[Fetal echocardiography. A horizontal study of biometry and cardiac function in utero].

The anatomy and the cardiac growth in normal fetal heart was studied by real-time-directed M-mode ultrasound from the 19th gestation week until term. A correct fetal cardiac M-mode recording was obtained in 94 out of 144 women (65%). Echocardiographic variables were plotted against gestational age and respective correlation coefficients were determined by linear regression analysis. A comparison between the variables was studied by paired t-test. Left ventricular, right ventricular, left atrial and right atrial chamber size, interventricular septum thickness, right and left wall thickness, aortic and pulmonary diameter all increased linearly with age. Right ventricle (10.1 +/- 3.1) was slightly larger than left ventricle (9.2 +/- 2.8 mm) (p less than 0.001), the pulmonary artery (7.9 +/- 1.9 mm) was greater than the aorta (7.6 +/- 2 mm) (p less than 0.001), while no significant difference was noted between left atrium (10.8 +/- 3.5 mm) and right atrium (10.1 +/- 2.6 mm), right ventricular wall thickness (2.7 +/- 0.9 mm) and left ventricular wall thickness (3.0 +/- 1.1 mm). The ratios of left ventricular/right ventricular diameter, left atrial/right atrial and left atrial/aortic diameters, the relative wall thickness and arterial vessels diameters did not change significantly throughout the pregnancy. The ratio interventricular septum/posterior wall thickness was 1.14 +/- 0.36 and ratio of 1.5 or greater was found in 14.5% of the fetal normal heart. The ratio left atrial/aortic diameter was 1.32 +/- 0.21 and left atrium was significantly greater than aorta (p less than 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)