Association of free fatty acid binding protein with central aortic stiffness, myocardial dysfunction and preserved ejection fraction heart failure

There is an established link between cardiometabolic abnormality, central arterial stiffness, and preserved ejection fraction heart failure (HFpEF). Adipocyte free fatty acid binding protein (a-FABP) has been shown to signal endothelial dysfunction through fatty acid toxicity, though its role in mediating ventricular-arterial dysfunction remains unclear. We prospectively examined the associations of a-FABP with central arterial pressure using non-invasive applanation tonometry (SphygmoCor) and cardiac structure/function (i.e., tissue Doppler imaging [TDI] and global longitudinal myocardial strain [GLS]) in patients with cardiometabolic (CM) risk (n = 150) and HFpEF (n = 50), with healthy volunteers (n = 49) serving as a control. We observed a graded increase of a-FABP across the healthy controls, CM individuals, and HFpEF groups (all paired p < 0.05). Higher a-FABP was independently associated with higher central systolic and diastolic blood pressures (CSP/CPP), increased arterial augmentation index (Aix), lower early myocardial relaxation velocity (TDI-e '), higher left ventricle (LV) filling (E/TDI-e ') and worsened GLS (all p < 0.05). During a median of 3.85 years (interquartile range: 3.68-4.62 years) follow-up, higher a-FABP (cutoff: 24 ng/mL, adjusted hazard ratio: 1.01, 95% confidence interval: 1.001-1.02, p = 0.04) but not brain natriuretic peptide, and higher central hemodynamic indices were related to the incidence of heart failure (HF) in fully adjusted Cox models. Furthermore, a-FABP improved the HF risk classification over central hemodynamic information. We found a mechanistic pathophysiological link between a-FABP, central arterial stiffness, and myocardial dysfunction. In a population with a high metabolic risk, higher a-FABP accompanied by worsened ventricular-arterial coupling may confer more unfavorable outcomes in HFpEF.