Background and aims In preterm infants, postnatal myocardial adaptation may be influenced by bronchopulmonary dysplasia (BPD). We aimed to describe the development of left ventricular function by serial 2D-Doppler, and speckle tracking echocardiography (2D-STE) in infants with and without BPD during the neonatal period in comparison to anthropometric and conventional haemodynamic parameters.
Methods Prospective echocardiography on day of life (DOL) 1, 7, 14, and 28 in 119 preterm infants <1500 g birth weight, of whom 36 developed BPD (oxygen supplementation at 36 gestational weeks). Non-BPD and BPD infants differed significantly in median[IQR] gestational age (25.5[24–26.5] weeks vs. 29[27–30]weeks, p < 0.001) and birth weight (661[552–871]g vs. 1100[890–1290]g, p < 0.001).
Results The rapid growth of length and body weight during the first 4 weeks of life was not matched by increased speckle tracking parameters. Infants with BPD differed significantly (p < 0.001) from those without BPD firstly, for all anthropometric parameters and conventional haemodynamic parameters except heart rate and secondly, for 2D-STE parameters global longitudinal systolic strain rate (GLSSR) and longitudinal systolic strain (LSSR) at the left free midwall segment. In infants with BPD, GLSSR (p < 0.001) and LSSR (p < 0.01) were significantly higher during the first week of life after which the differences disappeared. Low intra- and inter-observer variability was seen for longitudinal systolic strain and strain rate mid septum with a median coefficient of variation <4.6%.
Conclusions Reproducible 2D-STE measurements are possible in preterm infants <1500 g. There are early (DOL 1 and 7) ventricular changes (GLSSR and LSSR) in very low birth weight infants who develop BPD.