Aminoterminal pro-B-type natriuretic peptide: heart or lung disease in the neonate?.

OBJECTIVES: B-type natriuretic peptides have been shown to enable differentiation between heart and lung diseases in adults and children. In neonates, the role of natriuretic peptides for diagnosis of congenital heart defect (CHD) is not yet ascertained. The purpose of this single-center prospective study was to investigate aminoterminal B-type natriuretic peptide concentrations and their time courses during the first 5 days of life in neonates with CHD compared with neonates with respiratory distress. DESIGN: Single-center prospective study. SETTING: Tertiary-care neonatal ICU. PATIENTS: Aminoterminal B-type natriuretic peptide levels of 40 neonates with arterial duct-dependent CHD and of 40 neonates with respiratory distress without CHD were analyzed on the first, second, third, and fifth day of life. MAIN RESULTS: Mean aminoterminal B-type natriuretic peptide concentrations in the CHD group were significantly higher on the second (14191 vs. 4872 pg/mL), third (17790 vs. 3524 pg/mL), and fifth day (17015 vs. 4044 pg/mL), but not on the first day of life. Repeated measurements analysis of variance revealed a significantly different time course of aminoterminal B-type natriuretic peptide concentrations between the two groups. CONCLUSIONS: On the first day of life, aminoterminal B-type natriuretic peptide cannot differentiate between CHD and respiratory distress without CHD in the neonate. From the second day onwards, aminoterminal B-type natriuretic peptide in neonates with CHD shows higher values and a different time course and enables differentiation between CHD and respiratory distress due to other than cardiac reasons.

Amino terminal pro B-type natriuretic peptide levels are elevated in the cord blood of neonates with congenital heart defect.

This prospective study investigates whether amino terminal proB-type natriuretic peptide (NT-proBNP) levels are elevated in neonates with congenital heart defect (CHD). NT-proBNP levels in the umbilical cord blood of 60 neonates with prenatally diagnosed CHD, in the cord blood of 200 control subjects, and in the plasma of the respective mothers were analyzed using an automated enzyme immunoassay. NT-proBNP concentrations in the cord blood of the CHD group were significantly elevated compared with controls [median (range): 158 pg/mL (378-3631 pg/mL) and 626 pg/mL (153-2518 pg/mL); p value <0.001]. The NT-proBNP concentrations of the newborns and their mothers did correlate neither in the CHD nor in the control group. In 54 patients with CHD, NT-proBNP levels were measured on the median 5th day of life. They showed a significant increase (median 1665 pg/mL and 19222 pg/mL; p < 0.001). NT-proBNP levels in the cord blood of neonates with CHD are significantly elevated and show a marked increase in the first week of life. Furthermore, this study confirms previously published reference intervals of NT-proBNP in the cord blood of healthy neonates as well as the finding that there is no exchange of NT-proBNP across the placenta.

Open-heart surgery in premature and low-birth-weight infants--a single-centre experience.

OBJECTIVE: Because of their poor clinical status, infants may require surgery for congenital heart disease regardless of weight or prematurity. This retrospective review describes a single-centre experience with open-heart surgery in low-weight infants. METHODS: From November 1997 to December 2006, 411 open-heart surgery procedures were performed in neonates. This included 46 consecutive infants weighing less than 2500 g, who underwent cardiopulmonary bypass for correction of congenital heart defects (n=34) or Norwood stage I palliation of hypoplastic left heart syndrome (HLHS) (n=12). In the low-weight group were 23 males and 23 females with a median age of 10 days and a median weight of 2.26 kg (range: 1.28-2.49 kg). RESULTS: Early mortality was 8.2% in patients weighing more than 2.5 kg and 13% in the low-weight group. Within the low-weight group, weight at surgery, history of prematurity and prevalence of additional extracardiac malformations did not influence early mortality. At a median follow-up time of 32 months overall mortality was 21%. Thirty-four patients had a neurological follow-up examination 30 months postoperatively. Of the 34 survivors, 11 showed neurological deficits. CONCLUSIONS: In our patient population, early mortality was higher for infants weighing less than 2.5 kg. However, within the low-weight group, lower weight at surgery or history of prematurity was not associated with a higher mortality or bad neurological outcome.