Donor B-type natriuretic peptide predicts early cardiac performance after heart transplantation

Abstract

Background: Decision processes in heart donation remain difficult and are often based on subjective evaluation. We measured B-type natriuretic peptide (BNP) in heart donors and analyzed its value as a discriminator for early post-transplant cardiac performance.

Methods: Blood samples were prospectively obtained in 94 brain-dead patients, among whom 56 were scheduled for heart donation. BNP values were not available prior to donor selection. BNP of heart donors was related to invasively measured cardiac output and hemodynamic parameters, early after transplantation.

Results: BNP, expressed as median (interquartile range), was 65 (32 to 149) pg/ml in brain-dead donors scheduled for heart donation. BNP was higher (287 pg/ml, range 65 to 457; p = 0.0001) in donors considered ineligible for heart donation. In 45 heart recipients, cardiac output (CO) of 5.6 (4.8 to 6.2) liters/min was measured at Day 12 (10-15). In the univariate analysis, recipient CO correlated significantly with donor BNP (r = -0.34, p = 0.025). Stepwise multiple regression, including donor variables such as body mass index, age, BNP, norepinephrine dose, gender and total ischemic time, identified donor BNP and age as the best independent predictors of CO in recipients (p = 0.02 and p = 0.005, respectively, R(2) of the model = 0.27). Donor BNP of >160 pg/ml had 89% accuracy to predict poor cardiac performance in the recipient (cardiac index <2.2 liters/min/m(2)). High donor BNP was independently correlated with a longer hospital stay.

Conclusions: Donor BNP was found to be related to cardiac performance, early after cardiac transplantation. BNP measurement in heart donors could become a useful tool in the evaluation of donor hearts.