Serial assessment of brain natriuretic peptide in single ventricle patients with a hybrid stage 1 palliation

Abstract

Brain natriuretic peptide (BNP) has been used as a marker for heart failure. Cross-sectional studies have documented differences in BNP levels in patients with single ventricle physiology but the utility of longitudinal samples has not been established. We hypothesized that change in BNP would correlate with change in clinical status in single ventricle patients palliated with a hybrid stage 1 palliation. Retrospective Ross heart failure score, inotrope score, lactate, and creatinine were obtained at time of each BNP. Events requiring CPR or intubation were noted in relationship to BNP. Data was analyzed with non-parametric statistics with p<0.05 considered significant.14 patients (11 with serial values) had BNP values obtained primarily in the inpatient setting between 9/2010 and 9/2012. BNP values were obtained at a median age of 38days (range 1–170days) in patients with hypoplastic left heart palliated with a hybrid palliation. There was no correlation between BNP and inotrope score, age at time of BNP or systemic saturation. BNP correlated with lactate (p=0.002, r2=0.12) and Ross score (p<0.0001, r2=0.25). BNP values were greater in patients with an elevated lactate (median 3980pg/ml, range 565–4500 vs. 1213pg/ml, range 94–4500, p=0.0003) or if related to an arrest or intubation (median 4500pg/ml, 364–4500 vs. 1536pg/ml, 94–4500, p<0.0001). A change in BNP value was associated with a change in Ross score (p<0.0001, r2=0.19).We conclude that serial measurements of BNP values may help to predict worsening heart failure in infants with single ventricle physiology palliated by a hybrid stage 1 procedure.