Accurate internal correction for the magnification of cineangiocardiography in infants with congenital heart disease

Correction for x-ray magnification at cineangiocardiography (cine) requires accurate localization of the level of the left ventricle (LV). This study compared LV volumes calculated using a standard external reference object (area grid) with volumes calculated using an intracardiac radiopaque catheter balloon in cine studies of casts (n = 26), normal lambs (n = 15), and infants with congenital heart disease (n = 11). Comparisons of LV volumes calculated using both correction methods with true cast displacement volumes were excellent (r = 0.99). Correlations of both methods were highly significant (p less than 0.001) in casts (r = 0.99), normal lambs (r = 0.97), and in infants (r = 0.83). The absolute percent difference (17.6 +/- 2.4 SE%) between LV volumes calculated by both methods was greatest in infants. Thus external localization of the LV may be more difficult in infants. The radiopaque balloon provides convenient accurate correction for cine x-ray magnification and calculation of LV volumes, particularly since flow-directed catheters are widely used for diagnostic cine ventriculography in infants.     

Thyroid function at birth in infants of 30 to 45 weeks' gestation.

Serum T4 was measured in cord blood of 2,683 infants of gestational ages 30 to 45 weeks and birth weights of 1,460 to 5,250 gm. In addition, serum TBG was measured in 180, and serum TSH in 125 of these infants. Mean serum T4 increased with gestational age from 9.4 microng/dl at 30 weeks to 11.7 at 45 weeks. TBG varied from 3.1 to 11.4 mg/dl but showed no correlation with gestational age. There was a positive correlation between T4 and TBG. Serum TSH levels showed a significant negative correlation with gestational age, decreasing from 15 micronU/ml at 30 weeks to 7 micronU/ml at 45 weeks, while the serum T4/TSH ratio increased from 0.6 to 1.6. The results indicate that cord, T4 varies mainly with TBG, and to a lesser extent with gestational age.     

Patent ductus arteriosus complicating the respiratory distress syndrome in preterm infants.

In 46 preterm infants with RDS the patency of the ductus arteriosus was established by single film aortography or by clinical diagnosis and confirmation at surgery. The estimated left-to-right shunt through the PDA by aortogram correlated well with the heart size and the clinical diagnosis of heart failure. In 14 infants massive cardiomegaly and heart failure with a PDA occurred before the appearance of a heart murmur. Twelve infants had severe RDS and 34 had mild or moderate RDS. Massive cardiomegaly occurred significantly earlier in infants with severe RDS. It is suggested that ductal ligation is indicated when an infant with massive cardiomegaly requires IPPV and whose aortagram shows that all of the contrast material is in the pulmonary arteries and none in the aortic arch. A heart murmur may or may not be present.     

Serum concentrations of immunoglobulins E and G and α2-macroglobulin in childhood renal disease

Serum concentrations of IgE, IgG, and α₂-macroglobulin (α₂M) were determined in 67 children with renal disease and in appropriate controls. IgE concentrations were significantly elevated in patients with renal disease and proteinuria, including those with minimal change nephrotic syndrome (MCNS). IgG concentrations were lower and α₂M concentrations higher in patients with proteinuria than in patients without proteinuria. In 16 patients with nephrotic syndrome who had a decrease in proteinuria with therapy, there was a concomitant decrease in mean serum IgE level. All nine with MCNS had a decrease in serum IgE following therapy whereas eight of the nine had a concomitant increase in serum IgG. The findings suggest the possibility that IgE may play an etiologic role in the proteinuria of childhood nephrotic syndrome, and that both elevated serum IgE and proteinuria may represent unusual responses to antigens that are seldom identified. Elevations of IgE secondary to lowered IgG or to entirely nonspecific alterations in IgE metabolism in proteinuric renal disease are other possibilities. Further studies to elucidate the role of IgE in renal disease, including the nature of the altered metabolism of this immunoglobulin, are warranted.     

Genetic obesity in rats. I. The effects of food restriction on body composition and hypothalamic function

The effect of controlled food intake was compared in genetically obese rats of the “Fatty” (Zucker) strain and lean animals. One group of six Fatty rats were fed ad lib., another six were pair fed to lean controls, and a third group were fed two-thirds the intake of lean animals. All rats were trained to eat in 6 hr each day. Weight gain was abolished in the Fatties fed a restricted diet, but these animals did not reduce their body fat. Fatty rats fed ad lib. or pair fed were more efficient than lean rats in storing calories as fat. Pituitary, ovary, and uterus were significantly smaller in the Fatty rats. Limiting food intake did not restore these organ weights toward normal. Among the three groups of Fatty rats, body weight was positively correlated with the weight of the adrenal, pituitary, ovary, uterus, and liver. Urine volume was higher in the ad-lib. and pair-fed Fatties than in the lean animals but restriction of food intake reduced urine output below controls. The uptake of ¹²⁵I by the thyroid was significantly reduced in all groups of Fatties, but thyroid weights did not differ. Serum FSH was higher in the restricted Fatties but LH was not. These studies suggest that previously observed differences in hypothalamic endocrine function do not result from hyperphagia.