Brain natriuretic peptide: A marker of myocardial dysfunction and prognosis during severe sepsis.

Objective: To investigate the value of brain natriuretic peptide plasma levels as a marker of systolic myocardial dysfunction during severe sepsis and septic shock.
Design: Prospective observational study.
Setting: Intensive care unit.
Patients: A total of 34 consecutive patients with severe sepsis (nine patients) or septic shock (25 patients) without previous cardiac, respiratory, or chronic renal failure.
Interventions: None.
Measurements and Main Results: Myocardial systolic performance was assessed by fractional area contraction (FAC) using echocardiography performed on days 2 (FACD2) and 8. Plasma levels of brain natriuretic peptide were measured at days 1-4 and 8 after the beginning of severe sepsis. Among 34 patients (Simplified Acute Physiology Score II, 43 +/- 2.5), 15 (44%) presented with initial myocardial dysfunction (FACD2 < 50%). Lungs were the origin of sepsis in 65% of patients. The 28-day mortality was 29%. Comparisons were performed between patients with (FACD2 < 50%) and without (FACD2 > or = 50%) myocardial dysfunction. Plasma levels of brain natriuretic peptide were significantly higher in patients with FACD2 < 50% than in those with FACD2 > or = 50% (p <.05) from day 2 to day 4. Brain natriuretic peptide levels were also significantly higher on days 2 and 3 in patients who died during their intensive care unit stay (p <.05).
Conclusions: Systolic myocardial dysfunction is present in 44% of patient with severe sepsis or septic shock. In this setting, brain natriuretic peptide seems useful to detect myocardial dysfunction, and high plasma levels appear to be associated with poor outcome of sepsis, but further studies are needed.