Zdravniški Vestnik (Nov 2007)
N-terminal natriuretic propeptide type-b (NT-proBNP) and left ventricular ejection fraction in acute phase of st-segment elevation myocardial infarction and 1-year later
Abstract
Background: N-terminal natriuretic propeptide type-B (NT-proBNP) is a newer biochemical marker in acute coronary syndrome. NT-proBNP concentration of acute and chronic phase of STsegment elevation myocardial infarction is a predictor of ventricular function and prognosis.Methods: In a sequence of 35 patients (22 men, 13 women, mean age 66.4 ± 9.6 years) with first STEMI an NT-proBNP plasma concentration and echocardiography was performed in acute phase and one year later. A comparison of NT-proBNP values of both phases was done. In addition, a correlation among NT-proBNP, ejection fraction (EF) and E/Em ratio was analysed.Results: NT-proBNP concentration measured in STEMI acute phase was significantly higher in comparison with the value measured one year later (1833 pg/ml:419 pg/ml, p < 0.001). NT-proBNP was significantly higher in patients with anterior STEMI (n = 15) compared with the patients with inferior STEMI (n = 20) in acute phase and one year later. In patients with inferior STEMI a mean NT-proBNP value one year after infarction was below the limit values of 300 pg/ml (236 pg/ml). Between EF values in acute phase and one year later there was no significant difference (p = 0.667). 9 patients (26 %) had EF lower than 50 %. EF was significantly lower with anterior STEMI than with inferior one (p < 0.001). E/Em ratio betwen 2 groups showed no significant difference. A correlation between whole group NT-proBNP and ET was statistically insignificant and negative in STEMI acute phase (r = –0.526, p < 0.001) and one year later (r = –0.495, p < 0.003). Between NTproBNP and E/Em ratios no statistically significant difference was found. In subgroup of patients having E/Em ratio at one year greater than 10, NT-proBNP concentration was significantly higher in comparison with patients having E/Em lower than 10 (p < 0.001). A group of 8 patients with 3-vessel coronary artery disease (CAD) had significantly higher NT-proBNP one year after STEMI than a group of 15 patients with 1-vessel CAD (p < 0.001). EF values in both groups did not differ significantly.Conclusions: A significant negative correlation between NT-proBNP and EF was proved. NT-proBNP concentrations in acute phase and one year later in patients with anterior STEMI were significantly higher from the ones in patients with inferior STEMI. One year after STEMI patients with 3-vessel coronary artery disease had a significantly higher NT-proBNP than patients with 1-vessel CAD. Increase ratio of NT-proBNP and coronarographic and echocardiographic data help in detection of patients with greater complication possibilities. For these patients, intense treatment, more accurate monitoring and more frequent follow-ups should be envisaged.
