[The diameter of the large arteries in the first 3 years of life. An echocardiography study].

The diameters of the great arteries at their origin and also more distal are important parameters for deciding which operation technique should be performed in cyanotic congenital heart diseases. In 130 normal newborn and infants (age between 1 day and 3 years, with a weight of 2,2 through 20 kg) who were examined because of heart murmur diameters of main pulmonary artery, right pulmonary artery, left pulmonary artery, aortic root, ascending aortae, aortic arch, and isthmic region were measured echocardiographically. Then correlations between age and diameters, and weight and diameters were calculated. The mean diameter of ascending aorta grew from 0.84 cm through 1.4 cm, of main pulmonary artery from 0.75 cm through 1.4 cm, of right pulmonary artery from 0.43 cm through 0.86 cm, of left pulmonary artery from 0.42 cm through 0.88 cm, of aortic arch from 0.68 cm through 1.44 cm, and of isthmic region from 0.47 cm through 0.83 cm. The best correlation was found using linear functions between weight and diameters. The "growing-velocity" of ascending aorta was 0.043 cm/1 kg weight gain and 0.05 cm/1 kg weight gain for main pulmonary artery (0.033 cm/1 kg weight gain for right and 0.035 cm/1 kg weight gain for left pulmonary artery). The great arteries grow linearly within the first 3 years of life. The echocardiography was a reliable tool to calculate "growing-velocities".