[Quantitative echography of the fetal heart]

One hundred and twenty two fetal echocardiograms were performed during normal pregnancies between the 20th and 38th weeks of gestation. Freeze frame M mode and 2D imaging was used to perform the following measurements: right and left systolic and diastolic ventricular dimensions, dimensions of the two atria, aortic and pulmonary artery dimensions, fractional shortening of both ventricles, ratio of right ventricular to left ventricular end diastolic dimensions RVEDD/LVEDD, ratio of pulmonary artery to aortic dimensions PA/Ao. The causes of error or failure were analysed. The results classified by gestational age show progressive growth of all structures which double their size during the second half of the pregnancy; the "physiological" septal hypertrophy reported by some workers was not observed in this series; similarly, paradoxical septal motion was only present in 3% of the fetuses studied. The RVEDD/LVEDD ratio approached unity, which questions the classical but hypothetical concept of physiological right ventricular preponderance, a concept also queried by recent fetal Doppler intracardiac flow studies. The repertory of normal values is particularly useful for the detection of cardiac malformations and for the surveillance of some pregnancies with a high risk of cardiomyopathy, as in maternal diabetes.