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Systemic Angiotensinogen Concentrations Are Independently Associated With Left Ventricular Diastolic Function in a
Aletta M E Millen1, Angela J Woodiwiss1, Monica Gomes1
1Cardiovascular Pathophysiology and Genomics Research Unit, School of Physiology, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa.
American Journal of Hypertension
|October 7, 2017
Summary
Systemic angiotensinogen (AGT) concentrations are linked to left ventricular (LV) diastolic dysfunction in Black Africans. This suggests the renin-angiotensin-aldosterone system (RAAS) may influence heart function in this population.
Area of Science:
- Cardiology
- Renal Physiology
- Population Health
Background:
- Left ventricular (LV) diastolic dysfunction is a key feature of heart failure with preserved ejection fraction.
- The renin-angiotensin-aldosterone system (RAAS) is known to impair LV diastolic function.
- The specific role of systemic angiotensinogen (AGT) in this process remains unclear.
Purpose of the Study:
- To investigate the association between systemic AGT concentrations and LV diastolic function.
- To explore the potential contribution of systemic AGT to diastolic dysfunction in an African population.
Main Methods:
- LV diastolic function assessed using myocardial tissue Doppler imaging (average e') and mitral inflow velocity (E/e') in 445 Black African participants.
- Multivariate regression models adjusted for multiple demographic, clinical, and lifestyle factors.
Main Results:
- Serum AGT concentrations were independently associated with E/e' (P=0.04), a marker of diastolic dysfunction.
- No significant association was found between AGT and average e', nor between plasma renin and diastolic function markers.
- The association between AGT and E/e' persisted after adjusting for blood pressure and other confounders.
Conclusions:
- Circulating AGT levels are associated with LV diastolic function in a Black African population, independent of blood pressure.
- Systemic AGT, via the RAAS, may play a significant role in the development of LV diastolic dysfunction in this demographic.
- Further research is warranted to elucidate the precise mechanisms.
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