title: Patent Ductus Arteriosus in the Preterm Infant: An Update on Morbidity and Mortality.
abstract: BACKGROUND
  Patent ductus arteriosus (PDA) is a common factor complicating the care of the preterm infant, but controversy remains regarding the long term effects of PDA and iatrogenic closure of PDA.
  
  
  METHODS
  Studies presenting data relevant to the relationship between PDA and mortality and morbidity were identified via a systematic literature review. These studies were classified based on PDA exposure in the case and control groups. The data was abstracted and summarized using linear modeling, resulting in summary estimates of mean effect size (odds ratio).
  
  
  RESULTS
  Recently published data suggests that a significant relationship between PDA and mortality, bronchopulmonary dysplasia/chronic lung disease, necrotizing enterocolitis, or retinopathy of prematurity is unlikely. However, the data related to mortality leaves room for some debate. Quantitative analysis of the data shows that PDA is a risk factor for intraventricular hemorrhage and related studies suggest this risk may carry over into long term neurological outcomes.
  
  
  CONCLUSIONS
  Further efforts to better understand the physiologic consequences of PDA and its closure in preterm infants is necessary. A focus on new biochemical or physiologic factors that mediate or confound any apparent effect of PDA and are themselves amenable to targeted therapy is imperative to further progress in improving the outcomes of these patients.
authors.affiliation: DeVos Cardiovascular Research Program of Van Andel Institute-Spectrum Health, 333 Bostwick Avenue NE, Grand Rapids, MI 49503, USA. eric.kort@helendevoschildrens.org.
authors.forename: Eric J
authors.initials: EJ
authors.lastname: Kort
mesh_terms: D004374:Ductus Arteriosus, Patent / Q000150:complications / Q000401:mortality* / Q000503:physiopathology / Q000601:surgery; D020345:Enterocolitis, Necrotizing / Q000150:complications / Q000503:physiopathology; D006801:Humans; D052577:Infant, Extremely Low Birth Weight; D062071:Infant, Extremely Premature; D007231:Infant, Newborn; D008026:Ligation / Q000009:adverse effects / Q000379:methods; D008171:Lung Diseases / Q000150:complications / Q000503:physiopathology; D009017:Morbidity; D065886:Neurodevelopmental Disorders / Q000150:complications / Q000503:physiopathology; D012178:Retinopathy of Prematurity / Q000150:complications / Q000503:physiopathology; D012307:Risk Factors