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The relative contribution of loading conditions at different ages across the full adult lifespan to decreases in left ventricular (LV) diastolic function is unclear. Using central arterial pressure and aortic velocity and diameter measurements in the outflow tract, we determined the contribution of systemic vascular resistance, compression wave pressures (characteristic impedance [Zc]×aortic flow [Q], [P Q×Zc ]) and backward wave pressures (Pb) to LV diastolic function (echocardiography) in a community sample across the full adult lifespan (n=605). Starting from early adulthood, stepwise age-related increases in LV filling pressures (E/e') and decreases in myocardial relaxation (e') were noted ( P <0.0001). Before 50 years of age, before when P Q×Zc positively correlates with age, Pb, but not systemic vascular resistance was independently associated with LV mass index ( P <0.002), E/e' ( P <0.002), and e' ( P <0.05). Moreover, in those over 50 years of age, when P Q×Zc positively correlates with age, again Pb, but neither P QxZc nor systemic vascular resistance was independently associated with LV mass index ( P <0.01), E/e' ( P <0.001), and e' ( P <0.001). The contribution of Pb to age-related decreases in LV diastolic function was as strong in those younger as compared with older than 50 years of age and poorly indexed by brachial BP. In conclusion, a striking age-related deterioration in LV diastolic function begins at an early adult age and Pb is the dominant hemodynamic factor that accounts for this relationship. Age-related increases in Pb in young adults contribute as much to functional abnormalities ultimately responsible for LV diastolic dysfunction in hypertension as at an older age, effects poorly indexed by brachial BP.

Background: Whether the impact of backward wave pressures (Pbs) on left ventricular (LV) diastolic dysfunction (DD) antedates the effects of aortic stiffness is uncertain. We compared the relative contribution of various aortic hemodynamic parameters to preclinical DD in a predominantly young-to-middle-aged community-based sample., Methods: In 524 randomly selected participants of African ancestry (mean age = 46.8±18.4 years), we assessed central aortic pulse pressure (PPc), forward wave pressure (Pf), Pb, augmented pressure (Pa), the time-to-wave reflection (Rt), and aortic pulse wave velocity (PWV) using applanation tonometry (SphygmoCor software). LV mass index (LVMI), early to late transmitral velocity (E/A), and E/velocity of myocardial tissue lengthening (E/e') were determined using echocardiography., Results: Independent of age, sex, mean arterial pressure, body mass index, diabetes mellitus and/or HbA1c > 6.1%, regular smoking, regular alcohol intake, treatment for hypertension, pulse rate, and LVMI; PPc (P < 0.002), Pb (P < 0.0005), Pa (P < 0.002), and Pf (P < 0.02), but not Rt or PWV were independently associated with E/e' (but not with E/A). With adjustments for confounders, PPc (P < 0.005), Pb (P < 0.002), and Pa (P < 0.001), but not Pf, Rt, or PWV were independently associated with E/e' ≥ 12 (moderate-to-severe DD, n = 69). The independent relations between PPc and E/e' or moderate-to-severe DD were not affected by adjustments for PWV, Pf, or Rt, but were abolished with adjustments for Pb., Conclusions: In a predominantly young-to-middle-aged community sample, the impact of Pbs on LV DD antedates the effects of aortic stiffness, the time-to-wave reflection, or Pfs., (© American Journal of Hypertension, Ltd 2016. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)

Although several indexes of left ventricular (LV) diastolic function show heritability, the genetic influence on the tissue Doppler index, E/e' (early transmitral velocity/velocity of myocardial tissue lengthening), an index of LV filling pressures in those of black African descent is currently unknown. Furthermore, whether any genetic influences on E/e' are through an impact of LV remodeling or aortic function is unknown. Intrafamilial aggregation and heritability (SAGE software) of E/e' (echocardiography) were assessed in 129 nuclear families (29 spouse pairs, 216 parent-child pairs, and 113 sibling-sibling pairs) from an urban developing community of black Africans, independent of LV mass index (LVMI), LV relative wall thickness (RWT), central aortic systolic pressure (SBPc), and backward wave pressures (Pb) (applanation tonometry, SphygmoCor software). Independent of confounders including LVMI and RWT, E/e' was correlated in parent-child (r = 0.23; P < .001) and sibling-sibling (r = 0.29; P < .005), but not in spouse (r = 0.13; P = .51) pairs. The relationships between parent-child (r = 0.22; P < .001) and sibling-sibling (r = 0.29; P < .005) pairs persisted with adjustments for SBPc. The relationships between parent-child (r = 0.22; P < .001) and sibling-sibling (r = 0.26; P < .01) pairs also persisted with adjustments for Pb. Independent of confounders including LVMI and RWT, E/e' showed significant heritability (h(2) ± standard error of the mean [SEM] = 0.51 ± 0.11; P < .0001) which similarly persisted with adjustments for SBPc (h(2) ± SEM = 0.50 ± 0.11; P < .0001) and Pb (h(2) ± SEM = 0.49 ± 0.11; P < .0001). In conclusion, in a group of African ancestry, independent of LV remodeling and aortic function, E/e' shows significant intrafamilial aggregation and robust heritability. Hence, genetic factors may play an important role in determining moderate-to-severe LV diastolic dysfunction independent of cardiac remodeling or aortic function in groups of black African ancestry., (Copyright © 2016 American Society of Hypertension. Published by Elsevier Inc. All rights reserved.)