Cystatin-C as a predictor for major adverse cardiac events in patients with acute coronary syndrome

Cystatin-C (CYS-C) has emerged as a highly sensitive marker of even a mildly impaired glomerular filtration rate. Experimental studies have suggested that its inhibitory effects on cysteine protease may help to prevent plaque destabilisation. We aimed to evaluate the predictive value of CYS-C level for major adverse cardiac events (MACE) including mortality and morbidity during the hospital stay and 3-month follow-up period. Methods: Seventy-five patients were hospitalised for acute coronary syndrome (ACS). Another control group consisted of patients who were presented with chest pain but no evidence of ischaemic heart disease documented by laboratory markers and angiography. Serum CYS-C levels were measured during the first 24 h of admission. Patients with an abnormal creatinine-derived glomerular filtration rate (GFR) were excluded. Coronary angiography was performed for the entire study population. Results: In group I, the mean CYS-C was 1.836 ± 0.782 mg/l vs. 0.991 ± 0.163 mg/l in the control group (P < 0.000). Cystatin-C showed a moderate correlation with total cholesterol in group I (r = 0.5) and with LDL (r = 0.367, P < 0.01). CYS-C showed a moderate positive correlation with the number of diseased vessels (r = 0.419, P < 0.01) and a moderate significant positive correlation with Killip classification (r = 0.349). Smoking was the only predictor associated with a high CYS-C level in the multivariate regression analysis (P = 0.033). CYS-C was an independent predictor of MACE and heart failure complications either in-hospital or during follow-up (P < 0.05). Conclusions: CYS-C could be a useful marker for diagnosing coronary arteriosclerosis. An elevated CYS-C in patients with ACS is an independent predictor of MACE either in-hospital or during follow-up