Normal ECG Standard in Preterm and Term Neonates in the First Day of Life

ABSTRACT

PURPOSE: To obtain the normal standard of the electrocardiogram(ECG) in newborn infants, METHODS: Standard 12-lead ECG recordings of 146 healthy neonates of gestational age above 30 weeks recorded in 24 hours after birth were analyzed for the following parameters heart rate, QRS axis, PR interval, QTc interval, R and S wave amplitude. RESULTS: The mean gestational age of preterm(between 30 and 37 weeks) and term infants was 33.2 +/-2.4 and 38.4+/-3.2 weeks, and the mean birth weight was 2,168+/-371 g and 3,254+/-436 g, respectively. There was no meaningful difference between two groups in heart rate, PR interval, QTc interval, and QRS axis. Amplitudes of R waves in V1>-V6 leads and S waves in V2, V3 and V5 leads in term baby group were significantly larger than those in preterm baby group. The sum of amplitudes of R and S waves was largest in V2. The amplitude of combined R+S waves in V2 and V3 leads was significantly larger than that in V5 and V6 leads in both groups. This difference was more prominent in tbaby group. CONCLUSION: The results suggest that the increase in cardiac muscular mass and progressive right ventricular predominance are in accordance with the increase in gestational age.