[Brain natriuretic peptide in patients with ST segment elevation myocardial infarction. Prognostic significance]

To study changes in the level of brain natriuretic peptide (BNP) in patients with ST segment elevation myocardial infarction (MI) to assess prognostic value of this marker and validity of its use as a criterion of therapy effects.

The trial enrolled 217 patients (102 males and 15 females, mean age 63.96 +/- 0.73 years) admitted to hospital on MI day 1. Plasmic level of BNP (Nt-proBNP) was measured 1, 7, 21 days, 8 weeks and 6 months after MI.

The severity of chronic cardiac failure (CCF) correlated with peptide content in the blood: it was by 46.6% higher in patients with chronic heart failure (CHF) functional class (FC) IV than in those with CHF FC I (p = 0.047), in FC III by 27.5% higher (p = 0.003) and in FCII--by 13.1% (p = 0.485). Initially high levels of BNP correlated with early development of CHF (R2 = 0.9058), with hospital lethality (in the deceased--1040.0 +/- 65.8 fmol/ml, in the survivors--461.4 +/- 26.2 fmol/ml, r = 0.35, p < 0.001) and overall lethality. A more pronounced decrease in the peptide level was seen in patients after 3 week intake of beta-adrenoblocker esmolol than in those who did not take it (by 125.2 vs 74.1 fmol/ml, respectively, p < 0.05). By BNP level, efficacy of perindopril vs captopris was studied (group 1 and group 2, respectively), in patients with ejection fraction under 40%. Initially, BNP levels were elevated and did not differ among the groups. On MI week 8 there was a decrease in the level of BNP by 25.4% (p = 0.004), 19.1% (p = 0.06) in groups 1 and 2, respectively. Six months after MI patients of group 1 had normal levels of BNP (up to 269.6 +/- 18.3 fmol/l).

Measurements of BNP levels are useful for prediction of poor prognosis in MI patients and evaluating efficacy of the treatment.