Neurohormones and Cytokines in Heart Failure. Correlation With Coronary Flow Reserve

Abstract

In heart failure, the coronary flow reserve (CFR) measured by positron-emission tomography (PET) is reduced. As neurohormone and cytokine levels are also altered in patients with the condition, our aim was to determine whether there is a correlation between CFR and neurohormone and cytokine levels. The study included 40 patients with heart failure but without ischemic heart disease. Myocardial blood flow was measured by PET using nitrogen-13 ammonia at baseline and during ATP infusion. The CFR was calculated for each patient. In addition, levels of the following were determined: norepinephrine, endothelin-1, angiotensin-II, atrial natriuretic peptide (ANP), brain natriuretic peptide (BNP), tumor necrosis factor-alpha, interleukin (IL)-1beta, soluble IL-2 receptor, and IL-6. All neurohormone levels were elevated above reference values. The levels of all cytokines, except IL-1beta, were also elevated. There was a significant negative correlation between CFR and the levels of several neurohormones: ANP (r=-0.476), BNP (r=-0.442), and IL-6 (r=-0.509). In heart failure, the decrease in CFR is correlated with increases in the levels of certain neurohormones (i.e., ANP and BNP) and cytokines (i.e., IL-6), with vasodilatory effect. These increases are probably are related to compensatory mechanisms that are unable to correct for the endothelial dysfunction present in these patients.