PubMed Health⌕ Search

Biomedical subjects

D R Fischer

Publications and source records attributed to D R Fischer.

At least 37 records · Page 2Linked to original sources

Balloon pulmonary valvuloplasty in a child with Ebstein's anomaly and valvar pulmonary stenosis.

We performed a balloon pulmonary valvuloplasty in a child with Ebstein's anomaly using the standard technique. The procedure reportedly has not been performed in the face of this defect and, although difficult, was safely and successfully accomplished. In patients with Ebstein's anomaly and right ventricular outflow obstruction compounded by pulmonary valve stenosis, application of this technique may delay the need for surgical intervention.

Catheterization↗

The cross sectional anatomy of ventricular septal defects: a reappraisal.

The cross sectional echocardiographic description of holes in the ventricular septum has been unsatisfactory, chiefly because there are so many classifications of this defect. The accurate description of the anatomy of individual defects, from cross sectional images, is more important than attempts to fit them into a preconceived classification. One hundred specimens of hearts with a ventricular septal defect were reviewed to identify those features that are of value in the interpretation of cross sectional images. Three groups of defect were identified: those which abutted the central fibrous body, those with a margin partly formed by an area of fibrous continuity between the leaflets of the aortic and pulmonary valves, and those with entirely muscular margins. Each group had features that were readily discernible in cross section. Other features of the defects seen in the cross sectional images identified defects that opened between the two ventricular inlets, defects that opened between the two subarterial outlets, and those that extended solely into the trabecular septum. The criteria for describing the anatomy of defects were established in hearts with normal connections, but they were found to be equally applicable in hearts with discordant atrioventricular connection, discordant ventriculoarterial connection, common arterial trunk, and double outlet from the morphologically right ventricle. Cross sectional imaging, by echocardiography and potentially by other techniques, provided a uniquely detailed and precise description of the morphology of ventricular septal defects.

Abnormalities, Multiple↗

Extracorporeal membrane oxygenation in children. New trends.

At the Children's Hospital of Pittsburgh the extracorporeal membrane oxygenation program was started in 1980. The results of our experience from 1980 to 1985 were previously reported. In the past 2 years 39 additional newborn infants have been treated with this modality, with an overall survival rate of 79% (31/39). This survival rate is much better than that obtained in 33 neonates who had been treated in the previous 5 years (54%; p less than 0.05). A new aspect of our extracorporeal membrane oxygenation program is the use of total apneic lung rest for persisting pulmonary interstitial emphysema during support with the oxygenator. Six neonates were treated with this technique because of worsening pulmonary interstitial emphysema during extracorporeal circulation. Five of them survived. Another indication for extracorporeal membrane oxygenation in our pediatric population has been left ventricular or biventricular failure after cardiopulmonary bypass. Four of our seven patients treated for this indication are long-term survivors. At present, because of the impossibility of using other forms of left ventricular assist devices in the pediatric population, it seems that extracorporeal membrane oxygenation is the most effective treatment for left ventricular failure after cardiopulmonary bypass. From our experience, even in the absence of long-term follow-up of patients supported with extracorporeal membrane oxygenation, it appears that the benefits of this therapeutic modality far exceed the risks in the high-risk population for which it is being used.

Cardiopulmonary Bypass↗

Experience with heart transplantation in children.

Between March 1981 and March 1986, 200 orthotopic heart transplantations were performed at the University of Pittsburgh. Fourteen of those procedures were carried out in children 2 to 16 years of age. Two children received combined liver and heart transplants; one because of familial hypercholesterolemia with associated ischemic heart disease, and the other because of dilated cardiomyopathy associated with intrahepatic biliary atresia. Eight patients had dilated cardiomyopathy, and two had myocarditis. Two had heart transplantations for congenital heart disease: one had multiple muscular ventricular septal defects repaired in infancy and had an associated cardiomyopathy, and the other developed a cardiomyopathic ventricle from a congenital right coronary artery to right atrial fistula. Chronic immune suppression consisted 0.2 to 0.5 mg/kg/d of prednisone and 5 to 50 mg/kg/d cyclosporine, with the addition of antithymocyte globulin for unresolved moderate or severe acute rejection. There were three early postoperative deaths: one from intracranial bleeding, one from Pseudomonas mediastinitis, and one from ischemic injury to transplanted organs. Early postoperative complications included reversible renal failure, hypertension, and seizures. Late problems were related to allograft rejection and side effects of cyclosporine and corticosteroids. Significant rejection episodes occurred in all patients surviving longer than 2 weeks, with seven requiring antithymocyte globulin. Two patients died 8 months following transplantation of severe acute and chronic rejection; another patient required retransplantation for ischemic cardiomyopathy resulting from chronic rejection but subsequently died of recurring rejection 3 months after the second transplantation.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗

Echocardiographic findings before and after liver transplantation.

Echocardiographic studies were performed in 73 patients with various types of chronic liver disease. They were 0.5 to 19 years old (mean 5). Thirteen patients underwent follow-up echocardiography 1 to 13 months (mean 6) after liver transplantation. Preoperatively 60 patients (82%) showed evidence of high cardiac output (cardiac index greater than 4 liters/min/m2); these patients manifested increased left ventricular (LV) and left atrial dimensions and a thickened LV posterior wall. Transvenous contrast echocardiographic study confirmed the presence of intrapulmonary arteriovenous shunting in 4 patients. Studies after liver transplantation revealed a reduced LV end-diastolic dimension in 12 patients. Cardiac index was reduced a mean of 35% after transplantation (p less than 0.001). This study suggests that liver transplantation improves common hemodynamic abnormalities in chronic liver disease.

Adolescent↗

Ventricular septal defect associated with aneurysm of the membranous septum.

The most common variety of ventricular septal defect, a perimembranous defect, is frequently associated with a so-called aneurysm of the membranous septum. Previous studies have suggested that ventricular septal defects associated with an aneurysm of the membranous septum tend to spontaneously decrease in size or close more than defects without such an aneurysm. To better define the natural history of this entity, clinical and catheterization data from 87 patients with ventricular septal defect and aneurysm of the membranous septum were reviewed. The initial evaluation was made at a median age of 0.3 years (range 0.1 to 11), with the final evaluation at a median age of 10 years (range 1.5 to 20) and a median duration of follow-up of 8.6 years (range 1.2 to 18.8). Approximately 75% of the ventricular septal defects had a small or no left to right shunt at last evaluation. Overall, 48 patients (55%) had no significant change in the size of the defect, and 39 (45%) showed improvement during the period of observation. Only four patients (5%) had spontaneous closure of the defect. Of the 49 patients who presented with a large left to right shunt, with or without congestive heart failure, 23 (47%) had persistence of a shunt large enough to warrant surgery. When spontaneous improvement occurred, it did so by 6 years of age in all but one patient. Therefore, a continued tendency for a ventricular septal defect associated with an aneurysm of the membranous septum to spontaneously decrease in size or close after this age may be less likely than previously suggested.(ABSTRACT TRUNCATED AT 250 WORDS)

Aneurysm↗

Magnesium and calcium dietary intakes of the U.S. population.

Dietary intake levels of calcium and magnesium, as well as calcium/magnesium ratios, were assessed for 12 age/sex groups of the U.S. population through use of USDA's 1977-78 Nationwide Food Consumption Survey. Results indicated that a majority of the U.S. population consumed less than recommended amounts (NRC-RDA) of both calcium and magnesium. Approximately 60% of 0 to 5 year olds and 40% of 6 to 11 year olds had average daily calcium intakes of less than 800 mg, while 60 and 85% of the male and female adolescents, respectively, had intakes below the recommended level of 1,200 mg/day. Approximately 80 to 85% of the adult female groups and 50 to 65% of the adult male groups had average intakes below recommended levels. With the exception of children ages 0 to 5 years, the average daily magnesium intakes of all age/sex classes were below the NRC-RDA. Magnesium consumption was particularly low among adolescent females, adult females, and elderly men, with 85, 80-85 and 75%, respectively, of the population groups having average magnesium intakes below their respective NRC-RDA. Furthermore, the majority of the population groups did not consume appropriate proportions of these two minerals to obtain optimal calcium/magnesium ratios. While adolescent females and adult females had more appropriate ratio values than other segments of the population, these ratios principally resulted from their very low intakes of calcium. The most inappropriate calcium/magnesium ratios, observed for children, male adolescents, and young adult males, were, in general, due to their more appropriate calcium intakes and their low magnesium intakes.

Adolescent↗

Cholesterol, saturated fatty acids, polyunsaturated fatty acids, sodium, and potassium intakes of the United States population.

The USDA's 1977-1978 Nationwide Food Consumption Survey was utilized to assess dietary intake levels of cholesterol, fatty acids, sodium, and potassium by several age/sex groups of the U.S. population. Results indicated that mean cholesterol intakes for all male age groups of 12 yr and older exceeded 300 mg/day while the mean intakes of females and children were less than 300 mg/day. However, approximately 30% of each age group of adult females exceeded 300 mg cholesterol per day and only about one-third of the adult males had average intakes of less than 300 mg/day. Between 39% and 44% of total kilocalories were obtained from fat consumption with saturated fatty acids contributing 13-15%, polyunsaturated fatty acids contributing 5-6% and oleic acid contributing 12-14% of total kilocaloric intake. We found that 90% of children ages 6-11 yr and adult females had saturated fatty acids intakes of less than 40 gm/day; 90% of all men had intakes of less than 55 gm/day. At least 90% of all age/sex groups averaged intakes of polyunsaturated fatty acids of less than 26 gm/day. Average daily sodium intakes for each age/sex group (excluding table salt) were within the limits considered safe and adequate. However, approximately 4% of each age group of adult females and about 25% of each of the three younger adult male groups had average sodium intakes of 4000 mg/day or more. Average daily potassium intakes were somewhat low, ranging from 1584 mg/day for children ages 0-5 yr to 2735 mg/day for males ages 51-64 yr.

Adult↗

Tetralogy of Fallot with absent pulmonic valve: analysis of 17 patients.

Seventeen patients with tetralogy of Fallot (TF) and absent pulmonic valve were seen at Children's Hospital of Pittsburgh from 1958 to 1981. In 7 patients, severe respiratory symptoms developed due to bronchial compression by an aneurysmal pulmonary artery, and 6 died. In 4 patients, moderate respiratory symptoms developed. Six patients remained free of respiratory distress. Medical and surgical management of patients with respiratory distress in infancy has been frustrating and frequently unsuccessful. A 4-month-old infant with respiratory distress underwent complete intracardiac repair with valve insertion and has subsequently survived with relief of symptoms. Considering the high mortality rate in this group of patients, further attempts at aggressive surgical repair in infancy for patients with severe respiratory symptoms is warranted. An anatomic review of pathologic specimens with this anomaly confirmed previous reports of the frequent association of absence of the ductus arteriosus in patients with tetralogy of Fallot and absent pulmonary valve. The exception is noted in patients with discontinuity between the right and left pulmonary arteries in which a ductus arteriosus may be present supplying the isolated left pulmonary artery.

Abnormalities, Multiple↗

Surgical management of univentricular heart with subaortic obstruction.

In children with a univentricular heart and a rudimentary subaortic chamber, surgical relief of subaortic obstruction caused by a restrictive bulboventricular foramen is associated with high morbidity and mortality. A 6-year-old child with a univentricular heart of the left ventricular type, a rudimentary subaortic chamber, and atresia of the left-sided atrioventricular valve had pulmonary artery banding in infancy. Severe subaortic obstruction subsequently developed. At operation, the pulmonary artery was transected and the stump was anastomosed directly to the posterior aspect of the ascending aorta, diverting left ventricular blood into the aorta through the pulmonary valve. The distal pulmonary artery was anastomosed side-to-side to the ascending aorta to provide pulmonary blood flow. Cardiac catheterization fifteen months after the operation demonstrated an excellent hemodynamic result. When the pulmonary artery is adequate in size, a bypass operation by way of an anastomosis between the ascending aorta and the pulmonary artery is a relatively safe and effective means of relieving the ventricular outflow obstruction caused by a restrictive bulboventricular foramen.

Aortic Valve Stenosis↗

Ventricular inversion with normal ventriculoarterial connection and left atrial isomerism: correction by the Mustard operation.

A 2 year old boy with ventricular inversion and normal ventriculoarterial connection is described. Associated cardiac lesions included single atrium, absence of the coronary sinus, bilateral superior venae cavae, absence of the hepatic segment of the inferior vena cava with azygos and hemiazygos continuation, right aortic arch, levocardia and left atrial isomerism. At 5 days of age, the patient underwent a Waterston (aortopulmonary) anastomosis because of suspected pulmonary atresia. The correct diagnosis was established at 2 years of age and the patient had a successful Mustard operation (interatrial baffle procedure) and closure of the Waterston anastomosis. Accurate preoperative diagnosis is difficult in this rare cardiac anomaly and the reported mortality rate is high.

Cardiac Catheterization↗

Hemodynamic function after the Mustard operation for transposition of the great arteries.

Pre- and postoperative cardiac catheterization data and cinenangiocardiograms of 82 patients who survived the Mustard operation for transposition of the great arteries (TGA) were reviewed. The post-operative catheterizations were performed 20 days to 10 years after operation (mean 2.5 years). Forty-six patients (56%) had no or insignificant associated cardiac lesions, whereas 36 (44%) had ventricular septal defect, pulmonary stenosis, or both, and required surgical intervention at the time of the Mustard operation. Postoperatively, 11 patients (13%) had significant systemic venous obstruction. Of the 11 patients, 6 required reoperation, and 2 patients had evidence of restenosis or complete obstruction in the superior vena cava after reoperation. In most patients, superior vena caval obstruction was well tolerated even in the presence of high pressure in the superior vena cava. Pulmonary venous obstruction occurred in 5 patients (6%), 3 of whom had no clinical symptoms despite severe pulmonary venous obstruction, although all had radiographic evidence of pulmonary venous congestion. The incidence of obstruction was drastically reduced after the Mustard operation was modified to include routine enlargement of the pulmonary venous atrium. Tricuspid regurgitation was uncommon (10%), but did occur in patients who had transatrial closure of a ventricular septal defect. Preoperatively, left ventricular outflow obstruction occurred in 38%. In 12 patients an attempt was made to relieve the obstruction at surgery. The 6 patients who had localized obstruction had a good result, but patients with more diffuse narrowing of left ventricular outflow had little or no relief of obstruction. Mild to moderate left ventricular outflow gradients regressed spontaneously in most patients after the Mustard operation.

Adolescent↗