Patent ductus arteriosus (PDA) remains one of the most common cardiovascular problems in preterm neonates. The aim of this study was to analyse the clinical impact of PDA in preterm infants with low weight.
Methods A total of 81 preterm infants with low birth weight were evaluated. Echocardiographic analysis was used to diagnose PDA, to determine the magnitude of the transductual shunt and to ascertain its haemodynamic significance. The birth weight infant was defined as: extremely low (ELBW) ≤1000 g, very low (VLBW) 1001–1500 g and low weight (LBW) 1501–2000 g.
Results PDA was diagnosed in 29 preterm infants (35.8%), being more frequent in preterm infants with ELBW than VLBW and LBW infants (59.3% vs. 25% vs. 23.8%, p = 0.008). The preterm infants with PDA were characterised by: greater haemodynamic instability 48.3% vs.13.7% [OR 5.86 (95% CI 1.99–17.3, p = 0.001], mechanical ventilation 82.8% vs. 41.2% [OR 6.85 (95% CI 2.25–20.8 p = 0.001], bronchopulmonary dysplasia 17.2% vs. 2% [OR10.4 (95% CI 1.15–94.1,p = 0.013]. There were not significant differences in the presence of intraventricular haemorrhage or necrotizing enterocolitis (24.1% vs. 18%, p = 0.513 and 6.9% vs. 7.8%, p = 0.87, respectively). Mortality was slightly higher in preterm infants with PDA than those with closed ductus, 8 (27.6%) vs. 6 (11.8%), p = 0.073. In the multivariate analysis the PDA was not a predictor of mortality [HR 2.17 (95% CI 0.31–15.2), p = 0.434].
Conclusions In our series, PDA could be to increases neonatal morbidity, increasing the risk of respiratory problems, especially in preterm infants with ELBW.