Assessment of Serum Cystatin C Levels in Newly Diagnosed Acute Myocardial Infarction at the Onset and at the Time of Hospital Discharge

BACKGROUND Cystatin C (Cys-C) is a marker of renal damage. Higher serum levels of Cys-C were observed in cardiovascular disease. This study aimed to test the null hypothesis that Cys-C levels in newly diagnosed acute myocardial infarction (AMI) may remain high in the survival and the impact of the cardiometabolic risk factors is small. METHODS Forty patients with AMI are enrolled in this study. The cardiometabolic factors including the anthropometric measurements, blood pressure and lipid profile were determined. The diagnosis of AMI is based on the electrocardiograph, cardiac enzymes and positive troponin-c (cTn) test. Quantitative determination of serum high sensitive C-reactive protein (hs-CRP) and Cys-C was carried out, at the time of admission and at the time of the discharge, using the enzyme-linked immunosorbent assay (ELISA) technique. RESULTS Serum Cys-C levels significantly increased at the time of the admission (1,296 ± 431.8 ng/mL) and at the time of the discharge (1,244.6 ± 482 ng/mL) compared with the reference levels (0.7 ± 0.2 ng/mL) of the healthy subjects. Non-significant differences were found between Cys-C levels in respect to the presence or absence of the cardiometabolic risk factors at the times of admission and discharge. Significant decrease of Cys-C levels was found in patients who have negative cTn at the time of discharge compared with corresponding levels at the time of admission. CONCLUSIONS We conclude that AMI patients have significant high serum levels of Cys-C at the time of admission and the levels significantly decreased in patients with negative cTn test within few days indicating an association between infarct size and the levels of Cys-C.