Electrocardiographic Corrected QT (QTc) Dispersion Value as a Predictor for Estimation of Neonatal Mortality in Pre-Term Neonates

Abstract

Introduction: Electrocardiographic (ECG) corrected QT (QTc) interval and dispersion were used as prognostic variables in adult patients and limited studies showed the relationship between QTc prolongation and dispersion with some clinical situations in newborn babies. Aim: In the present study, we compared the electrocardiographic (ECG) variables such as QTc interval and dispersion of healthy full-term and pre-term neonates with those who suffered from non-cardiac illnesses. Methods: This prospective cohort study involved 127 neonates including four study groups: normal full-term neonates, ill full-term neonates, normal pre-term neonates and ill pre-term neonates. Neonates with fever, apnea, poor feeding, tachypnea, muscle retraction, grunting, reduced neonatal reflexes, positive blood culture or antibiotic therapy > 3 days were considered as ill neonates. QTc interval and dispersion were calculated and compared among the four groups. Results: QTc interval was significantly (p = 0.012) higher in ill pre-term neonates in comparison with normal pre-term ones (418.74± 54.29 ms vs. 386.66± 39.26 ms). QTc dispersion was calculated and showed significantly higher mean values in ill pre-term neonates when compared with normal full-term, ill full-term and normal pre-term ones. QT dispersion and QTc dispersion of dead neonates were significantly (p= 0.0001-0.01) higher than alive ill pre-term neonates at 3, 7 and 28 days after birth. Conclusion: QTc interval and dispersion seem to represent non-invasive, reliable predictors of mortality in pre-term ill neonates, but further investigation is needed to confirm cutoff values for the risk assessment.