Protein-losing enteropathy after Fontan operation.

Generalized edema resulting from severe protein-losing enteropathy occurred in three patients 12, 15, and 17 months after the Fontan operation. One patient originally had tricuspid atresia and the other two, univentricular heart disease. At operation a conduit had been inserted between the right atrium and pulmonary artery. Apart from the protein loss, the patients were in good health. The cardiac catheterization data obtained 0.8 to 2.4 years (median 1.3 years) after operation in the three patients with protein-losing enteropathy were compared with those of 18 patients in whom Fontan's operation had been performed because of tricuspid atresia (eight patients) or univentricular heart disease (10 patients). All had atriopulmonary connections. The mean right and left atrial pressures and systemic blood flows measured by dye dilution in the patients with and without protein-losing enteropathy did not differ. However, the patients with protein-losing enteropathy had a higher diastolic right atrial pressure. Since maximal antegrade flow in the superior vena cava after Fontan's operation occurs during atrial diastole, these observations suggest that an increase in diastolic right atrial pressure may result in protein-losing enteropathy because of impairment of blood flow and therefore congestion in the superior vena cava, subclavian vein, and thoracic duct.

Rectal 13N-ammonia test (13N-liver/heart ratio), hepatic sinusoidal pressure and prevailing portal flow direction in cirrhosis of the liver.

The 20 minutes' liver/heart activity ratio after rectal administration of 13N-ammonia was abnormally low (less than 2.25) in 12 of 26 patients with cirrhosis of the liver. An abnormal conventional rectal arterial ammonia test (porta-systemic shunts), an abnormally low urea index (prevailing hepatofugal portal venous flow direction), marked portal hypertension (hepatic sinusoidal pressure greater than or equal to 8 mm Hg), ascites and extreme enlargement of the spleen occurred significantly more often in the patients with an abnormally low 13N-liver/heart ratio than in those with a ratio greater than or equal to 2.25. There was no correlation between the 13N-liver/heart ratio and absence or presence of oesophageal varices. The non-invasive rectal 13N-ammonia test appears to be an easy to perform, informative test in cirrhosis of the liver.

Value of systolic time intervals in assessing severity of congenital aortic stenosis in children.

Simultaneous recordings have been made of electrocardiogram, phonocardiogram, carotid pulse tracing, left ventricular pressure, and aortic pressure in 27 children with aortic valve stenosis and 3 children with membranous subaortic stenosis. Peak systolic pressure difference ranged from 10 to 110 mmHg (1.3 to 14.6 kPa). None of the patients had congestive heart failure and cardiac output was in the normal range in all. Total electromechanical systole, left ventricular ejection time, and pre-ejection time were corrected for heart rate, age, and sex. Mild stenosis (peak systolic pressure difference less than or equal to 50 mmHg (6.7 kPa)) was present in 18, severe stenosis (peak systolic pressure difference greater than 50 mmHg) in 12 patients. The externally measured pre-ejection time and ejection time proved to be nearly equal to the corresponding intervals measured internally; from these data it is concluded that pre-ejection time and ejection time in children with aortic stenosis can be measured reliably by non-invasive methods. Mean values for corrected total electromechanical systole and ejection time were prolonged, but the corrected pre-ejection time did not differ from the normal value. When corrected time intervals were plotted against severity of the aortic stenosis as expressed by the peak systolic pressure difference or the aortic valve orifice index, a wide scatter was found. It is concluded that a normal ejection time is strong evidence against a peak systolic pressure difference of more than 50 mmHg (6.7 kPa) or an aortic valve orifice index less than 0.70 cm2 per m2 BSA. A prolonged ejection time, however, may occur in mild as well as in severe stenosis. Total electromechanical systole and pre-ejection time have no value in predicting the severity of aortic stenosis in children.