RESUMO
Introduction: To investigate the relationship between cystatin C and cardiac dysfunction severity in patients with systolic heart failure. Methods: We recruited 100 hospitalized patients with systolic heart failure and 100 age-gender-matched controls. The clinical information of each patient was collected. Blood pressure, heart rate, height, and weight were measured, as were serum concentrations of cholesterol, renal function indices, cystatin C, and B-type natriuretic peptide (BNP). Transthoracic echocardiography was performed on each patient. Results: Cystatin C and other indices of renal function, such as urea nitrogen, creatinine, and uric acid, were significantly elevated in the serum of patients with heart failure and those with more severe cardiac dysfunction. The stepwise regression analyses showed that cystatin C was positively associated with BNP (ß = 0.18, P = 0.04, 95% CI: 21.1 ~ 1420.4) and left atrial diameter (LAD) (ß = 0.19, P = 0.04, 95% CI: 0.03 ~ 9.21) and was negatively associated with ejection fraction (ß = -0.22, P = 0.023, 95% CI: -12.4 ~ -0.93), while creatinine was only positively correlated with BNP (ß = 0.23, P = 0.03, 95% CI: 1.11 ~ 20.7). The Receiver Operating Characteristic (ROC) curves demonstrated significantly more severe cardiac dysfunction (NYHA III/IV) in patients with cystatin C ≥ 0.895mg/L (sensitivity was 83.0%, specificity was 80.9%, AUC = 0.893) and creatinine ≥ 91.5µmol/L (sensitivity was 71.7%, specificity was 70.2%, AUC = 0.764). Conclusion: Cystatin C was significantly correlated with cardiac structure and function in patients with systolic heart failure, and it was more valuable than creatinine to evaluate the severity of heart failure.