Circulating immune complexes in sera of children with neuroblastoma: correlation with stage of disease

The presence of circulating immune complexes (ICS) in freshly drawn sera of 67 children with neuroblastoma was studied by the Raji cell radioimmunoassay of Theofilopoulos et al. (J. Clin. Invest. 57: 169--182), with particular emphasis on the correlation of levels of ICS with stage of disease and changes attributable to treatment. There was a close correlation between amount of complexes and stage of disease and treatment. Levels of ICS increased as the stage of the disease advanced, and were significantly higher (P less than 0.005) in stage IV than in all other stages combined. When patients with stage IV disease were subdivided into "before," "during," and "after" treatment groups, there was a significant decrease in ICS levels as treatment progressed. Studies of complement and complement components did not give such a clear relationship. A significant decrease of hemolytic C1 values was found in patients with "active disease" compared to normal age-matched controls. Some high C3 levels, determined immunochemically, were associated with low hemolytic levels of C3, which were attributed to C3 cleavage detected by immunoelectrophoresis. Based on our survival data, ICS, which were significantly different in 20 patients now decreased when compared to those of other patients, are very valuable in the prognosis of neuroblastoma.

Composite replacement of the aortic valve and ascending aorta

This report comprises 16 consecutive patients with ascending aortic aneurysms caused by cystic medical necrosis. We replaced the ascending aorta and aortic valve with a tightly woven Dacron graft containing a Lillehei-Kaster valve prosthesis and implanted the coronary ostia in the sides of the graft. All but two patients had massive aortic insufficiency. Postoperative catheterization was performed in 13 patients, and all surviving patients have been seen within the past 6 months. There was one perioperative death (6 percent) and two late deaths. Eleven survivors are in Class I and two are in Class II (N.Y.H.A.). Angiographically demonstrated late complications have included psuedoaneurysms of the coronary ostium (two), paravalvular leak (one), and pseudoaneurysm of the distal suture line (one). Two of these four patients were asymptomatic. Two of the four patients have had successful repair of these defects and a third is awaiting operation. Compositive replacement carries a low operative risk and minimizes problems of intraoperative bleeding. In view of the incidence of late suture line problems, routine angiography 6 to 12 months postoperatively is recommended. If new symptoms occur or if there is a change in the cardiac silhousette on chest roentgenogram, the patient should be recatheterized.

Hemodynamic evaluation of Lillehei-Kaiser and Starr-Edwards prosthesis

The central-flow low profile disc-valve prosthesis has been offered as an alternative to ball- and tissue-valve prostheses. Extensive laboratory investigation with both pulse duplicator and experimental animals has been reported for the Lillehei-Kaster prosthesis. A series of patients receiving this prosthesis underwent postoperative cardiac catheterization to better define the hemodynamic function of this prosthesis in vivo. Because of the variations in reports of hemodynamic data from various institutions, the results of post-operative studies in an earlier group of patients with Starr-Edwards prostheses were used as a standard for comparison. Good hemodynamic function was found with the pivoting-disc prosthesis in all but the smallest valve sizes. Lillehei-Kaster and early model Starr-Edwards prostheses with equivalent tissue annulus dimensions were found to have nearly equal valve areas in vivo in the aortic position. The Lillehei-Kaster mitral valves provided larger areas than Starr-Edwards prostheses in large tissue annulus sizes.

The rate-pressure product as an index of myocardial oxygen consumption during exercise in patients with angina pectoris

In order to evaluate hemodynamic predictors of myocardial oxygen consumption (MVO2), 27 normotensive men with angina pectoris were studied at rest and during a steady state at sympton-tolerated maximal exercise (STME). Myocardial blood flow (MBF) was measured by the nitrous oxide method using gas chromatography. MBF increased by 71% from a resting value of 57.4 +/- 10.2 to 98.3 +/- 15.6 ml/100 g LV/min (P less than 0.001) during STME while MVO2 increased by 81% from a resting value of 6.7 +/- 1.3 to 12.1 +/- 2.8 ml O2/100 g LV/min (P less than 0.001). MVO2 correlated well with heart rate (HR) (r = 0.79), with HR x blood pressure (BP) (r = 0.83), and, adding end-diastolic pressure and peak LV dp/dt as independent variables, slightly improved this correlation (r = .86). Including the ejection period (tension-time index) did not improve the correlation (r = 0.80). Thus, HR and HR x BP, both easily measured hemodynamic variables, are good predictors of MVO2 during exercise in normotensive patients with ischemic heart disease. Including variables reflecting the contractile state of the heart and ventricular volume may further improve the predictability.

Aortic regurgitation associated with ventricular septal defect. Echocardiographic and hemodynamic observations

Ventricular septal defect is sometimes associated with aortic regurgitation. In this report, an echocardiogram demonstrating dramatic prolapse of the noncoronary cusp into the left ventricular outflow tract and ventricular septal defect in a patient with Down's syndrome and ventricular septal defect, confirmed by angiographic studies, is presented. The echocardiogram supports the concept of anatomic lack of support of the aortic ring due to a deficient septum and hemodynamically significant flow of blood to the right ventricle through the ventricular septal defect, resulting in trauma to aortic cusps and prolapse.

Methotrexate in blood, urine, and cerebrospinal fluid of children receiving high doses by infusion

Methotrexate was determined in plasma (31 patients), urine (eight patients), and cerebrospinal fluid (two patients) after high doses (35 to 150 mg/kg) by infusion, with citrovorum factor rescue. Concentrations in plasma were proportional to dose at 6, 24, 72 h after beginning treatment, but this trend was very minimal for samples obtained at 48 h. Clinical toxicity probably will not be serious if the methotrexate concentration in the serum is less than 4.5 X 10(-6) mol/liter at 48 h after the start of a 6-h infusion. In both of the two patients so examined, therapeutic concentrations appeared in cerebrospinal fluid after intravenous infusion of the drug. A kinetic enzymic method, radioassay, and radioimmunoassay all yielded similar results for drug concentrations.

Methotrexate in blood, urine, and cerebrospinal fluid of children receiving high doses by infusion

Methotrexate was determined in plasma (31 patients), urine (eight patients), and cerebrospinal fluid (two patients) after high doses (35 to 150 mg/kg) by infusion, with citrovorum factor rescue. Concentrations in plasma were proportional to dose at 6, 24, 72 h after beginning treatment, but this trend was very minimal for samples obtained at 48 h. Clinical toxicity probably will not be serious if the methotrexate concentration in the serum is less than 4.5 X 10(-6) mol/liter at 48 h after the start of a 6-h infusion. In both of the two patients so examined, therapeutic concentrations appeared in cerebrospinal fluid after intravenous infusion of the drug. A kinetic enzymic method, radioassay, and radioimmunoassay all yielded similar results for drug concentrations.

Demonstration of acid mucopolysaccharides in the trabecular meshwork of the Rhesus monkey

The ability to demonstrate AMPS in the trabecular region in the normal eye of the Rhesus monkey was shown to be critically dependent upon technical variation. Staining the fixed specimen prior to dehydration and embedding permits the uniform demonstration of AMPS in the trabecular region of the Rhesus monkey and shows it to be hyaluronidase-sensitive. Electron microscopy using the modified technique shows the reaction products to be present within the trabecular band, the intertrabecular spaces, and the canal of Schlemm. More impressive distribution was seen in the basement membrane of trabecular endothelium intimately related to the cell wall and in the ground substance and basement membrane of the endothelium of the inner wall of the canal Schlemm. The technique is also successful in the human eye and suggests a greater abundance of trabecular AMPS in open-angle glaucoma.

Hemodynamic changes during ventricular pacing in patients with complete heart block and aortic and mitral valvular heart disease

Increasing the heart rate to near normal in patients with complete heart block (CHB) and slow ventricular rates may lead to greater improvement in ventricular function than when the heart rate is increased from normal to more rapid heart rates. Improvement in ventricular function is usually manifested by a decrease in left ventricular end-diastolic pressure (LVEDP) and volume and by an increase in contractility. In patients with both CHB and valvular heart disease improvement in ventricular function during pacing may be modified by the nature of the valvular disease. Hemodynamic data from six patients with both valvular heart disease and CHB were compared with those from ten patients with CHB and normal cardiac valves. Hemodynamic studies were performed at slow or idioventricular rates and again after increasing the heart rate to more nearly normal levels by ventricular pacing. When obstruction to left ventricular inflow (mitral stenosis) co-existed with CHB, increasing the heart rate resulted in a reduction of an elevated LVEDP to normal. This resulted in only a small increase in left atrial pressure in spite of a striking increase in the mean left atrial-ventricular gradient. When obstruction to left ventricular outflow prevailed (aortic stenosis), improvement in cardiac function was manifested mainly by a decrease in LVEDP and was accompanied by a decrease in left ventricular stroke work. When a large regurgitant volume (aortic insufficiency) was added to a ventricle which has enlarged subsequent to CHB, there was striking elevation in ventricular filling pressures which returned to more nearly normal levels when the heart rate was increased. This was accompanied by a reduction in regurgitant stroke volume in the patient in whom it was measured. Thus, an increase in heart rate may be especially beneficial to those patients with CHB who also have valvular lesions which contribute to an increase in LVEDP and end-diastolic volume. Careful hemodynamic evaluation is helpful in determining appropriate therapy in these patients.