Clinical implication of blood levels of B-type natriuretic peptide in pediatric patients on mechanical circulatory support

Background B-type natriuretic peptide (BNP) is a marker of heart failure. In adult patients with heart failure, decreased BNP levels after implantation of ventricular assist devices may be indicative of recovery. However, BNP levels among pediatric patients receiving mechanical support are largely unknown. Methods Fifteen pediatric patients with cardiogenic shock who were supported by extracorporeal membrane oxygenation (ECMO) were evaluated. The BNP levels were determined before ECMO initiation, during ECMO support, and after ECMO removal. Results All patients had elevated BNP levels before initiation of ECMO (median, 1,430 pg/mL; range, 361 to 5,000 pg/mL). Among the 15 patients, 1 received heart transplantation. Extracorporeal membrane oxygenation was withdrawn in 2 patients, and the other 12 patients were weaned from ECMO. Four patients died after initially successful weaning from ECMO. The BNP levels of the nonsurvivors (median, 3,685 pg/mL; range, 2,494 to 5,000 pg/mL) were higher than those of the survivors (median, 1,127pg/mL; range, 108 to 3,030 pg/mL) on the next few days after ECMO removal ( p = 0.016). The BNP levels on the fourth day after removal of ECMO among the survivors (median, 498 pg/mL; range, 108 to 890 pg/mL) were lower than those among the nonsurvivors (median, 3,900 pg/mL; range, 3,230 to 5,000 pg/mL; p = 0.017). Conclusions Among pediatric patients supported with ECMO, the survivors had lower BNP levels than those who did not survive. We suggest that serial blood BNP levels can be potential markers for monitoring pediatric patients on mechanical circulatory support, and the concept merits further study.