[The importance of NGAL and cystatin C biomarkers in cardiovascular diseases].

Cystatin C is an inhibitor of lysosomal proteases and extracellular cysteine protease, it participates in the regulation of metabolism of extracellular proteins. It is fully glomerular filterable, completely absorbed and catabolised in proximal tubule cells. NGAL (neutrophil gelatinase-associated lipocalin) is an acute phase protein, participating in antibacterial immunity and his important feature is the formation of complex with metalloproteinase 9 (MMP-9), thereby increasing its activity and prevents its degradation. NGAL is freely filtered across the glomerular membrane and is reabsorbed by endocytosis in the proximal tubule. NGAL detected in urine is produced mainly in the distal nephron. The serum cystatin C and NGAL can diagnose acute renal impairment one or two days earlier in the comparison with the monitoring of renal function by serum creatinine. Moreover, compared with the information provided by creatinine or by estimated GFR, the elevated cystatin C gives, in patients with cardiovascular disease, information about worse prognosis. Increased level of NGAL was detected in patients with acute myocardial infarction, heart failure or stroke. There is a lack of data about the prognostic significance of NGAL in patients after myocardial infarction or heart failure, no data about their comparison or interaction with natriuretic peptides exists up today.