Biventricular function on early echocardiograms in neonatal hypoxic-ischaemic encephalopathy

Aim: To compare early (<24 hours) echocardiograms (ECHOs) in infants with perinatal hypoxic-ischaemic encephalopathy (HIE) undergoing (i) therapeutic hypothermia (TH), (ii) normothermia and (iii) normal controls. Methods: This was a single-centre retrospective review of clinical early ECHOs of term infants with moderate or severe HIE and controls (with a normal ECHO <72 hours of age). Right (RVO) and left ventricular output (LVO), RV and LV myocardial performance index (MPI), systolic to diastolic duration ratio (S/D) and eccentricity indices (EI) in systole and diastole were compared using ANOVA. Results: Among infants with HIE (n = 56, 38 in the TH and 18 in normothermia groups), 14 (25%) infants died and 42 survived. Significantly elevated biventricular MPI, lower RVO and LVO and pulmonary hypertension (abnormal EI, higher RV S/D and bidirectional or right-to-left ductal shunt) were found in groups with HIE, compared to controls (n = 35). LV MPI was lower in HIE-TH, compared to the HIE-normothermia group. Infants with HIE who died (n = 14) had a significantly lower EId [0.77 (0.09) vs. 0.83 (0.08), p = 0.021] compared to survivors (n = 42). Conclusion: Infants with perinatal HIE have ventricular dysfunction; those who died had significantly lower EId than survivors; this association needs to be further validated.