Reflected rather than forward wave pressures account for brachial pressure-independent relations between aortic pressure and end-organ changes in an African community. Issue 10 (October 2015)

• Record Type: Journal Article
• Authors: Sibiya, Moekanyi J.; Woodiwiss, Angela J.; Booysen, Hendrik L.; Raymond, Andrew; Millen, Aletta M.E.; Maseko, Muzi J.; Majane, Olebogeng H.I.; Sareli, Pinhas; Libhaber, Elena; Norton, Gavin R.
• Is Part Of: Journal of hypertension. Volume 33:Issue 10(2015:Oct.)
• Publication Date: 2015-10
• Subjects: aortic pressure -- end organ changes -- forward waves -- reflected waves; Hypertension -- Periodicals; Hypertension -- Periodicals; 616.132005
• DOI: 10.1097/HJH.0000000000000682
• Languages: English
• ISSNs: 1473-5598

Abstract

Abstract : Aims: To determine whether brachial blood pressure (BP)-independent relations between aortic pressure and cardiovascular damage are better explained by reflected (backward) (Pb) or forward (Pf) wave pressure effects. Methods: In 1174 participants from a community of African ancestry, we assessed central aortic pulse pressure (PPc), Pb, and Pf (radial applanation tonometry, SphygmoCor) as well as left ventricular mass index (LVMI) ( n = 786), aortic pulse wave velocity (PWV) ( n = 1019), carotid intima-media thickness (IMT) ( n = 578), transmitral early-to-late left ventricular diastolic velocity (E/A) ( n = 779) and estimated glomerular filtration rate (eGFR) ( n = 1174). Results: Independent of mean arterial pressure and confounders, PPc, and both Pb and Pf were associated with end-organ measures or damage ( P < 0.05 to P < 0.0001). With adjustments for brachial PP and confounders, Pb remained directly associated with LVMI (partial r = 0.09, P < 0.01), PWV (partial r = 0.28, P < 0.0001), and IMT (partial r = 0.28, P < 0.0001), and inversely associated with E/A (partial r = −0.31, P < 0.0001) and eGFR (partial r = −0.14, P < 0.0001). Similar relations were noted with the presence of end-organ damage ( P < 0.05 to P < 0.0001). In contrast, with adjustments for brachial PP and confounders, Pf no longer retained direct relations with LVMI, PWV, and IMT or inverse relations with E/A and eGFR. Adjustments for Pb, but not Pf, diminished brachial PP-independent relationships between PPc and end-organ measures. Independent relations between Pb, but not Pf and end-organ measures, were largely attributed to Pb accounting for most of the variation in brachial-to-aortic PP amplification. Conclusions: In communities of African ancestry, brachial BP-independent relations between aortic pressure and end-organ changes are largely attributed to an impact of reflected rather than forward wave pressures. Abstract : Supplemental Digital Content is available in the text