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.