Pilot study to validate endothelium collection from pulmonary artery balloon catheter in children

Pediatric pulmonary hypertension (PH) has high morbidity and mortality, with an estimated 5-year survival of 75% regardless of underlying cause. Pediatric PH most commonly affects infants born preterm who develop lung disease of prematurity as well as those with congenital heart disease. Current therapies have been adapted from the treatment of adult PH. One barrier to the study of pediatric PH is the lack of live tissue samples or primary cells for research. In this manuscript, we describe methods to obtain pulmonary endothelium from cardiac catheterization of pediatric patients with PH. We applied methods previously described in adult patients undergoing isolated right heart catheterization to obtain viable endothelium from pulmonary wedge catheters in pediatric patients. Primary cells were grown and passaged, and endothelial phenotype was confirmed by light microscopy, immunohistochemistry, flow cytometry, migration assay, and tube formation assay. To our knowledge, this is the first published account of endothelial culture from pulmonary wedge balloon catheters in pediatric patients.