The effects of continuous positive airway pressure on plasma brain natriuretic peptide concentrations in patients presenting with acute cardiogenic pulmonary edema with preserved left ventricular systolic function.

Background: It has been established that plasma brain natriuretic peptide (BNP) concentrations in patients with acute cardiogenic pulmonary edema (ACPE) increase in proportion to heart failure.

Objectives: The aim of this study is to assess the effects of continuous positive airway pressure (CPAP) treatment on plasma BNP concentrations in patients presenting with ACPE with preserved left ventricular (LV) systolic function.

Methods: This was a prospective, observational single-center study in the emergency unit of Valduce Hospital. Twelve patients (group A) presenting with ACPE and preserved LV ejection fraction and 14 patients (group B) with systolic heart dysfunction (LV ejection fraction <45%) underwent CPAP (10 cm H(2)O) through a face mask and standard medical therapy. Plasma BNP concentrations were collected immediately before CPAP and 3, 6, and 24 hours after treatment. All patients underwent a morphological echocardiographic investigation shortly before CPAP.

Results: Three hours after admission, BNP significantly decreased in patients with ACPE and preserved LVEF (from 998 + or - 467 pg/mL to 858 + or - 420 pg/mL; P < .05), whereas in those with systolic dysfunction, BNP was higher than during baseline (from 1352 + or - 473 pg/mL to 1570 + or - 595 pg/mL; P < .05).

Conclusions: The preliminary results of the present study show that CPAP, after 3 hours, lowers BNP levels in patients with ACPE and preserved LV systolic function compared with patients affected by systolic ACPE dysfunction where BNP levels do not change significantly.