Heart failure biomarkers in patients with dilated cardiomyopathy.
BACKGROUND
We set out to evaluate the utility of selected heart failure (HF) biomarkers in patients with dilated cardiomyopathy (DCM).


METHODS
In a prospective, randomized study, 68 DCM patients with left ventricular ejection fraction (LVEF) ≤ 40% treated optimally were included. They were observed for 5 years. Initial and control tests included full clinical examination, measurement of tumor necrosis factor alpha (TNF-α), interleukin 6 (IL-6) and IL-10, syndecan-4, cystatin C (CysC) and N-terminal pro-brain natriuretic peptide (NT-proBNP), echocardiographic examination, and the assessment of exercise capacity in 6-minute walk test (6MWT).


RESULTS
Finally, after 5-year follow-up we analyzed the data of 45 DCM patients. Concentration of syndecan-4 correlated negatively with LVEF (R=-0.36, p=0.02) and positively with LV systolic (R=0.57, p<0.001) and diastolic diameters (R=0.64, p<0.001). A positive correlation between CysC and right ventricular diastolic diameter (R=0.38, p=0.01), and negative correlations between CysC and glomerular filtration rate (R=-0.49, p<0.001), LVEF (R=-0.4, p=0.02), and 6 MWT (R=-0.46, p<0.001) were noted. Patients who had an increase in LVEF during 5 years were characterized by lower levels of CysC (p=0.01) and NT-proBNP (p<0.001). CysC≤95mg/l and NT-proBNP≤32pg/ml were the best predictors of LVEF increase in DCM patients. Multivariate regression analysis showed that 6 MWT was the only independent predictor of HF re-hospitalization (OR 0.989; p<0.001), and NT-proBNP and LV diastolic diameter were the only risk factors of increased mortality (OR 1.001; p=0.007 and OR 2.960; p=0.025, respectively) in DCM patients.


CONCLUSIONS
CysC correlates negatively with both kidney function and exercise capacity. Syndecan-4 may be a useful biomarker for predicting adverse LV remodeling in DCM patients.