Combination of B-type brain natriuretic peptide with left ventricular diastolic dysfunction for prediction of mortality in the patients with septic shock

Abstract

To evaluate the prognostic value of combination of plasma brain natriuretic peptide(BNP) with the ratio of early diastolic mitral inflow velocity to early diastolic mitral annulus velocity(E/E') in the patients with septic shock. From June 2012 to December 2013 , 127 patients with septic shock were consecutively recruited and underwent trans-thoracic echocardiography examination within 6 h after admission to Intensive Care Unit(ICU), Zhejiang Provincial People's Hospital. Plasma BNP concentration was measured using ELISA method. All Clinical, laboratory, and survival data were prospectively collected. Of 127 patients enrolled, mean values for age were(59.9±17.3) years and APACHE Ⅱ score(16.8±5.8), respectively. 95 patients(74.8%) took mechanical ventilation. 28- , 60-day mortality rate was 36.3% and 42.3%, respectively. Univariate Cox regression analysis showed that age, coronary artery disease, serum creatinine and lactate, plasma BNP, left ventricular ejection fraction(LVEF), E/E' and APACHE Ⅱ score were significantly(P≤0.05) associated with 60-day mortality. Multivariate analysis revealed that serum lactate, plasma BNP(χ(2)=9.4, P=0.002) , E/E'(χ(2)=4.89, P=0.02) and APACHE Ⅱ score(χ(2)=10.6, P=0.001) remained independent predictors for 60-day mortality. ROC curve analysis showed that the optimal plasma BNP and E/E' cutoff values identified were 338.8 pg/ml and 10.8, and the areas under ROC curve were 0.89(sensitivity: 83.7%; specificity: 81.4%)and 0.83(sensitivity: 76.7%; specificity: 72.9%)for 60-day mortality, respectively. In addition to plasma BNP and clinical predictors, the E/E' could provide in independent and incremental prognostic value of 60-day mortality(χ(2)=59.3 vs 47.8, P<0.001). Plasma BNP and E/E' are independent predictors for 60-day mortality, and combination of plasma BNP and E/E' could improve risk stratification in patients with septic shock.