Biomedical subjects

S P Allwork

Publications and source records attributed to S P Allwork.

At least 19 recordsLinked to original sources

PubMed1988

Tetralogy of Fallot: the centenary of the name. A new translation of the first of Fallot's papers.

1988 marks the centenary of the cognomen "tetralogy of Fallot". Fallot's works are often quoted and translated without mentioning that it was he who applied the noun "tetralogy" to the malformation. This new translation shows that his contribution to the morbid anatomy was not great, but he was unknowningly responsible for providing a unifying concept and a name for the commonest of all cyanotic congenital heart defects.

History, 19th Century↗

PubMed1988

The pathology of mitral papillary muscles in mitral regurgitation associated with discrete subaortic stenosis.

Two patients needed mitral valve replacement for severe mitral regurgitation after surgical relief of subaortic stenosis. A third, much older patient (who died) also had mitral regurgitation after surgery to relieve subaortic stenosis and to close a ventricular septal defect. All the mitral valves showed both macroscopic and microscopic abnormalities, the latter being characterized by myocytolysis, vasculitis, and fibrosis. The severity of these abnormalities was inversely proportional to the age of the patient. The findings were compared with those (surgical and necropsy specimens) of five patients with congenital "left-sided" anomalies (group 1) and five with "right-sided" lesions (group 2). Coagulation necrosis and ischemic changes were observed in both of the control groups, but none demonstrated the combination of features observed in the patients with subaortic stenosis. The observation of myocytolysis, vasculitis, and fibrosis suggests that there may be a pathologic substrate for mitral valve malfunction in patients, especially very young ones, with subaortic stenosis.

Adult↗

PubMed1987

The applied anatomy of the arterial blood supply to the heart in man.

The applied anatomy of the coronary arterial and collateral circulations has been reviewed together with some of the more important variants of origin, branching and disposition. There is a very wide range of variability among coronary artery patterns, and some of them can of themselves give rise to illness and even death. Others may exacerbate acquired disease. The increasing use of coronary arteriography and other forms of imaging will continue to reveal hitherto undescribed variants, while the study of coronary artery disease, so common in the Western world, will eventually elucidate the natural history of the coronary collateral circulation.

Aged↗

PubMed1986

The anatomical basis of infection of the aortic root.

Although images of large abscess cavities in the aortic root in the presence of infection may be obtained by echocardiography or angiocardiography, discrete cavitations and paravalvar leaks, especially small ones, tend to remain unrecognized. Furthermore the abscesses themselves and their extent are often difficult to locate at operation, and it is this difficulty in delineating paravalvar foci of destruction which remains a major surgical challenge in aortic infections. The inability of current imaging techniques to elucidate this problem is compounded by the limited access which aortotomy gives to the aortic root. In the case of prosthetic valve endocarditis, the aortic root is often distorted, this distortion is greater where more than one prosthetic valve has been used, so that identification of septic areas and abscess cavities may further be obfuscated. Five necropsy specimens of normal hearts and 10 with infective endocarditis of either natural or prosthetic valves in either aortic or atrioventricular position were studied to elucidate the anatomy of the aortic root and to identify sites of potential abscess formation and of rupture.

Adult↗

PubMed1986

Usefulness of the phenomenon of histofluorescence in the identification of early myocardial necrosis.

To evaluate the histological phenomenon of fluorescence of necrotic myocardium in ultraviolet light a prospective study of fatal myocardial infarction with accurate clinical and biochemical correlation was made. To test the morphological characteristics and specificity of the technique experimental infarctions were induced surgically in sheep and pigs and acute ischaemia and infarction induced by catheter in intact dogs. Fluorescence was visible within five minutes of the injury in routinely stained sections and persisted for as long as cellular debris was identifiable. It was independent of autolysis, optimal fixation, prolonged storage, and special stains. Although the fluorescence was associated with hypereosinophilia in stained sections, necrotic myocardium also fluoresced in unstained ones, demonstrating primary or autofluorescence. Fluorescence microscopy is a useful adjunct to the histological identification of early myocardial necrosis and of scattered or focal necrosis especially in the absence of myocardial infarction.

Adolescent↗

PubMed1985

Failure of experimental atherosclerosis to sensitize coronary arteries to spasm in hypercholesterolemic rabbits.

Since hypercholesterolemia sensitizes isolated rabbit coronary arteries to vasoconstrictor stimuli, we assessed the possibility of reproducing occlusive coronary spasm both in vitro and in vivo in atherosclerotic rabbits. In Langendorff-perfused hearts from nine atherosclerotic rabbits (2% cholesterol diet for 18 weeks), despite a threefold increase of cholesterol concentration in the coronary wall compared with nine control rabbits, ergonovine and serotonin did not produce any increase of coronary vascular resistances; the increase produced by pitressin was significantly less in atherosclerotic than in normal hearts (56 +/- 13% vs 138 +/- 28%, p less than 0.05, respectively), whereas that produced by phenylephrine was similar (10.1 +/- 1.8% vs 8.5 +/- 2.4%, p = n.s.). In eight other unanesthetized rabbits we recorded the ECG during ergonovine administration (0.05 mg/kg) and during hypothalamic stimulation before and at regular intervals during the 2% cholesterol diet; rabbits survived for periods ranging from 1 to 22 weeks (mean 9.6 weeks). Only one animal had ST depression during episodes of marked tachycardia; no ischemic ECG changes were ever observed in the other rabbits despite the diffuse subintimal coronary deposition of cholesterol found postmortem. Thus, in atherosclerotic rabbits with chronic marked hypercholesterolemia, coronary arteries do not develop occlusive coronary spasm as observed in patients with variant angina.

Animals↗

PubMed1983

Longterm effects of cryosurgery in the sheep heart.

This study concerns the longterm effects of both epicardial and endocardial cryosurgery with particular reference to the coronary arteries. Sheep were subjected to epicardial cryosurgery without cardiopulmonary bypass, and to endocardial application with bypass. In both groups the heart was kept beating throughout the operation. Neither cardioplegia nor aortic cross-clamping was used. In the first group applications were made for 5 min directly over or adjacent to a major branch of the left coronary artery. In the second, the cryoprobe was applied for 5 min or until atrioventricular dissociation occurred. No sheep developed late arrhythmias or evidence of myocardial ischaemia. Only minimal arterial changes were observed and all the major coronary arteries remained widely patent. Cryothermia to the heart produced a small discrete lesion without complication. Bright fluorescence of necrotic myocytes was observed in all the immature lesions when sections stained with haematoxylin and eosin were examined under ultraviolet light. This vivid fluorescence clearly delineated the extent of the lesions and persisted while cytoplasmic elements remained. Our results indicate that cryosurgery provides a safe and permanent technique for the surgical treatment of arrhythmias in man, and may safely be used even in proximity to the coronary arteries. Cardioplegia is contraindicated.

Animals↗

PubMed1983

Late sudden death after repair of tetralogy of Fallot: a clinicopathologic study.

Retrospective analysis was performed to determine the likely cause of death in six patients who died suddenly 1-9 years after repair of tetralogy of Fallot. The integrity of the atrioventricular conduction system and myocardium was examined in three hearts at necropsy. Two of three patients who complained of palpitation or syncope had frequent premature ventricular complexes on routine ECGs. All the patients had complete right bundle branch block and one had left-axis deviation after repair. Postoperative cardiac catheterization (four patients) showed no residual ventricular septal defects, but right ventricular pressure was elevated in all. At necropsy, the atrioventricular conduction tissue was related to the margin of perimembranous ventricular septal defect in two patients, but was well posterior in one patient with an infundibular muscular defect. Histologic examination showed that in all cases the atrioventricular node, atrioventricular bundle and left bundle branch were undamaged. There was, however, extensive fibrosis of the right ventricular myocardium in the ventriculotomy site (three patients), septum (one patient) and outflow tract (one patient). These clinical and necropsy findings suggest that ventricular arrhythmia rather than atrioventricular block was responsible for sudden death in these patients after repair of tetralogy of Fallot.

Adolescent↗

PubMed1982

Anatomical-embryological correlates in atrioventricular septal defect.

Recent embryological studies have supported the consideration that the ventricular septum is multifocal in origin. These data have also provided excellent correlation of the morphology of malformed hearts with their embryology. In particular, atrioventricular septal defect correlates accurately with these observations on ventricular septation. Many of the names given to atrioventricular septal defect (for example ostium primum, persistent atrioventricular canal, endocardial cushion defect) indicate attempts at correlating the anatomy with embryology. None of these has been very convincing. In the light of this uncertainty, this review considers briefly the anatomy of the malformation and its ontogeny, and presents a hypothesis of the development of atrioventricular septal defect. Although there is almost always a communication above the atrioventricular valves, the malformation lies in the ventricular, not the atrial septum. Hearts with inlet septal defect without interatrial communication represent one end of the spectrum of anomalies, and those with common atrioventricular orifice, in which Fallot's tetralogy or single outlet heart may be associated, mark the other end. The outflow tract malformations are not randomly associated, but are points in a huge range of cardiac malformations.

Heart Septal Defects↗

PubMed1981

Surgical anatomy of tetralogy of Fallot.

On the basis of previous experience, we have analyzed the anatomy of a series of 53 hearts catalogued as having tetralogy of Fallot in the museum of the Children's Hospital of Pittsburgh. All hearts had a ventricular septal defect, aortic overriding, infundibular pulmonary obstruction, and right ventricular hypertrophy. None of the hearts had been operated upon during life. We paid particular attention to features of surgical importance. Thus the ventricular septal defect was found to be of variable form. It was perimembranous in 42 hearts. In 11 hearts it had entirely muscular rims and in the remaining heart it was roofed by the conjoined aortic and pulmonary valve rings (subarterial). From our previous histologic experience, it was evident that this varying morphology significantly affected the surgical anatomy of the atrioventricular conduction tissues. We endeavored to display this disposition as might be viewed by the surgeon. The degree of aortic override was variable, the aortic valve being connected by 15% to 95% to the right ventricle. In 17 hearts more than half the aortic valve was attached to right ventricular musculature. The nature of the infundibular obstruction also varied markedly. In all cases (except the one with absent infundibular septum) the infundibular septum was deviated in cephalad and anterior direction so as to produce obstruction. In the majority of hearts further anatomic structures also contributed to the obstruction. In some hearts there was hypertrophy of the infundibular septum, particularly at its junction with the trabecular septum. In others there was hypertrophy of the trabecula septomarginalis, and in many hearts there was hypertrophy of additional anterior infundibular trabeculations. The pulmonary valve was the narrowest point of the outflow tract in only six hearts, but in many of the others, it was abnormal. The results emphasize that while hearts may exhibit the classical features of tetralogy of Fallot, there is usually considerable individual variation in each of these features which is of major surgical significance.

Cardiomyopathy, Hypertrophic↗

PubMed1980

The angiographic anatomy of the coronary arteries.

The angiographic anatomy of the coronary arteries is described and illustrated by three corrosion casts of normal human hearts, photographed in projections comparable to those used in coronary arteriograms. They are accompanied by matched normal coronary arteriograms. The study of casts of the heart and of the coronary arteries in particular facilitates understanding of the radiographic projections commonly employed in coronary arteriography.

Coronary Angiography↗

PubMed1979

Maladie du Roger 1879: a new translation for the centenary.

A new translation of Roger's description of the clinical and anatomical findings in uncomplicated small VSD is presented. Reappraisal of Roger's observations in the light of our present understanding confirms that only our attitudes change; diseases remain the same.

Child↗

PubMed1979

Developmental anatomy of the membranous part of the ventricular septum in the human heart.

The anatomy of the membranous part of the ventricular septum is described in 25 hearts from patients ranging in age from 15 weeks of gestation to the ninth decade of adult life. Both atrioventricular and interventricular components were recognised in all the adult subjects, and the atrioventricular component was evident in all 25. The interventricular membranous septum was present in only 1 of the fetal hearts and 4 of the infant subjects. We consider that these findings indicate that the transformation of the membranous septum into atrioventricular and interventricular components occurs in the late fetal and early postnatal period rather than during closure of the embryonic interventricular foramen. It is associated with the liberation of the medial leaflet of the tricuspid valve from the muscular ventricular septum.

Adolescent↗

PubMed1979

The spectrum of Ebstein's anomaly of the tricuspid valve.

The structure of the tricuspid valve in 14 cases of Ebstein's malformation is described and compared with that in the normal heart. The anomalous hearts showed a spectrum of malformation, varying from minimal displacement of the adjacent parts of the septal and inferior leaflets of the tricuspid valve to presence of an imperforate membrane or muscle shelf between the inlet and trabecular zones of the right ventricle. In "typical" Ebstein's anomaly the anterosuperior leaflet was abnormally attached so as to partially obstruct the route from right atrium to distal right ventricle, the communication between these chambers being between the abnormally attached leaflet and its malformed neighbors. In two hearts, a muscular shelf produced stenosis between inlet and trabecular portions, but a competent valve was produced at this site, the atrialized part of the right ventricle being of normal thickness. The significance of these findings is considered with regard to possible methods of repair. Description of the anomaly is facilitated by considering the right ventricle as possessing inlet, trabecular, and outlet portions. The essence of the anomaly is displacement of the tricuspid orifice to the junction of the inlet and trabecular ventricular zones.

Ebstein Anomaly↗

PubMed1977

Left juxtaposition of the auricles with l-position of the aorta. Report of 6 cases.

Six hearts are described in which juxtaposition of the auricles to the left of the great arteries (left juxtaposition) was associated with l-postion of the aorta. Atrial anatomy was abnormal but constant; the os of the right auricle occupied the expected site of the atrial septum, producing posterior and inferior desplacement of this structure. This is of importance since the os could be mistaken for a defect of the atrial septum, while the displacement of actual defects is of significance to any intended catheterisation procedure including atrial septostomy. Five of the hearts showed atrioventricular concordance while the other specimen was an example of primitive ventricle with a right-sided outlet chamber. The ventriculoarterial connection in this latter case was normal, with l-malposition (anatomically corrected malposition). Ventriculoarterial connections in the other hearts were transposition in 3, single aortic trunk with pulmonary atresia in 1, and an intermediate between double outlet right ventricle and transposition in the other. These cases confirm the observation that juxtaposition of the auricles is associated with severe cyanotic congenital heart disease.

Adolescent↗

PubMed1976

Congenitally corrected transposition of the great arteries: morphologic study of 32 cases.

The detailed anatomy of the heart is described in 32 autopsy cases of congenitally corrected transposition of the great arteries.Tis condition is defined as the combination of atrioventricular (A-V) discordance and transposition of the great arteries. Examples of primitive (single) ventricle with "inverted" (that is, left-sided in situs solitus) outlet chamber are excluded. Six hearts with A-V discordance and pulmonary atresia are described in an appendix. In 29 cases of corrected transposition the heart was in situs solitus; in 3 it was in situs inversus totalis. Only 5 of these 32 hearts had no potential for intracardiac shunting. Anomalies of the tricuspid valve (91 percent of cases), ventricular septal defect (78 percent) and pulmonary outflow tract obstruction (44 percent) occurred with sufficient frequency to be considered part of the basic malformation and are described in detail. The precise anatomy and disposition of the A-V valve tension apparatus, the coronary arteries and the conducting tissues are described with special reference to possible surgical approaches for repair of the anomalies. In two hearts with situs solitus the aortic valve was right-sided with respect to the pulmonary valve. This finding is important for both diagnosis and nomenclature.

Autopsy↗

PubMed1976

Angiographic anatomy of the right heart.

Casts of human hearts were prepared and photographed to illustrate the anatomy of the right heart chambers and ventricular septum. The casts were used to illustrate the anatomy of certain common pathological abnormalities of the ventricular septum and the appearances compared to angiocardiograms.

Angiography↗

PubMed1976

Surface ultrastructure of silicone rubber aortic valve poppetts after long-term implantation. A scanning electron microscope study of four poppets.

The surface ultrastructure, demonstrated by scanning electron microscopy, is described in four implanted Silastic aortic valve poppets. Ball variance was discovered at necropsy in two patients and clinically in one in whom the poppet was replaced. The fourth patient underwent reoperation, but ball variance was neither suspected nor found. All four poppets were densely coated with biological debris and microthrombi. The 'coat' was soluble in a weak solution of sodium hydroxide. The true Silastic surface beneath the coat was little altered compared with unimplanted poppets, even after 10 years' implantation.

Adult↗