Central pulse pressure but not brachial blood pressure is the predominant factor affecting aortic arterial stiffness

XIAO Wenkai; YE Ping; BAI Yongyi; LUO Leiming; WU Hongmei; GAO Peng

doi:10.3969/j.issn.1673-4254.2015.01.07

Abstract：Objective To investigate the differences in central hemodynamic indices between hypertensive and normotensive subjects and identify the blood pressure index that the most strongly correlate with arterial stiffness and vascular damage markers. Methods A cohort of 820 hypertensive patients and 820 normotensive individuals matched for age and gender were enrolled in this study. We measured carotid-femoral and carotid-radial pulse wave velocity (PWV), aortic augmentation index (AIx) and central blood pressures using pulse wave analysis and applanation tonometry. Plasma homocysteine (HCY), high-sensitivity C-reactive protein (hsCRP) and N-terminal pro-B-type natriuretic peptide (NT-proBNP) were also tested in these subjects. Results In both hypertensive and normotensive subjects, the central systolic blood pressure (SBP) and pulse pressure (PP) were significantly lower than brachial SBP and PP; this PP amplification was significantly lower in the normotensives (9.85 ± 6.55 mmHg) than in the hypertensives (12.64 ± 6.69 mmHg), but the amplification ratios were comparable between the two groups. Blood pressure and age were closely related with aortic arterial stiffness. Compared with normotensive subjects, hypertensive subjects had higher carotid-femoral PWV and AIx, and showed significantly lowered PP amplification ratio with age. Central PP was more strongly related to arterial stiffness and vascular damage markers than the other pressure indices. Multivariate analyses revealed that carotid-femoral PWV and aortic AIx were strongly influenced by central PP but not by the mean blood pressure or brachial PP. Conclusion The central PP is a more direct indicator of central arterial stiffness and a better marker of vascular aging than other blood pressure variables. These findings support the use of central blood pressure as a treatment target in future trials.