Cardiovascular Pathophysiology and Genomics Research Unit, School of Physiology, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa.
Am J Hypertens. 2018 Jan 12;31(2):212-219. doi: 10.1093/ajh/hpx156.
Left ventricular (LV) diastolic dysfunction characterizes heart failure with a preserved ejection fraction. Although it is recognized that the renin-angiotensin-aldosterone system (RAAS) decreases LV diastolic function, whether systemic angiotensinogen (AGT) contributes to these effects is uncertain. Hence, the aim was to determine the relationship between systemic AGT concentrations and LV diastolic function.
LV diastolic function was determined from the mean of the lateral and septal wall myocardial tissue lengthening at the mitral annulus (average e') and from the ratio of early transmitral blood flow velocity (E) to average e' (E/e') in 445 Black African participants from a community sample.
In multivariate regression models with adjustments for age, sex, waist circumference diabetes mellitus, alcohol and tobacco use, hypertension treatment, systolic blood pressure (BP), and relative wall thickness, the square root of serum AGT concentrations was independently associated with E/e' (partial r (95% confidence interval [CI]) = 0.11 (0.02-0.21), P = 0.04), but not with average e' (partial r (95% CI) = -0.06 (-0.15 to 0.04), P = 0.25). There was no association between plasma renin concentrations and markers of diastolic function (all P > 0.05).
Circulating AGT concentrations are associated with LV diastolic function beyond BP and other confounders in an African population. Hence, through circulating AGT, the systemic RAAS may play an important role in contributing to LV diastolic function in Black Africans.
左心室(LV)舒张功能障碍是射血分数保留型心力衰竭的特征。尽管人们认识到肾素-血管紧张素-醛固酮系统(RAAS)降低了 LV 舒张功能,但全身血管紧张素原(AGT)是否有助于这些作用尚不确定。因此,本研究旨在确定全身 AGT 浓度与 LV 舒张功能之间的关系。
在来自社区样本的 445 名黑种人参与者中,通过测量二尖瓣环处侧壁和间隔壁心肌组织的平均伸长率(平均 e')以及早期二尖瓣血流速度(E)与平均 e'的比值(E/e')来确定 LV 舒张功能。
在调整年龄、性别、腰围、糖尿病、饮酒和吸烟、高血压治疗、收缩压(BP)和相对壁厚度的多元回归模型中,血清 AGT 浓度的平方根与 E/e'独立相关(部分 r(95%置信区间 [CI])= 0.11(0.02-0.21),P = 0.04),但与平均 e'无关(部分 r(95% CI)=-0.06(-0.15 至 0.04),P = 0.25)。血浆肾素浓度与舒张功能标志物之间没有关联(所有 P > 0.05)。
在非洲人群中,循环 AGT 浓度与 BP 和其他混杂因素以外的 LV 舒张功能相关。因此,通过循环 AGT,全身 RAAS 可能在导致黑种人 LV 舒张功能障碍方面发挥重要作用。