Mechanisms of differential growth of heart ventricles in newborn pigs.

The left ventricular free wall (LVFW) grew approximately three times faster than the right ventricular free wall (RVFW) during the first 10 days of life in neonatal pigs. Faster growth was associated with proportional increases in total RNA and messenger RNA. These findings indicated that greater capacity for protein synthesis was a major factor in accelerated growth.

Atrial automatic ectopic tachycardia due to an atrial tumor.

A dilated cardiomyopathy picture has been produced by rapid atrial and ventricular rates sustained for a long period of time in some patients. The ventricular tachycardias have in some instances been associated with ventricular tumors as the cause of the tachycardia. Once the tumor is removed, the tachycardia stops and the heart function improves.

Acute myocardial effects of chloramphenicol in newborn pigs: a possible insight into the gray baby syndrome.

Mechanical function and mitochondrial respiration were observed in newborn pig hearts in the presence of chloramphenicol. Isolated perfused hearts exposed to chloramphenicol (25, 50, or 100 micrograms/ml) demonstrated acute reductions in pressure development and cardiac output accompanied by elevated left atrial filling pressure. The effects of chloramphenicol and chloramphenicol succinate (25, 50, 100, or 200 micrograms/ml) on oxidative activity of isolated mitochondria were also investigated.

Ductus arteriosus aneurysm presenting as pulmonary artery obstruction: diagnosis and management.

The occurrence of pulmonary artery obstruction in an 8 day old infant as a complication of an aneurysm of a nonpatent ductus arteriosus is reported, together with the echocardiographic and angiographic findings. To relieve the obstruction, the aneurysm and an intrapulmonary thrombus were successfully removed with the use of cardiopulmonary bypass when the infant was 3 months old.

Aerobic capacity, obesity, and atherosclerotic risk factors in male adolescents.

Correlations between aerobic capacity, obesity, and atherosclerotic risk factors were evaluated in adolescents with low-to-moderate levels of physical fitness. Subjects with higher levels of fitness had a more favorable risk profile with decreased body mass index, lower systolic and diastolic blood pressure and plasma triglyceride levels, and higher plasma high-density lipoprotein-cholesterol levels. Simple linear regression analysis revealed an association between body mass index and blood pressure, plasma triglyceride and plasma high-density lipoprotein-cholesterol.

Should elective repair of coarctation of the aorta be done in infancy?

Our experience with the subclavian flap repair for coarctation of the aorta over the past 10 years includes 53 patients under 1 year of age. Of this group, 35 were newborn infants. All but two had an associated patent ductus arteriosus and 23 (66%) had associated intracardiac anomalies.

Pulsed Doppler and two-dimensional echocardiographic findings in aortico-left ventricular tunnel.

Two-dimensional echocardiography was used to make the anatomic diagnosis of aortico-left ventricular tunnel in a 1 day old infant. Pulsed Doppler echocardiography allowed directional flow to be determined within the tunnel. The findings were confirmed by cardiac catheterization and by direct visualization at the time of surgical repair.

Evaluation of the pediatric surgical patient with congenital heart disease.

Children with cardiac disease who undergo noncardiac surgical procedures may encounter risks beyond those usually associated with surgical procedures. In this article, several complicating factors seen in children with heart disease are discussed, including arrhythmias, cyanosis, congestive heart failure, pulmonary hypertension, and subacute bacterial endocarditis.

Coarctation in Taussig-Bing malformation of the heart. Surgical significance.

In a review of 126 heart specimens of simple complete transposition of the great arteries with ventricular septal defect (VSD), coarctation was noted in eight (6%). In 105 Taussig-Bing heart specimens, coarctation and/or aortic outflow tract obstruction was noted in 56 (53%) (p less than 10(-10). This was similar to our surgical experience in 26 patients with transposition and VSD or Taussig-Bing heart.

Fatty acid and glucose utilization in isolated, working fetal pig hearts.

Fatty acid uptake and the effects of long- and short-chain fatty acids on glucose utilization were assessed in isolated perfused fetal pig hearts (0.9 gestation) in which oxygenated nutrient buffer was pumped from both ventricles at controlled pressure (55 mmHg, mean arterial pressure) and heart rate (180 beats/min). When either 1.

Blood pressure response to exercise in children following the subclavian flap procedure for coarctation of the aorta.

Eight patients who underwent repair of coarctation of the aorta as infants (mean age 4.6 months) by the subclavian flap procedure were evaluated by dynamic exercise. Their mean age at the time of exercise testing was 4.

Anomalous mitral arcade: echocardiographic and angiographic recognition.

A patient with sudden onset of hemiplegia was noted to have an anomalous mitral arcade at cardiac surgery. Echocardiographic and angiographic data are correlated with the anatomic findings. The clinical significance of this anomaly is discussed.

Fatty acid and glucose utilization in isolated, working newborn pig hearts.

The effects of exogenous fatty acids on glucose uptake were assessed in isolated, working newborn pig hearts in which great vessel pressures were controlled (mean 55 mmHg) and oxygenated nutrient buffer was recirculated through the heart for 30 or 60 min. When palmitate (1.5 mM) or octanoate (1.

Perinatal changes in mitochondrial respiration of the rabbit heart.

Oxidative metabolism and citrate synthase activity during the perinatal period were assessed in isolated rabbit heart mitochondria at 27 days' gestation (27 dpc), 1 day postpartum (1 dpp) and 10 dpp. Oxygen consumption was measured during state 3 and state 4 respiration using the following substrates: glutamate, alpha-ketoglutarate, pyruvate/malate, succinate/rotenone, acetate, palmitylcarnitine, and palmityl CoA/carnitine. Results obtained from fetal and neonatal animals were compared to values obtained from adult left and right ventricles.

Carbohydrate metabolism in isolated, working newborn pig heart.

Metabolic activity of the newborn pig heart was observed by means of a preparation that allowed isolated hearts to perform a physiologic work load. A 10-min period of retrograde aortic perfusion was followed by 60 min of recirculating perfusion in which bicarbonate buffer was infused into the right atrium and ejected from both ventricles at measured pressures and flow rates. The buffer was supplemented with either glucose (10 mM), lactate (20 mM), or pyruvate (20 mM), or was unsupplemented.

Oral hydralazine in patients with pulmonary vascular disease secondary to congenital heart disease.

Two patients with pulmonary vascular obstructive disease secondary to congenital heart disease were evaluated hemodynamically before and during oral hydralazine therapy. Both patients were assessed postoperatively and had no significant residual shunts. Pulmonary vascular resistance failed to decrease, and an increase in pulmonary arterial pressure occurred because of increased cardiac output secondary to systemic arteriolar dilatation.

Congenital diaphragmatic hernia. New concept in management.

The newborn infant with a congenital diaphragmatic hernia (CDH) who develops severe respiratory distress requiring operative repair within the first 24 hours of life represents one of the most challenging problems in pediatric surgery. The mortality in these infants still exceeds 50% and has historically been attributed to ventilatory insufficiency secondary to pulmonary hypoplasia. However, the primary abnormality in these neonates seems to be an increase in pulmonary vascular resistance with an elevation of pulmonary artery pressure, right-left ductal shunting, preductal shunting and progressive hypoxemia.

Modified Shumacker repair of transposition of the great arteries.

Seven infants weighing from 6.4 to 10.3 kg underwent correction of transposition of the great arteries by the venous transposition operation as described by Shumacker.