The intraventricular conduction time of fetal heart in pregnancies with suspected fetal growth retardation

Abstract

Electrocardiographs from 68 fetuses with ultrasound evidence of growth retardation were recorded from the maternal abdomen; QRS duration was measured and compared to normal standards previously obtained in our Institute. Of these fetuses, 54 were small-for-gestational-age at birth and 44 exhibited QRS duration values below -2 SD for their gestational age. All but one of the 14 normal fetuses showed normal QRS values (positive predictive value = 98%; negative predictive value = 57%). Of 11 fetuses with QRS duration values below -4 SD, nine were particularly small, below the 2nd centile of weight for gestation. QRS duration measurements may represent a sensitive method for identifying fetal growth-retardation. The QRS duration also seems to provide a reliable prognosis of perinatal outcome. Normal values are a reassuring factor: abnormal cardiotocographic records were observed in only 2 out of 23 cases and no low Apgar scores or perinatal deaths occurred. QRS values below -4 SD proved to be associated with abnormal cardiotocographic records (7/13), low Apgar scores (5/15) and perinatal deaths (3/15).