Apelin and Cardiac Function in Hemodialyzed Patients: Possible Relations?

BACKGROUND: Apelin, a newly discovered adipocytokine, is produced by white adipose tissue and is also expressed in the kidney and heart. Increasing evidence suggests a role for apelin in the pathology of the cardiovascular system. Cardiovascular disease is a major contributor to the mortality and morbidity in patients with chronic renal failure. The aim of this study was to assess associations between apelin, coronary artery disease (CAD) and echocardiographic parameters in hemodialyzed patients. PATIENTS AND METHODS: We investigated plasma apelin levels (using commercially available kits) in 81 nondiabetic, clinically stable hemodialyzed patients (38 females, 43 males) with and without CAD. RESULTS: Patients with CAD were significantly older, with significantly increased left ventricular internal end-diastolic dimension (LVIDd), left ventricular internal end-systolic dimension (LVISd), right ventricle (RV), left atrium (LA), interventricular septum in diastole, left ventricle posterior wall in diastole (LVPW), aorta, pulmonary artery, significantly lower ejection fraction and apelin than patients without CAD. We observed statistically significant correlations between apelin and echocardiographic parameters: LVIDd, LVISd, RV, LA, right atrium, LVPW, aorta, and serum lipids: cholesterol, LDL, triglycerides. In multiple logistic regression analysis, the only associate of apelin was LVIDd. CONCLUSIONS: Apelin level was significantly lower in dialyzed patients with CAD and it was associated with cardiac function. Apelin might be involved in the pathophysiology of cardiovascular disease in chronic renal failure. Since apelin is an inotrope in normal and failing hearts, this finding may have clinical implications for future use of apelin as a novel inotropic agent also for patients with uremic cardiomyopathy.