QT interval in newborns of different ethnic origin: usefulness of neonatal ECG screening.

The cost-effectiveness of neonatal electrocardiographic (ECG) screening has been questioned. The objective of this study was to establish normal values for the QT interval in newborns of different ethnic origin. Between 2005 and 2006, ECGs were obtained during the first 48 h of life from 1305 at-term newborns at the Hospital del Mar in Barcelona, Spain. The mean corrected QT interval (QTc) was 417.79+/-28.47 ms. A QTc longer than 440 ms was observed in 240 newborns (18.33%). The frequency of a pathologic QTc in Spanish newborns was 17.9%, compared with 27.7% in those of Maghreb or Near Eastern origin (P=.016), and 28.2% in those of Indian or Pakistani origin (P=.033). The QTc may vary for genetic reasons. A routine neonatal ECG is advisable only in ethnic groups in which the QTc is lengthened, to help counter the greater risk of sudden death in these infants.