Biomedical subjects
E G Olsen
Publications and source records attributed to E G Olsen.
McLeod syndrome: a distinct form of neuroacanthocytosis. Report of two cases and literature review with emphasis on neuromuscular manifestations.
McLeod syndrome was originally described on the basis of a specific blood group phenotype with weak expression of Kell antigens. This erythrocyte abnormality also causes acanthocytosis. The haematological findings are associated with abnormalities in other organ systems, including neuromuscular manifestations. A 51-year-old patient was followed up for 11 years. He presented with persistent muscle creatine kinase elevation and progressive heart disease and later developed a slowly progressive neuropathy and choreic movements. His younger brother presented with grand mal seizures, involuntary movements and high muscle creatine kinase when aged 43 years. Clinical myopathy was absent in both, yet muscle biopsy showed mild myopathic changes. The presence of a motor axonopathy was supported by electrophysiological findings. One brother also showed sensory axonopathy. The movement disorder suggested accompanying basal ganglia dysfunction. Earlier reports of McLeod syndrome are reviewed with respect to neuromuscular involvement. Absence of the Kx membrane protein seems to be the cause of this multi-system disorder.
The pathogenesis of dilated cardiomyopathy.
Using the WHO/ISFC definition and recommendations of nomenclature for cardiomyopathies, the aetiology is unknown. Over many years research has concentrated on defining pathogenetic mechanisms and owing to the widespread use of the bioptome-permitting recovery of fresh endomyocardial tissue-myocarditis has emerged as being intimately involved in the pathogenesis of dilated cardiomyopathy. In approximately 2,000 patients with a presumed diagnosis of dilated cardiomyopathy, myocarditis was found in 28% of these cases. The morphological diagnosis of myocarditis has been fraught with difficulties and, in attempt to establish criteria for its recognition, a group of cardiovascular pathologists (the author among them) met in Dallas in 1984. These criteria are detailed and categorization into acute, resolving (healing) and resolved (healed) has been emphasized because of important therapeutic implications. The cause of myocarditis has been established as being due to coxsackie B viruses. Up to recent times such findings could only be surmised by investigations such as micro-neutralization tests. It was not until the hydridization probe was employed that direct proof was provided. These studies together with immunological consequences continue to be investigated in the hope of providing a rational approach to therapy.
An atypical variant of Fabry's disease with manifestations confined to the myocardium.
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The value of endomyocardial biopsies in myocarditis and dilated cardiomyopathy.
Since the introduction of the bioptome in 1962, examination of fresh endomyocardial tissue has been undertaken progressively in many centres despite the misgivings of some investigators. In my own experience, I have examined biopsies from 3225 patients, of whom 1978 were suspected to have dilated cardiomyopathy. Of these patients, 549 showed evidence of myocarditis. Categorization into active (acute), resolving (healing) and resolved (healed) stages is important because of therapeutic implications. It is concluded that endomyocardial biopsies are of immense value in dilated cardiomyopathy where the relationship with myocarditis has become established. Even though in many cases only non-specific features are found, biopsy excludes those conditions that can result in a hypertrophied, dilated heart. Biopsy also forms the baseline for further investigations, such as virological, immunological, morphometric analyses and distinction from alcohol effects, all of which have thrown light on the pathogenetic mechanism of dilated cardiomyopathy.
Immune response to the endothelium in myocarditis, dilated cardiomyopathy and rejection after heart transplantation.
The role of endothelial cells in inflammatory heart disease and rejection after heart transplantation is only partly understood. To determine whether an immune reaction against endothelial cells occurs we examined endomyocardial biopsies from patients with myocarditis (n = 13), dilated cardiomyopathy (n = 23), no clinical rejection (n = 10) and moderate to severe rejection after heart transplantation (n = 10). These were compared to 'normal' donor hearts with monoclonal endothelial-specific antibodies EN4, Pal-E and F VIII-related antigen. Nearly all endothelial cells were stained positively with EN4. There were no significant changes in the binding of the antibodies except in rejection when Pal-E and F VIII-related antigen were significantly increased. It is concluded that apart from their possible role as antigen-presenting cells, endothelial cells are important targets in rejection after heart transplantation. Damage or cytolysis of endothelial cells may cause both altered transendothelial permeability and functional decrease in antigen presentation.
Molecular probes for detection of persisting enterovirus infection of human heart and their prognostic value.
Enteroviruses are well recognized in the aetiology of myocarditis. Molecular hybridization using enterovirus group-specific probes shows that virus can be detected in endomyocardial biopsies and persists in myocardium after the inflammation heals. Virus persistence is associated with the subsequent development of dilated cardiomyopathy, progressing to end-stage disease requiring cardiac transplantation. Infectious virus cannot usually be isolated from myocardium nor can virus-specific antigens be detected after the initial inflammatory stage. Patients with healed myocarditis or dilated cardiomyopathy may have no histological evidence of inflammation despite detection of virus-specific RNA sequences by molecular hybridization. Persisting enterovirus RNA in dilated cardiomyopathy is the strongest known predictor of poor prognosis. The molecular mechanism of virus persistence is the selection of defective virus mutants during the initial phase of disease.
Marfan's disease and Erdheim's cystic medionecrosis. A study of their pathology.
Differentiation between Marfan's disease, or its forme fruste counterpart and Erdheim's cystic medionecrosis can be made in cases of aortic dilatation or dissection. This study examined the morphological features at light microscopy of aortic tissue, removed at surgery in 10 patients with Marfan's disease. A separate group consisted of 24 patients who did not express the complete Marfan phenotype but had family members who displayed the full and typical features of the disease. This group represented the so-called 'forme fruste' variant. These two groups were compared with 12 patients in whom a histopathological diagnosis of Erdheim's cystic medionecrosis had been made. Finally normal aortic tissue from post-mortem subjects were made available representing controls. In each case the degree of elastic fragmentation and cystic change of the aortic media was assessed and tabulated. The results indicate that severe fragmentation of elastic is similarly identifiable in both Marfan and Marfan forme fruste groups and that differentiation is easy pathologically from subjects with the comparatively modest fragmentation seen in Erdheim's cystic medionecrosis. Although cystic change was encountered in all groups, its severity tended to parallel the age of the subject, and we consider from our study that Erdheim's cystic medionecrosis represents no more than an exaggerated age-related change.
Myocardial bridges: morphological and functional aspects.
OBJECTIVE: To assess the arrangement of myocardial bridges. DESIGN: A necropsy study of 90 consecutive hearts (56 male, 34 female). RESULTS: Myocardial bridges, either single or multiple, were seen in 50 (55.6%) of the 90 hearts. The left anterior descending artery was the most commonly affected artery. Thirty five of the 50 hearts which contained in total 41 muscle bridges were dissected further with a magnifying glass. Two different types of muscle bridges could be identified. Thirty one of these 41 myocardial bridges were superficial, crossing the artery transversely towards the apex of the heart at an acute angle or perpendicularly. The remaining 10 myocardial bridges crossed the left anterior descending coronary artery and surrounded it by a muscle bundle that arose from the right ventricular apical trabeculae and crossed the artery transversely, obliquely, or helically before terminating in the interventricular septum. CONCLUSIONS: The superficial type of myocardial bridge does not seem to constrict the artery during systole but the deep muscle bridges, by virtue of their relation with the left anterior descending coronary artery, could twist the vessel and thus compromise its diastolic flow. This may result in ischaemia.
The incidence of myocarditis in endomyocardial biopsy samples from patients with congestive heart failure.
We present the combined experience of three Yugoslavian cardiovascular centers in the application of endomyocardial biopsy for the diagnosis of myocarditis in patients who present clinically with congestive heart failure. The study group comprised 107 patients (mean age, 40.8 years; range, 19 to 61 years). On the basis of patient history and diagnostic tests, the following clinical diagnoses were established: dilated cardiomyopathy (85), myocarditis (16), and alcohol-induced heart disease (6). EMB samples were taken from the left ventricle (95) or both ventricles (12) by use of a King's College bioptome, with a mean of 3.2 samples per patient. Histologic evidence of myocarditis was noted in 10 of 85 patients (12%) with a clinical diagnosis of dilated cardiomyopathy, in 2 of 6 patients (33%) with alcohol-induced heart disease, and in 12 of 16 patients (75%) with a clinical diagnosis of myocarditis. There was confirmation of the clinically suspected diagnosis in 63% of cases, a change of diagnosis based on histology in 15% of cases, and nonspecific findings in 22%. However, useful information was obtained in 78% of the cases, and there was a 22% incidence of histologically proven myocarditis for the entire group. Our results indicate that endomyocardial biopsy is beneficial in determining the true incidence of myocarditis in patients with a clinical presentation of dilated cardiomyopathy.
Pars flaccida perforation in tissue culture: morphological study.
Subtotal pars flaccida perforation was effected in vitro in rat tympanic membranes. The drums were subsequently kept in tissue culture and after various intervals studied by means of light and scanning electron microscopy. No complete covering of the perforation was seen, though a marked thickening and hyperplasia of the outer, keratinizing, squamous epithelium (OE) was evident. The inner, tympanal epithelium (IE) appeared swollen, containing rounded structures in the cytoplasm especially close to the contact area with the OE. Ingrowth of OE onto the tympanal side of the drum was seen particularly in the areas where the IE was sparse and completely lacking. Complete covering of a drum perforation seems to be dependent on the formation of supporting granulation tissue, probably resulting from an inflammatory reaction in the healing area.
Gamna-Gandy nodules in a cardiac myxoma.
A 33-year-old female was admitted for surgery for removal of a left atrial myxoma. Histological examination of the tumour showed features characteristic of myxoma. Additionally, Gamna-Gandy bodies were present in the tumour. This is a rare finding.
Is endomyocardial biopsy necessary in evaluating enlarged hearts in athletes?
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Echocardiography and pathology of left ventricular "false tendons".
The anatomic incidence of left ventricular false tendons has been determined in 100 hearts obtained from consecutive autopsies on patients who had a wide variety of cardiac conditions. In this series, an anomalous band was found in 34 cases. A retrospective two-dimensional (2D) echocardiographic study was able to identify false tendons in only 18 percent of cases with anatomic evidence of them, indicating 2 mm as the limit of resolution of 2D echocardiography even with appropriate projections. Finally, the histologic examination has shown false tendons to contain conduction tissue and thus it is assumed to be intracavitary radiations of the bundle of His. This last consideration introduces new physical and electrophysiologic implications.
Diagnostic endomyocardial biopsy findings in 160 consecutive patients: the Yugoslavian experience.
Percutaneous endomyocardial biopsy was performed for the diagnosis of various heart disorders in 160 consecutive patients in Belgrade, Yugoslavia. Tissue specimens were taken from the left ventricle in 150 patients and from the right ventricule in 10. To determine the clinical merit of endomyocardial biopsy, patients were divided into six groups based upon the existing clinical findings, including cardiomyopathy, myocarditis, specific heart muscle disease, alcohol-induced heart disease, major dysrhythmias, and other diagnoses. The clinical value of endomyocardial biopsy was gauged by the number of diagnoses that were histologically confirmed by the procedure. We combined the percentages of histologically suspected clinical diagnoses with those of completely changed clinical diagnoses and found that endomyocardial biopsy provided useful information in 70.6% of cases. Nonspecific histological findings were found in 25.6% of cases. The biopsy proved to be of no clinical value in only 3.8% of the cases. Although some investigators still object to the overall clinical usefulness of diagnostic endomyocardial biopsy, our findings help to underscore the value of this procedure for making an accurate diagnosis.
Assessment of neuron in congenital heart disease with heart failure.
Pathological studies in five hearts from patients with congenital heart diseases have demonstrated that the number of neurons is similar to that found in normal controls. The number of neurons has been counted in a strip of right atrial wall between the venae cavae. The hearts were selected from a wide spectrum of the population, the youngest being 5-months old and the oldest 35 years old (mean age: 12 years); all were in failure. The neuronal counts are comparable to those found in a normal population of mean age 40 years.
Age-associated changes in the number of neurons in the right atrium.
1. It has been demonstrated that chronotropic responses differ in healthy elderly subjects compared to those in younger normal adults. To evaluate the involvement of the autonomic nervous system, we determined the number of neurons in right atrial strips from six elderly individuals (aged 77 +/- 3.4 years) five of whom had died as the result of extracardiac causes, and from younger adult controls (aged 44.0 +/- 6.0 years) who had died in traffic accidents. 2. There was a significant reduction in the number of neurons of the group of hearts from the elderly (3587 +/- 445, mean +/- SEM) compared with the control group (6412 +/- 377) of five hearts from younger adults (P less than 0.001). 3. It is suggested that this decrease in the number of neurons contributes to the reduced chronotropic responses in the aged. The mechanisms responsible for the neuronal depopulation was not determined.
Anterior mesenchymal dysgenesis of the eye. Congenital hereditary endothelial dystrophy and congenital glaucoma.
The present report describes a patient with congenital glaucoma and iris hypoplasia who underwent repeated surgery to control the glaucoma. Despite these procedures, the patient's corneas opacified progressively, and bilateral penetrating keratoplasties were performed. Histopathological studies, including transmission and scanning electro microscopy of the corneal buttons, demonstrated specific changes of Descemet's membrane and the endothelium typical of congenital hereditary endothelial dystrophy (CHED). CHED has usually been considered to be a specific clinical entity that is not combined with congenital glaucoma or other significant abnormalities of the anterior segment of the eye. The present case indicates that these conditions may be combined, which is of importance when dealing with infants with congenital glaucoma and corneal opacities.