Abstract
Objective : Patent ductus arteriosus (PDA) is a common complication among premature infants, and it may be responsible for prematurity-related complications, such as bronchopulmonary dysplasia (BPD). It is unclear whether different interventional methods contribute to the severity of BPD. To date, surgical ligation and the transcatheter approach have shown equal success in premature infants with hemodynamically significant PDA after medical treatment failure. Immediate improvement in the respiratory condition after transcatheter closure has been reported. However, the short-term pulmonary outcome has not been clarified yet. Methods : This retrospective study investigated infants born with a body weight less than 1000 g and underwent either surgical ligation or transcatheter closure of PDA in a single tertiary institution. The infants were divided into groups according to the type of procedure (surgical ligation or transcatheter occlusion). The primary outcome was the severity of BPD at discharge or at post-menstrual age of 36 weeks. The outcome was analyzed with logistic regression. Results : Forty-four patients met the inclusion criteria, and of these, 14 underwent transcatheter occlusion and 30 underwent surgical ligation. The overall birth body weight and gestational age ranges were not different. The univariate model revealed an association between the procedure type and BPD severity. The multivariate model confirmed associations of BPD severity with procedure type and severe respiratory distress syndrome requiring surfactant after adjusting for confounders. Conclusion : Compared with the transcatheter approach, surgery for PDA in extremely preterm infants is associated with severe BPD at discharge. Further large-scale studies are needed to determine the exact mechanism.
Introduction
Patent ductus arteriosus (PDA) is a common cardiovascular complication among premature infants, and it may be responsible for prematurity-related complications. The ductus arteriosus is a vessel between the pulmonary circulation and systemic circulation in a fetus.1 In most term infants, the ductus arteriosus closes spontaneously. However, in premature infants, the ductus often fails to close spontaneously. The spontaneous closure rate has been shown to be inversely related to the birth gestational age, and it ranges from 13% to 98%. 2
In premature infants, a hemodynamically significant PDA has been reported to be associated with complications, such as pulmonary hemorrhage, 3; 4 bronchopulmonary dysplasia (BPD),5; 6 intraventricular hemorrhage, 7; 8 renal dysfunction, necrotizing enterocolitis, 9neurological impairments, 10 and mortality.11; 12 A hemodynamically significant PDA will usually be treated with non-steroidal anti-inflammatory drugs, such as ibuprofen and indomethacin. A PDA may fail to respond to medical treatment and may require non-pharmaceutical interventions. Surgical ligation is a well-established procedure for a PDA that has not responded to medical treatment. However, surgical ligation has been shown to be associated with the development of BPD. 2; 13
Recently, transcatheter interventions involving ductus arteriosus closure have been used in premature infants. Wang et al. reported the detailed process and experience of performing this technique in very low birth weight infants. 14 Numerous studies have compared complications and success rates between transcatheter techniques and surgical ligation, and no statistically significant differences were noted. Furthermore, a comparison of the short-term effects after transcatheter techniques and those after PDA ligation revealed that transcatheter techniques improved the pulmonary score earlier. The authors reported the immediate benefits of respiratory trajectory following the transcatheter closure of PDA.15 However, the short-term impacts on the severity of BPD at discharge have not been reported, especially for extremely premature infants. Therefore, this retrospective study was conducted in a single institution to investigate the association between the different procedure types of PDA interventions and the severity of BPD among extremely premature infants requiring intervention for a hemodynamically significant PDA.
Material and Methods