Background Chronic lung disease (CLD): oxygen requirement at 36 weeks corrected gestational age (CGA) is a significant neonatal morbidity which can have adverse effects on cardiac function until pre-school age.¹ Conventional echocardiographic techniques such as fractional shortening (FS) and left ventricular output (LVO) may not identify cardiac dysfunction in preterm infants. We have previously demonstrated that tissue Doppler imaging (TDI) is useful in assessment of myocardial function in these patients.²

Objectives To compare myocardial function in preterm infants born at.

Methods 50 preterm infants with CLD (25 receiving low flow nasal cannula oxygen and 25 receiving non-invasive positive airway pressure) and 22 without CLD (controls) had an echocardiogram at approximately 36 weeks CGA. Myocardial function was evaluated using FS, LVO and TDI. Ethical approval and written parental consent were obtained.

Results Median GA and birth weight of infants with CLD was lower than controls (27 wk (23–31) vs. 29 wk (23–31); 829 g (500–1790) vs.1030 g (570–1700)). There was no difference in persistence of PDA, tricuspid regurgitation, left ventricular FS and LVO between the groups. However, using TDI right ventricular peak systolic (S’) and late diastolic velocities (A’) (p < 0.001) were all significantly higher in CLD cases compared with controls.

Conclusion Cardiac dysfunction in this vulnerable group of patients can be better identified with TDI compared to FS and LVO. Using TDI may improve the identification of cardiac dysfunction and guide further management.

References

1. Koroglu OA et al. Neonatology 2013;104(4):283-289

2. Negrine RJS et al . Arch Dis Child Fetal Neonatal Ed 2012;97 F304-F306