Different patterns of NT-proBNP secretion in acute coronary syndromes

Background: The wide variability of NT-proBNP levels in acute coronary syndromes could arise from sympathetic activation and glomerular impairment. The aim of the study was to investigate, in this setting, the dependence of NT-proBNP from Chromogranin A (CgA) and Cystatin C (CC) levels, respectively assessing sympathetic activation and glomerular impairment. Methods: In 132 patients, 90 ST elevation acute coronary syndrome (STE-ACS) and 42 non ST elevation acute coronary syndrome (NSTE-ACS), within 24 h from symptoms and with creatinine levels lower than 141.4 mu mol/L, we measured NT-proBNP, CgA and CC levels. In 41 STE-ACS patients we evaluated the kinetic profiles of the markers. Results: From the multiple regression model, to investigate the dependence of NT-proBNP from CgA, CC levels, time from symptom STE-ACS/NSTE-ACS subsets, gender, adjusting for the effect of left ventricular ejection fraction and age we had evidence of. 1) interactions involving the subsets, the first with CgA levels and the second with age; 2) non linear increasing effect of the delay on NT-proBNP secretion. Conclusions: Our data showed that, in the population studied, sympathetic activation and age could affect NT-proBNP secretion yielding different secretory patterns in STE- or NSTE-ACS. Only for STE-ACS we observed higher marker secretion in older patients. (c) 2009 Elsevier B.V. All rights reserved.