analysis, both 24-h mean BP (24-MBP) (beta = 0.27; P = 0.008) and 24-h pulse pressure (24-h PP) (beta = 0.23; P = 0.02) were associated with LVM, in the subset of younger hypertensives only 24-h MBP (beta = 0.21; P = 0.009) was related to LVM, independent of other covariates. The relations observed between 24-h PP and LVM in the entire study population and in the patients older than 50 years lost statistical significance when the effect of 24-h systolic blood pressure (24-h SBP) was taken into account, in a multiple regression model in which 24-h MBP was replaced by 24-h SBP. Our findings seem to suggest that the association of PP with LVM in middle-aged hypertensives may partially explain the increased cardiovascular risk, documented in subjects with high PP. However, this relation is not independent, but is mediated by SBP.