Bioactive Adrenomedullin (bio-ADM) as a Biomarker for Capillary Leak in Children with Congenital Heart Defects Undergoing Cardiac Surgery on Cardiopulmonary Bypass (CPB)

Background: Systemic inflammatory response is a common complication in children with congenital heart disease (CHD) undergoing cardiac surgery on cardiopulmonary bypass (CPB). It is associated with endothelial dysfunction, increased morbidity and mortality. Bioactive adrenomedullin (bio-ADM) is a vasoactive peptide regulating vascular tone and endothelial integrity. The aim of this study was to evaluate the dynamics of plasma bio-ADM levels in children undergoing open heart surgery and its possible role in the development of capillary leak syndrome.

Methods: This study included 73 pediatric patients with CHD undergoing open-heart surgery on CPB. Plasma samples for bio-ADM measurement were collected at five different time points in the pre-, intra-, and postoperative period. The primary endpoint of the study was a net increase in bio-ADM levels after surgery. Secondary endpoints included association of bio-ADM levels with clinical signs of capillary leak and vasoplegia.

Results: Bio-ADM levels increased after cardiac surgery on CPB from a median preoperative level of 12 (IQR, 12.0–14.8) pg/mL to a maximum postoperative level of median 48.8 (IQR, 34.5–69.6) pg/mL (p < 0.001), with peak levels at 24 hours postoperatively. Bio-ADM concentrations correlated with longer CPB time (r = 0.268; p = 0.022), greater postoperative fluid balance (r = 0.429; p < 0.001), increased demand for vasoactive/ inotropic medication (r = 0.415; p < 0.001), and hydrocortisone therapy for postoperative vasoplegia (postoperative bio-ADM with hydrocortisone treatment median 129.1 [IQR, 55.4–139.2] pg/mL vs. without hydrocortisone treatment median 37.9 [IQR, 25.2–64.6] pg/mL; p = 0.034). Patients who required pleural effusion drainage revealed higher bio-ADM levels than those who did not (pleural effusion drainage: median 66.4 [IQR, 55.4–90.9] pg/mL vs. no pleural effusion drainage: median 40.2 [IQR, 28.2–57.0] pg/mL; p < 0.001).

Conclusion: Elevated bio-ADM levels were found in children with CHD after cardiac surgery on CPB and higher levels correlated with clinical signs of capillary leakage. Therefore, bio-ADM should be considered as a biomarker for capillary leak in this patient cohort.

No conflict of interest has been declared by the author(s).

Publication History

Article published online:
13 February 2024