Document Detail


Impact of aldosterone on left ventricular structure and function in young normotensive and mildly hypertensive subjects.
MedLine Citation:
PMID:  10802001     Owner:  NLM     Status:  MEDLINE    
Abstract/OtherAbstract:
Left ventricular (LV) hypertrophy is an independent risk factor for cardiovascular morbidity and mortality. Experimental data revealed that elevated circulating aldosterone is associated with increased collagen accumulation resulting in myocardial fibrosis. To analyze whether aldosterone is also associated with cardiac structural and functional changes in humans, we examined the effects of aldosterone on LV structure and function before and after suppression of aldosterone by increasing oral salt intake. The study group comprised 26 normotensive male white healthy control subjects (age 26 +/- 3 years) and 31 male white subjects (age 25 +/- 3 years) with mild essential hypertension (World Health Organization stages I to II). Two-dimensional-guided M-mode echocardiography and 24-hour ambulatory blood pressure (BP) monitoring was performed in each subject. Simultaneously, we measured 24-hour urinary sodium excretion, 24-hour urinary aldosterone, and serum aldosterone concentration at baseline and after increasing oral salt intake to suppress aldosterone secretion. In all subjects LV mass correlated with body mass index (r = 0.42, p <0.001) and both 24-hour ambulatory systolic (r = 0.28, p <0.05) and diastolic (r = 0.25, p <0.05) BP. Changes in urinary sodium excretion correlated inversely with changes in serum aldosterone concentration (r = -0.28; p <0.05). Urinary aldosterone concentration after salt loading decreased in normotensive (10.98 vs 7.44 microg/24 hours; p <0.02) but not in hypertensive (9.34 vs 10.51 microg/24 hours; p = NS) subjects. Serum and urinary aldosterone levels at baseline were not related to LV structure or function. In contrast, after increasing oral salt intake, urinary aldosterone concentration was related to LV mass (r = 0.43; p <0.01) and impaired midwall fractional fiber shortening (r = -0.33; p <0.02) in all subjects, independent of 24-hour ambulatory BP. Subgroup analysis revealed that this was significant only in hypertensive (r = 0.46; p <0.01 and r = -0.44; p <0.02, respectively) but not in normotensive (r = 0.28 and -0.16; p = NS for both, respectively) subjects. Consistently, the greater serum aldosterone remained after increasing oral salt intake, the greater was LV mass (r = 0.35; p <0.01). The latter was found in hypertensive subjects (r = 0.44; p <0.02), independent of 24-hour ambulatory BP, but not in normotensive subjects (r = 0.025; p = NS). Inadequate suppression of aldosterone in response to an increase in oral salt intake is related to LV structural and functional changes in hypertensive subjects. Thus, our results support experimental data indicating that aldosterone affects LV structure and function in humans and that this effect is BP independent.
Authors:
M P Schlaich; H P Schobel; K Hilgers; R E Schmieder
Publication Detail:
Type:  Clinical Trial; Journal Article; Research Support, Non-U.S. Gov't    
Journal Detail:
Title:  The American journal of cardiology     Volume:  85     ISSN:  0002-9149     ISO Abbreviation:  Am. J. Cardiol.     Publication Date:  2000 May 
Date Detail:
Created Date:  2000-07-14     Completed Date:  2000-07-14     Revised Date:  2006-11-15    
Medline Journal Info:
Nlm Unique ID:  0207277     Medline TA:  Am J Cardiol     Country:  UNITED STATES    
Other Details:
Languages:  eng     Pagination:  1199-206     Citation Subset:  AIM; IM    
Affiliation:
Department of Medicine IV/Nephrology, University of Erlangen-Nürnberg, Nürnberg, Germany.
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms
Descriptor/Qualifier:
Adult
Aldosterone / blood,  physiology*,  urine
Blood Pressure / drug effects*
Blood Pressure Monitoring, Ambulatory
Humans
Hypertension / metabolism*
Male
Sodium Chloride / pharmacology*,  urine
Ventricular Function, Left / drug effects*,  physiology
Chemical
Reg. No./Substance:
52-39-1/Aldosterone; 7647-14-5/Sodium Chloride

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine


Previous Document:  Comparison of diagnostic accuracy of sublingual nitroglycerin test and low-dose isoproterenol test i...
Next Document:  Effect of spironolactone on ventricular arrhythmias in congestive heart failure secondary to idiopat...