Biomedical subjects
Publications and source records attributed to T Rosenfeld.
A Soviet nuclear pacemaker is described. It is a large VOO bipolar pacemaker, probably nonprogrammable. It has unique electrode connectors. No isotope leak or excessive radiation hazard was detected. Because we had no knowledge of its end-of-life markers and because of the impossibility of assuming long-term safety, the device was removed.
A 26-year-old woman with severe pliable mitral stenosis underwent successful balloon mitral valvuloplasty at the end of the second trimester of pregnancy. The indication for intervention was severe shortness of breath during most daily activities, despite combined beta-blocker and diuretic treatment (FC III, NYHA). After use of a 2 x 19 bifoil balloon there was significant clinical and hemodynamic improvement. Shortness of breath disappeared, the mean mitral valve diastolic gradient decreased from 24 to 7 mmHg and the mitral valve area increased from 0.8 to 1.8 cm. There were no complications of the treatment, and estimated radiation exposure of the fetus was less than 0.2 rad. Subsequent abdominal ultrasound examination revealed normal fetal functioning. 2.5 months after mitral dilatation delivery was normal. Balloon mitral valvuloplasty may safely be used instead of surgery as a palliative procedure for relief of symptoms in pregnant women with severe pliable mitral stenosis.
Several diseases, at times, may be confused with scabies. We report the diagnosis and treatment of scabies in two patients. Their eruptions recurred and persisted and eventually developed blisters. The skin biopsy specimens submitted for light microscopy and immunofluorescence were considered to be consistent with bullous pemphigoid. Both patients were treated successfully with lindane and remained disease free for up to 6 months of follow-up.
A case is presented in which a to-and-fro murmur was heard at auscultation. Cross-sectional echocardiography, combined with Doppler examination, showed that the murmur was produced by flow across the neck of a left ventricular pseudoaneurysm.
This paper describes the experience of a cohort of elderly patients who were discharged after attending the accident and emergency department of a large Australian teaching hospital. Before-and-after comparisons of aspects of physical functioning revealed a considerable loss of independence in the period immediately after the visit to the hospital. Subsequent hospital admission or death was observed in 30 of the 90 patients studied. It is suggested that elderly patients discharged from the accident and emergency department are at risk and require special consideration and a high index of suspicion in terms of evaluation at the time of presentation. Before discharge, account should be taken of aspects of physical and mental function, social networks, and community supports available to each patient. A lowered threshold for admission is recommended on the basis of the high rate of return found in this study.
A case of a week old female baby, admitted because of apathy, hypothermia, dyspnea, jaundice and cyanosis is described. She had the characteristic phenotype of Turner's syndrome with normal karyotype. Signs of severe heart failure were present. Therapy with diuretics, digoxin, dopamine and mechanical ventilation were unsuccessful, and the patient died several hours after her admission. The anatomopathological examination revealed the presence of hypoplastic left heart syndrome with mitral atresia and aortic atresia, atrial septal defect, double outlet right ventricle, and a patent ductus arteriosus.
Aortic stenosis (AS) is an uncommon complication during pregnancy, but when it occurs it results in significant maternal and fetal morbidity and mortality. We present a gravida with severe AS in which aortic valve replacement was performed in the 3rd trimester of her pregnancy. She had severe AS with mild aortic regurgitation and severe congestive heart failure. Fetal heart rate and uterine activity were monitored and recorded during the operation. The pregnancy was carried uneventfully to term and the patient was delivered of a healthy baby. The literature is reviewed and recommendations are made for the management of AS during pregnancy.
Myocarditis may present with a variety of electrocardiographic patterns. However, polymorphous ventricular tachycardia (PVT), potentially a highly malignant ventricular arrhythmia, has not been described in acute myocarditis. As far as we know, this is the first report of this arrhythmia in that condition. It is characterized by unusual resistance to both the common pharmacological and nonpharmacological approaches. This report of a 28-year-old woman demonstrates the role of PVT as a potential cause for sudden death among patients with subclinical myocarditis.
25 patients with end-stage renal failure were studied by different echocardiographic techniques before and immediately after hemodialysis using M-mode, 2-dimensional and Doppler echocardiography. Preload reduction after dialysis was manifested by a decrease in body weight, in left atrial diameter and in the left ventricular end-diastolic dimension. Doppler flow patterns immediately after dialysis showed reduction in early diastolic velocities across the atrioventricular valves and increase in the flow velocities across the semilunar valves and the peripheral A-V fistula. The flow velocity integral, calculated by Doppler echocardiography, was lower after dialysis. Significant improvement in left ventricular myocardial function after dialysis was correlated with reduction in afterload and increase in myocardial contractility.
Gunshot wounds and traumatic injuries are the main causes of acquired arteriovenous fistulas. The high cardiac output associated with such fistulas depends mainly on the size of the pathological communication and the degree of reduction in the systemic vascular resistance that results. Since the findings on cardiac examination in these patients may mimic those of valvular heart disease or dilated cardiomyopathy, careful attention should be paid to noncardiac physical findings, such as thrill and/or continuous murmur over the traumatic or surgical scar. We describe a 64-year-old man who developed severe left heart failure 39 years after a gunshot injury in the left lower quadrant of the abdomen. This had led to an acquired arteriovenous fistula between the left internal iliac artery and the left common iliac vein.
A 75-year-old man began suffering from intermittent episodes of superior caval venous syndrome, seven years after implantation of an endocardial pacemaker via the right cephalic vein. The obstruction of the superior caval vein was confirmed by venography and computed tomography of the chest. Changes of the intrathoracic pressure were considered to be the mechanism responsible for the intermittence of the syndrome.
In order to assess prospectively the incidence and significance of venous thrombosis early after permanent transvenous pacemaker implantation venographic studies were carried out in 40 consecutive patients. The venograms performed between 1 and 6 months (mean 4 months) after the implantation were normal in 31 patients (77%), in six patients (15%) they showed partial venous obstruction and in three patients (8%) total obstruction. Between 6 and 12 months (mean 9 months) the venograms of five patients, that were previously normal, showed partial venous thrombosis. No changes were found in the venograms performed later. Only two of 14 patients with thrombosis of the great veins was clinically symptomatic and developed arm edema, that resolved spontaneously within about a month. No difference in incidence of abnormal venograms was found according to the type of insulation, the polarity of the electrode and the route of entry.
Female conjoined twins were delivered after 42 weeks' gestation, but they died within a few minutes of birth. They were dicephalus, dibrachius and dipus conjoined twins with two separate spines and fusion of the trunk and the pelvis. The pericardial sac was common, and the heart was a single structure. The atrial complex was a common chamber with an attempt at division into two parts by a circular ridge of tissue; the ventricular complex was formed by three chambers which were all communicating between each other in the superior margin of their muscular interventricular septum.
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The quantum yield of the primary photoprocess in light-adapted bacteriorhodopsin (phi 1) was determined at room temperature with low-intensity 530 nm neodymium laser excitation, with bovine rhodopsin as a relative actinometer. The observed value of phi 1 - 0.25 +/- 0.05, and the previously determined parameter phi 1/phi 2 - 0.4 [where phi 2 denotes the quantum efficiency of the back photoprecess from the primary species K (590)] imply that phi 1 + phi 2 approximately equal 1. This feature, also characterizing the photochemistry of rhodopsin, bears on the nature and mechanism of the primary event in both systems.
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