Abstract 11696: Cardiac Production of B-type Natriuretic Peptide Correlates Inversely with Body Mass Index: Involvement of Lipid Metabolism
Background: B-type natriuretic peptide (BNP) is produced from the heart in proportion to the severity of heart failure. Fatty acids (FAs) are the major substrates for cardiac energy production but their contribution decreases gradually as heart failure develops. Up until now, the mechanism which elucidates the relationship between obesity and low plasma levels of BNP has been unknown. We hypothesized that there may be a close relationship between BNP production and FAs metabolism.
Object: We examined the relationship between cardiac BNP production and FAs metabolism.
Methods: Seventy patients (average age, 62.4±11.6 yrs., 46 males and 24 females, average body mass index (BMI), 24.5±3.8kg/m2) who underwent cardiac catheterization were the subjects of this study. Blood samplings were done at the aortic root (AO) and coronary sinus (CS) for BNP and free FAs (FFAs) together with hemodynamic parameter measurement. Peripheral blood samplings for lipids and glucose were also performed.
Results: BMI had a significant positive correlation with both FFAs (AO) and triglyceride (TG) (r=0.526, P <0.0001 and r=0.389, P =0.0009, respectively). There was a significant positive correlation with FFAs (AO) and triglyceride (r=0.739, P <0.0001). BMI, FFAs(AO), TG and left ventricular ejection fraction (LVEF) had significant correlations with logBNP(AO) (r=-0.493, P<0.0001, r=-0.499, P <0.0001, r=-0.386, P =0.0011, and r=-0.500, P <0.0001, respectively), and with logBNPΔ(CS-AO); log(cardiac BNP production) (r=-0.491, P <0.0001, r=-0.582, P <0.0001, r=-0.347, P =0.0035, and r=-0.517, P <0.0001, respectively). There was also a significant negative correlation between FFAsΔ(AO-CS); cardiac FFAs uptake and logBNPΔ(CS-AO) (r=- 0.259, P =0.0305). Thus, BMI, FFAs (AO), TG, cardiac FFAs uptake, as well as LVEF, inversely correlated with cardiac BNP production. Multiple regression analysis, including plasma lipids, glucose and hemodynamic parameters, revealed that FFAs (AO) (P =0.0002) and LVEF (P =0.0003) were independent predictors of logBNPΔ(CS-AO) or cardiac BNP production.
Conclusion: We conclude that cardiac BNP production is inversely correlated with BMI, as well as LVEF, through the cardiac FAs metabolism.
- © 2011 by American Heart Association, Inc.