The relationship between amniotic fluid levels of brain-type natriuretic peptide and recipient cardiomyopathy in twin–twin transfusion syndrome

Objective We sought to evaluate amniotic fluid brain natriuretic peptide (BNP) levels as a biomarker of recipient twin (RT) cardiomyopathy (RTCM) in twin-twin transfusion syndrome. Study Design Amniotic fluid samples were obtained from 157 twin-twin transfusion syndrome RTs and from 6 singletons (controls) from 2007 through 2009. N-terminal prohormone BNP (NT-proBNP) levels were quantified by enzyme-linked immunosorbent assay. RTCM was classified as mild (IIIA), moderate (IIIB), or severe (IIIC) by fetal echocardiography. The relationship between NT-proBNP and RTCM was evaluated using analysis of variance. The ability of NT-proBNP to predict moderate or greater RTCM was evaluated by receiver operating characteristic analysis. Results There is a significant positive correlation between NT-proBNP levels and worsening RTCM (r = 0.33; P Conclusion This is the first large case series that demonstrates a relationship between NT-proBNP and RTCM. This pathophysiologic insight supports ongoing efforts to develop screening biomarkers.