Abstract
Objective Heart rate variability (HRV) indicates cardiac autonomic nerve activity and is influenced
by brain damage during the neonatal period. We aimed to determine whether a correlation
exists between the HRV of extremely preterm neonates and neurodevelopmental test scores.
Study Design Electrocardiogram data of neonates were assessed and HRV patterns in extremely preterm
neonates with severe intraventricular hemorrhage (IVH; n = 6) and those with no/mild IVH (n = 28) were compared. We analyzed the relationship between HRV and neurodevelopmental
outcomes at 18 months (n = 21) and 3 years (n = 23) in extremely preterm neonates.
Results HRV was significantly associated with IVH severity in extremely preterm neonates
(p < 0.05). Neonates with severe IVH exhibited increased HR and decreased mean R-to-R
interval (NN) compared with neonates with no/mild IVH. HRV parameters significantly
decreased in the severe IVH group, but not in the no/mild IVH group, suggesting that
both sympathetic and parasympathetic activities decreased in neonates with severe
IVH. Additionally, decreased HR and increased NN were significantly related to impaired
neurodevelopmental outcomes in the no/mild IVH group at corrected ages of 18 months
and 3 years, respectively (all p < 0.05).
Conclusion HRV was significantly associated with IVH severity and neurodevelopmental outcome
in extremely preterm neonates. HRV can distinguish extremely preterm neonates who
subsequently had severe IVH from those who had no/low-grade IVH. HRV may identify
extremely preterm neonates needing adjuvant neuroprotective interventions. These findings
warrant further investigation in a larger population of extremely preterm neonates.
Key Points
-
HRV was associated with IVH severity.
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HRV can predict subsequent severe IVH in extremely preterm neonates.
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HRV are predictive of neurodevelopmental outcomes in extremely premature neonates
with low-grade IVH.
Keywords
extremely preterm neonates - heart rate variability - intraventricular hemorrhage
- neurodevelopmental impairment