Prognostic value of N-terminal pro-form B-type natriuretic peptide (NT-proBNP) in patients with congenital heart disease undergoing cardiac surgery: a systematic review and meta-analysis of cohort studies

BACKGROUND: To perform an updated and comprehensive meta-analysis on the prognostic value of N-terminal pro-form B-type natriuretic peptide (NT-proBNP) in patients with congenital heart disease (CHD) undergoing cardiac surgery. METHODS: A systematic search was conducted until September 2021 for relevant studies published in PubMed, Web of Science Database and Embase. Based on the average values, NT-proBNP concentrations were classified as high and low levels. The outcomes of interest were mortality, cardiovascular events, and other postoperative outcomes. A random-effects model was used to calculate composite risk estimates and corresponding 95% confidence intervals (CIs). Possible sources of heterogeneity and stability of results were analyzed using subgroup and sensitivity analyses. RESULTS: A total of 32 studies published between 2008 and 2021 involving 7,571 participants were included. Results showed CHD patients at high NT-proBNP levels yielded an increased risk of mortality [risk ratio (RR) =1.14; 95% CI: 1.08–1.20] and cardiovascular events (RR =2.02; 95% CI: 1.26–3.24) compared with those at low NT-proBNP levels. No significant association was found between NT-proBNP and risks for other postoperative outcomes in CHD patients undergoing cardiac surgery (RR =1.73; 95% CI: 0.86–3.47). Significant heterogeneity was detected across studies regarding these risk estimates. Subgroup analysis found heterogeneity in the risk estimate of mortality was explained by geographic region, type of CHD, and assay method of NT-proBNP. Sensitivity analysis supported the robustness of results. CONCLUSIONS: Compared with CHD patients at low NT-proBNP levels, CHD patients at high NT-proBNP levels had elevated risks of mortality and cardiovascular events. Further large-scale and well-controlled studies are needed to confirm our findings.