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Objectives The goal of this study was to report the early and late complications experienced in atrial septal defect (ASD) transcatheter closure. Background Atrial septal defect transcatheter occlusion techniques have become an alternative to surgical procedures. A number of different devices are available for transcatheter ASD closure. The type and rate of complications are different for different devices. Methods Between December 1996 and January 2001, 417 patients (mean age: 26.6 ± 19 years) underwent transcatheter occlusion of secundum type ASD. Complications were categorized into major and minor. Two different devices were used: the CardioSEAL/STARFlex in 159 patients and the Amplatzer septal occluder in 258 patients. Results Thirty-four patients experienced 36 complications during the hospitalization (8.6%, 95% confidence interval: 6.1% to 11.1%). Ten patients underwent elective surgical repair because of device malposition (three patients) or device embolization (seven patients). Twenty-four patients experienced 25 minor complications: unsatisfactory device position or embolization. Devices were retrieved using a gooseneck snare and/or a basket; 11 patients experienced arrhythmic problems. Other complications were: pericardial effusion, thrombus formation on the left atrial disc, right iliac vein dissection, groin hematoma, hemorrhage in the retropharynx and sizing balloon rupture. Two patients had late complications: peripheral embolization in the left leg one year after implantation of an Amplatzer device and sudden death 1.5 year later. Conclusions Our series of patients with ASD by transcatheter occlusion shows that the procedure is safe and effective in the vast majority of cases. To further reduce the complications rate, the criteria of device selection according to ASD morphology and some technical tips during implantation are discussed.

Experiments of magnetostatic surface‐wave propagation in YIG slabs have been performed which show a transverse distribution of rf field of Gaussian shape. Previous theories are for uniform internal dc field and give uniform or cosine rf distribution. The observed Gaussian shape can be tentatively explained in terms of propagation in a nonuniform lossy medium, the nonuniformity being a consequence of the internal dc field profile.

Sub-Coulomb heavy ion scattering of 20 Ne on 148,150,152 Sm at 70 MeV has revealed a strong depletion of the elastic scattering flux at backward angles, systematically increasing with the collectivity of low-lying target states. A comparison with a semiclassical Coulomb absorption model and coupled channel calculations is given.

Inelastic scattering spectra have been measured with 245 MeV incident energy /sup 9/Be ions on a /sup 208/Pb target. They show large excitation of the /sup 208/Pb giant quadrupole resonance. Distorted-wave Born-approximation calculations are reported and compared with the data.

Analysis and experiments show the extreme dispersion of magnetostatic delay lines. A suitable parameter to characterize the amount of dispersion present has been found to be the maximum output energy contained in a time interval equal to the input pulse duration. The time occurrence of this maximum value gives a convenient measure of the group delay. The pulse shape and energy content versus delay have been determined both theoreticaly and experimentally for axially magnetized circular rods. The results show that delays beyond two to three times the input pulse duration cannot be obtained with more than 50 percent of the output energy contained within the original pulse duration.

The growth of a carrier wave propagating through a negative‐differential‐mobility semiconducting sample is discussed under nonuniform dc bias conditions. A simple analytical expression for the over‐all numerical gain is given in terms of current density and of the input and output carrier‐wave velocities only. Applications to n‐type GaAs are discussed.

Repair of localized bilateral congenital pulmonary venous stenosis with living autologous atrial tissue was accomplished in two patients, 3 and 4 months of age. The tip of the left atrial appendage was opened and used as an onlay patch to widen the stenotic area of the left pulmonary veins, leaving a double pathway for venous return. A flap of interatrial septum was evaginated through an incision in the right side of the left atrium and used as an onlay patch to widen the stenotic area of the right pulmonary veins. Effective relief of obstruction was demonstrated by nearly normal postrepair pulmonary artery pressure in each and early postoperative angiography in one. Although we believe this method of repair will increase the probability of a lasting result, further experience and subsequent late reevaluation are needed to demonstrate its long-term effectiveness.

The use of Polyacrylamide gel to stimulate biological tissues at microwave frequencies is presented; formulation and preparation procedures are discussed. Measurements of complex permittivity in the range from 0.75 to 5.5 GHz, together with its temperature sensitivity are reported. Thermal and otpical properties have also been measured: the polyacrylamide is transparent and may be used as a phantom material in designing and testing applicators for microwave hyperthermia and for dosimetry studies. The use of polyacrylamide gel to simulate biological tissues at microwave frequencies is presenteed. Formulation and preparation procedures are discussed. Measurements of complex permittivity in the range from 0. 75 to 5. 5 GHz, together with its temperature sensitivity, are reported. Thermal and optical properties have also been measured: the polyacrylamide is transparent and may be used as a phantom material in designing and testing applicators for microwave hyperthermia and for dosimetry studies.

One of the major postoperative complications of total anomalous pulmonary venous connection is obstruction of the pulmonary veins. This event may be apparent immediately after surgery when it is usually due to congenitally obstructed veins or later when it may be the result of failure of commensurate growth of the left atrium-common vein anastomosis or of scarring at the anastomotic site. The exact location of the obstruction becomes, then, of paramount importance in deciding if the patient can be helped by further surgery. At cardiac catheterization, pulmonary artery wedge injection was the only angiographic technique that visualized the site and degree of pulmonary venous obstruction in the case reported here.

Clinical and pathologic findings of an unusual case of cardiac malformation are presented. The main features were those of atresia of the right atrioventricular valve associated with two distinct atrioventricular orifices connecting the morphologically left atrium to the underlying morphologically left ventricle. Other distinguishing characteristics were ostium secundum atrial septal defect, normally related great arteries, with the aorta arising from the main ventricular chamber and the pulmonary artery from the anterior and right-sided outlet chamber, and infundibular and valvular pulmonary atresia.

A microwave heating method and an associated numerical method for computing the reaction velocities in a single experiment are proposed for rapid determination of the activation energy of enzymatic reactions. Application of this new technique to different enzymatic reactions is reported.

Tetralogy of Fallot associated with atrioventricular (AV) canal is a well-recognized cardiac malformation; its surgical repair carries a high mortality, which is related partly to the complexity of the defect and partly to incomplete diagnosis. Hence an accurate preoperative diagnosis is essential. This communication describes the angiographic features observed in 17 patients with tetralogy of Fallot and AV canal with emphasis on the morphology of the right AV valve as seen during the right ventriculogram. A complete anatomic diagnosis can be consistently made from right and left ventriculograms performed in axial projections.

Authors have examined 14 pregnant patients with renal involvement by systemic lupus erythematosus. Variations in blood creatinine, proteinuria and blood pressure were considered in the prepregnancy, pregnancy and postpartum periods in relation to the histologic results of renal biopsy and obstetric outcome.

The ultrastructural pattern of fibroblasts involved in the healing process of laser-treated tissues has been investigated. This study has been performed on the uterine cervix, the epithelial abnormalities of which are frequently treated by laser. Observations carried out immediately and two and seven days after treatment, have demonstrated that: fibroblasts show an active and almost uniform pattern; myofibroblasts are not present; and macrophages are limited in number. This healing process is interpreted as a proliferative pattern of the connective tissue which differs from that of some benign tumors and of healing wounds.

Of 602 patients referred for portal hypertension during a 20 year period, 18 children (mean age of 5.0 years) and 29 adults (mean age of 26.5 years) had thrombosis in the portal bed with a healthy liver (7.8 per cent incidence). In 29 of the 47 patients we studied, the causative factor remained obscure. Variceal hemorrhage occurred in all and was the indication for our observation and treatment. In 11 adult patients (mean age of 22.1 years), surgical treatment was not performed because of reluctance of the patient or because of technical reasons: nine of the patients rebled and one patient died because of massive bleeding. Direct procedures on esophageal varices had a high rate of rebleeding (seven of 11 patients) independent of the age of the patient when the operation was performed. In 13 patients, shunting offered a good chance of long term protection: three of the 13 rebled at a mean follow-up study of 5.7 years. No recurrence of bleeding was observed in 15 patients when variceal eradication had been obtained after chronic endoscopic sclerotherapy at one to eight years of follow-up study (mean of 3.9 years). The data from this study indicate that sclerotherapy should be the first choice of treatment to control recurrent bleeding in extrahepatic portal hypertension caused by thrombotic obstruction, particularly in the young patient.

Twenty-six patients receiving adriamycin for osteogenic sarcoma had serial echocardiographic assessments of their left ventricular function. A statistically significant deterioration of function was noted throughout the course. Ventricular function tended to normalize in the period following cessation of adriamycin. The velocity of circumferential fibre shortening (Vcf) and ejection fraction (EF) were the best parameters. Sudden declines in these values resulted in us withholding therapy until the parameters again improved. Fatal congestive heart failure was seen in only one patient. Echocardiography thus provides the clinician with a valuable tool enabling one to improve the therapeutic usefulness of adriamycin by removing much of the uncertainty over the development of cardiotoxicity.

This paper presents the results of an environmental investigation in a plastic-ware industry using RF sealers. Environmental measurements have demonstrated the presence of strong electric fields the intensity of which: (1) reaches significant levels from the health-protection point of view only in proximity to the applicators; (2) often exceeds the maximal levels allowed by all standards (including the most permissive) for short duration exposures, especially in the region of the hands. Results of a cross-sectional study on the health of 63 female workers are related to the observed RF exposure. A statistically significant correlation was found to exist between RF exposure and some minor health effects—eye irritation, upper limb paresthesias, and vitreous body disorganization.

A one-day-old full-term female infant with massive "cardiomegaly" developed marked respiratory distress soon after birth. The two-dimensional (2D) echocardiogram demonstrated a 4 X 5-cm cystic mass adjacent to the left ventricular free wall. Computed tomography (CT) confirmed the presence and dimension of the cyst and CT number indicated the fluid within the cyst to be serous. A pericardial cyst was successfully removed at thoracotomy. Two-dimensional echocardiography and CT, both noninvasive procedures, are fully adequate tools in the diagnosis of pericardial cysts in the neonate, so that invasive investigations may be avoided.

In this study we compared the results obtained during GnRH pulsatile therapy for ovulation induction in the same patients receiving successively GnRH by subcutaneous (10 mcg/90') and intravenous route (2.5 or 5 mcg/90'). Our data suggest that intravenous administration is the most effective procedure for restoring fertility, either in terms of hormonal levels (oestradiol and gonadotropin peaks) or ovulation rate (100% of ovulatory cycles on GnRH treatment versus 25% on subcutaneous administration). With regard to intravenous GnRH therapy, the dose of 2.5 mcg/90' may be more advisable and safe from ovarian overstimulation.

Complete septation of a double inlet left ventricle with left anterior subaortic outlet chamber was carried out successfully as a staged procedure during the first two years of life in a patient with severe pulmonary hypertension and an abnormal left atrioventricular valve. In contrast with isolated pulmonary artery banding, which rarely has led to a satisfactory septation or modified Fontan operation, this technique achieved good initial palliation and uncomplicated intracardiac repair. It should be considered for infants with univentricular atrioventricular connection, two atrioventricular valves, and excessive pulmonary blood flow.

Energy spectra and angular distributions for peripheral reactions induced by 16 O on 208 Pb at 20 MeV/ A can be explained in terms of the intrinsic nucleon motion of the excited projectile, in a manner similar to the interpretation of projectile fragmentation reactions at 2.1 GeV/ A .

A 17-year-old patient with tricuspid atresia, palliatively corrected by a right Glenn and a left Potts anastomosis during his early childhood and a banding of the left pulmonary artery 6 years ago, developed a false aneurysm of the left pulmonary artery secondary to the erosion of the band fabric through the vascular wall with subsequent thrombosis, infection, and leakage. The diagnosis was confused by both chest roentgenography and angiography but was accurately made by postcontrast computed tomography (CT). We stress the importance and usefulness of CT in the diagnosis of a false aneurysm, not demonstrated by angiography.

A prospective clinical and echocardiographic diagnosis of single ventricle was made in 42 patients. Each was evaluated for the number of atrioventricular (A/V) valves, presence of an outflow chamber (OC), A/V valve-semilunar continuity, and orientation of the great arteries. Angiographic correlations were subsequently obtained in 40 and autopsies in 12. The overall diagnosis of single ventricle was substantiated in 39. Two other patients diagnosed as single ventricle by angiography were thought to have large ventricular septal defects on echocardiography. Tricuspid valve was interpreted as septum in one. The angiographic diagnosis of single ventricle was incorrect in another, correctly diagnosed by echocardiography and confirmed at pathology. The differential diagnosis also included A-V canal, L-transposition of the great arteries, double outlet right ventricle, and tricuspid atresia. This last condition has to be differentiated on clinical evidence. The echocardiograms were of particular value in determining the number of A/V valves. Two great arteries were demonstrated in 74% of patients and their relationship was correctly determined in 79% of these. Both imaging techniques agreed closely as to A/V valve-semilunar continuity and presence of an OC, but both showed some inaccuracies compared to pathological specimens. The echocardiogram helps both in planning catheterization and in evaluating the overall diagnosis.

We have identified 12 patients with endocardial cushion defect and marked under-development of the left ventricle. Most of these patients had significant obstructive anomalies of the aortic arch. Pathologically, the left ventricle was very small, but without endocardial fibroelastosis, significant subaortic narrowing was evident, resulting from maladherent atrioventricular valve tissue to the left ventricular outflow tract, and the left ventricular posterior leaflet component of the atrioventricular valve was both grossly deficient and dysplastic. In all 12 a large ostium primum atrial communication was present, but the ventricular contribution to the defect was small. The clinical presentation of severe, intractable congestive heart failure in these neonatal patients would suggest the diagnosis of typical hypoplastic left heart syndrome. Important departures in some of these patients included a leftward, superior and counterclockwise frontal vector on the electrocardiogram and a widely split second sound. Selective biplane angiocardiography will reveal the underdeveloped left ventricle, with an elongated, fixed, 'gooseneck' deformity of the left ventricular outflow tract, severe 'mitral' regurgitation, and a small ascending aorta. Selective right ventriculography will opacify the very much larger right ventricle and pulmonary artery. Finally, these cases broaden the concept of double inlet right ventricle and exaggerated displacement of the atrioventricular canal towards the bulbus cordis.

An applicator of the electric type for the RF heating of living tissues is described. It consists essentially of an unbalanced capacitor where the RF current return is provided by a large groundplane electrode. A water layer is an integral part of the electric design, offering a relative independence from variations in the position of the electrodes with respect to the body being treated. The water also eleminates the detrimental effects of the high field concentrations at the edges of the "hot" electrode, and is additionally used for surface cooling.

Polyacrylamide gel is suggested as a new and convenient material for simulating the electrical behavior of biological tissues in experimental studies of heat deposition by electromagnetic means. The advantages of polyacrylamide are: 1) excellent optical transparency, 2) solid elastic, 3) easily shaped into complex forms, 4) readily prepared with a complete range of highly reproducible values of electrical parameters, which can also be combined to simulate various different tissues in complex structures. The material is also low-cost and readily available. The preparation of the material is explained and all the relevant data for obtaining the electrical properties of interest are given. The thermal behavior is also important and is investigated. Attention is concentrated onto the short-wave frequency range, where phantom studies are essential, but the possibility of using the same material at microwave frequencies is also pointed out.

The repair of an ostium secundum atrial septal defects (ASDs) by an open heart operation is a safe procedure associated with low mortality and morbidity. Transcatheter closure of ASDs is a less invasive method of repairing ASDs and may also be the procedure of first choice in residual postsurgical ASD.

A description is given of a microstrip radiator consisting of a circular patch in water and working at 130 MHz. The use of deionized water as a high-permittivity material for the 'substrate' allows the realization of compact, low-weight applicators for direct-contact, medium-depth treatments. The water filling the radiator also provides a good electrical transition between the antenna and the treated tissues and prevents surface overheating. Depths up to 6 cm and maximum cross sections larger than 10 cm diameter can be reached, with surface temperatures of 4-5 degrees C. >