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R H Anderson

Publications and source records attributed to R H Anderson.

At least 271 records · Page 15Linked to original sources
PubMed1991

Atrial morphologic features in tricuspid atresia.

We studied the atrial morphology in 110 hearts removed at autopsy from patients with tricuspid atresia. Ten of the patients had had a Fontan operation. We compared the findings in these hearts with those in 30 normal hearts. Prominent eustachian valves were common (40%). The tricuspid "dimple," present in 33 of 100 specimens, denoted the membranous atrioventricular septum and was never related to the right ventricle. Most interatrial communications (85/100) were nonobstructive. A minority of patients with obstructive interatrial communications (13/100 = small, 2/100 = severely obstructive) would be expected to benefit from balloon atrial septostomy early in life. Right atrial hypertrophy was greatest in specimens with restrictive interatrial communications (severely obstructive = 3.2 +/- 0.3 mm, small = 2.1 +/- 0.6 mm) and in those that had been subjected to a Fontan operation (3.2 +/- 0.7 mm), but thickness was also increased in hearts with nonobstructive interatrial communications (1.6 +/- 0.5 mm) compared with normal hearts (1.1 +/- 0.2 mm; p less than 0.001 versus all groups). Of the patients in the series, 11 of 100 had left juxtaposition of the atrial appendages, which may have important implications for the Fontan operation.

Adolescent↗
PubMed1991

Morphologic-echocardiographic correlates of Ebstein's malformation.

The cross-sectional echocardiographic findings were analysed retrospectively in 26 patients with Ebstein's malformation in the light of studies of autopsied specimens from different patients showing this lesion. The salient anatomical feature in diagnosis is the finding of the hinge point of the septal and mural leaflets of the valve within the inlet component of the right ventricle rather than at the atrioventricular junction. The other important feature is the nature of the distal attachment of the leaflets, particularly the anterosuperior one, which can either be in focal or linear fashion. The hinge point of the septal leaflet was noted echocardiographically to be displaced in 19 patients but, significantly, the leaflet was absent in the other seven. Also significant was that the hinge point of the mural leaflet at the crux had been visualized in only 15 of the patients. The anterosuperior leaflet had a distal linear attachment in 20 of the patients, with the anteroseptal commissure becoming a keyhole in six of these through which blood passed to the functional right ventricle. The valve remained a competent structure, even though closing at the junction of atrialized and functional components of the right ventricle rather than at the atrioventricular junction. Cross-sectional echocardiography is the technique of choice with which to display the salient morphological features of Ebstein's malformation.

Adolescent↗
PubMed1991

The surgical anatomy of double-outlet right ventricle with concordant atrioventricular connection and noncommitted ventricular septal defect.

In describing hearts with double-outlet right ventricle, we have had problems with how best to use the term noncommitted as applied to the ventricular septal defect. We reviewed, therefore, 63 hearts with double-outlet right ventricle in the setting of usual atrial arrangement and a concordant atrioventricular connection. From these, 18 hearts with potentially noncommitted defects were identified and studied in detail. The defect was unequivocally remote from the ventricular outflow tracts in 16 of these hearts, being perimembranous with excavation to open into the inlet of the right ventricle in 12, two of these also having straddling of an atrioventricular valve. One heart had a muscular defect situated in the inlet part of the muscular septum, whereas the defect was the ventricular component of an atrioventricular septal defect in the other three. In the remaining two hearts the defect was anatomically juxtaposed to a subarterial outlet. The pathway to the outflow tract, however, was obstructed by leaflets of a straddling valve. Our study shows, therefore, the need to distinguish between anatomic "commitment" of the defect from the problems in terms of commitment that may confront the surgeon in the operating room. Not only does the distance between the interventricular communication and one of the subarterial outflow tract need to be assessed (the anatomic commitment), but also the presence and nature of any intervening extraneous tissues (the surgical commitment) requires assessment.

Double Outlet Right Ventricle↗
PubMed1991

Critical aortic stenosis in early infancy. Anatomic and echocardiographic substrates of successful open valvotomy.

To establish noninvasive criteria by which to manage infants with critical aortic stenosis, we examined 20 heart specimens from infants under 3 months of age and reviewed the clinical course and real time echocardiograms of 20 patients in the same age group. All 20 infants underwent open valvotomy, and in five cases both echocardiographic and postmortem measurements were available for the same heart. The anatomic specimens showed a spectrum of valvular, ventricular, and vascular abnormalities that could be accurately identified by echocardiography. A small left ventricular cavity was usually associated with a narrow ventriculoarterial junction, small ascending aorta, and narrow subaortic region. In these hearts, the mitral valve had a single or grossly hypoplastic papillary muscle with short or "arcuate" tendinous cords. A dilated left ventricular cavity had wider inflow and outflow orifices, and the tension apparatus of the mitral valve was either normal or supported by hypertrophic papillary muscles, at the other end of the spectrum. The survivors (n = 15) and nonsurvivors (n = 5) of open valvotomy showed significant differences in the echocardiographic dimensions of the left ventricle (p less than 0.005), the subaortic region (p less than 0.05), the ventriculoaortic junction (p less than 0.05), the ascending aorta (p less than 0.005), and the mitral valve orifice (p less than 0.001). Moreover, the papillary muscle of the mitral valve was invariably single or hypoplastic with short tendinous cords in the early nonsurvivors. Infants with unfavorable cardiac anatomy tended to present earlier (p less than 0.05) and to have a lower systemic blood pressure (p less than 0.05), and they required prostaglandin E2 to maintain right ventricular support of the circulation through a persistent arterial duct. This study suggests that patients with a small left ventricle (echocardiographic inflow dimension less than 25 mm), a narrow ventriculoaortic junction (less than 5 mm), and a small mitral valve orifice (less than 9 mm) will not achieve a satisfactory surgical result from aortic valvotomy. Such patients should be considered for cardiac transplantation or the Norwood-type of palliation for hypoplastic left heart syndrome.

Aortic Valve↗
PubMed1991

Double-inlet ventricle presenting in infancy. I. Survival without definitive repair.

Survival before definitive operations was studied in 191 infants with double-inlet ventricle presenting before 1 year of age (1973 to 1988, median follow-up 8.5 years). The morphologic spectrum was broad, with a great prevalence of associated lesions. The actuarial survival rate before definitive repair was 57% at 1 year, 43% at 5 years, and 42% at 10 years, worse than prior reports because of the younger age at entry into our series. Analysis of univariate risk factors established that right atrial isomerism (18% of the group, relative risk 2.9), common atrioventricular orifice (42%, 2.0), pulmonary atresia (20%, 3.4), obstruction of the systemic outflow tract (18%, 2.5), and extracardiac anomalous pulmonary venous connection (13%, 3.1) were strongly associated with poorer survival. Pulmonary stenosis (40%, 0.35), balanced pulmonary blood flow (9%, 0.40), and presentation at an older age (3%, 0.42 to 0.18) were beneficial (p less than 0.05 to 0.0001). Multivariate analysis allowed the creation of patient-specific curves for prediction of survival for different anatomic and physiologic variants of double-inlet ventricle. A simple additive index was then derived from the multivariate Cox coefficients to enable stratification of risk for these morphologic subgroups of patients and so assist in the making of clinical decisions in infancy.

Follow-Up Studies↗
PubMed1991

Double-inlet ventricle presenting in infancy. III. Outcome and potential for definitive repair.

The fate of 191 infants with double-inlet ventricle was studied to determine the influence of morphologic characteristics at presentation and subsequent management on the potential for, and timing of, definitive repair by the Fontan operation or ventricular septation. At presentation, 136 patients (71%) were potential candidates for a Fontan procedure. Actuarial survival was better than for those deemed unsuitable for either definitive option (n = 55; 68% versus 28% at 1 year; p less than 0.001), but still, only 78 patients (57%) were known to be alive and suitable candidates at 2 years of age. This was largely due to death after presentation with low cardiac output (n = 19) and at palliative operation (20 of 98 surgically treated patients). The adverse events of late sudden death (n = 14) and the development of new features precluding a Fontan operation (n = 18) mostly occurred before 4 years of age (n = 22). Patients requiring no operation and those who underwent a systemic-pulmonary arterial shunt fared better than those who underwent isolated banding of the pulmonary trunk (9/13 and 25/42 alive and suitable versus 14/33; p less than 0.05), and than those who required aortic arch repair together with banding (1/12; p less than 0.01), because of the development of subaortic stenosis in the latter group. In contrast, only 43 patients (23% of all 191 patients) had morphologic features that were additionally compatible with future ventricular septation. Actuarial survival free of adverse events for these 43 patients was similar to that of the 136 patients considered suitable for a Fontan operation. Thus management in infancy must be aimed at maintaining potential for a future Fontan operation, which itself should not be delayed, for most patients, beyond 3 years of age, because of the prevalence of adverse events with increasing age.

Follow-Up Studies↗
PubMed1990

Normal variations in the relationship of the tricuspid valve to the membranous septum in the human heart.

The anatomy of the antero-septal commissure of the tricuspid valve and its relationship to the membranous part of the septum are described in 72 normal hearts from subjects ranging in age from 25 weeks gestation to 13 months. Three major patterns were found. According to whether the contiguous leaflets were fused at the commissure, joined at the circumference of the orifice, or left a gap at the commissural site, the varieties are described as undivided, annular, or gap commissure, respectively. Commissures of annular type showed further morphological varieties, as did the patterns of division of the membranous septum into its atrioventricular and interventricular components. Dominance of the atrioventricular component and/or absence of the interventricular membranous septum were encountered in 38 cases out of 72 (52%). This finding demonstrates that dominance of the atrioventricular membranous septum during fetal life and infancy is not universal. The variability noted in the morphology and position of the antero-septal commissure was not associated with other positional variations of the tricuspid valve.

Fetus↗
PubMed1990

Congenitally unguarded tricuspid orifice: its differentiation from Ebstein's malformation in association with pulmonary atresia and intact ventricular septum.

Dysplasia of the leaflets is a well-known integral part of Ebstein's malformation. It is less well-recognized that occasionally the septal leaflet may be completely absent and not simply displaced from its usual annular attachment. This may make it difficult to differentiate by echocardiography between Ebstein's malformation and the rare lesion in which the tricuspid orifice is completely devoid of leaflet tissue ("congenitally unguarded orifice"). A neonatal case is described in which a partially unguarded orifice was present in association with pulmonary atresia and intact ventricular septum but misdiagnosed as Ebstein's malformation. In addition we reviewed the morphologic features of all 46 cases of pulmonary atresia and intact septum in the Cardiopathological Collection of the Children's Hospital of Pittsburgh: 17 also had Ebstein's malformation, while three had a congenitally unguarded tricuspid orifice. We found that the differential diagnosis occurred when the right ventricle was dilated rather than being a hypoplastic cavity, as was a feature of all the cases with unguarded orifice and five of those with Ebstein's malformation. The difference between the lesions is best demonstrated by examining the mural leaflet of the valve, which is absent when the orifice is unguarded but displaced in association with Ebstein's malformation. This feature should be recognizable by cross-sectional echocardiography. We have confirmed previous studies that dilatation of the chambers of the right heart indicates a very poor prognosis in cases with pulmonary atresia and an intact ventricular septum.

Diagnosis, Differential↗
PubMed1990

Variations within the fibrous skeleton and ventricular outflow tracts in tetralogy of Fallot.

We studied 20 hearts with tetralogy of Fallot with particular reference to the morphology of the fibrous continuity between the aortic and atrioventricular valves and of the ventricular outflow tracts. The extent of valvar fibrous continuity varied with the degree of aortic override, with the extent of the perimembranous ventricular septal defect opening between the ventricular inlets, and with the development of the ventriculoinfundibular fold. This, when fused with the septomarginal trabeculation, produced discontinuity between the leaflets of the tricuspid valve and the continuous leaflets of the aortic and mitral valves, as well as a muscular posteroinferior rim to the defect. Rotation of the aortic root ranged through 119 degrees. Aortic override varied from 33% to 94%, with 35% of these hearts having more than half of the aortic circumference connected to the right ventricle. The pulmonary valves had three leaflets in 50%, two leaflets in 45%, and four leaflets in one (5%). All hearts had two main coronary arterial orifices, 45% of which were atypical in location. One heart displayed a transmural course of the left coronary artery arising from the nonfacing sinus. By measurement, the subpulmonary length was, on average, roughly 50% greater than the subaortic length, and, when the selected hearts were sectioned, much of the subpulmonary infundibulum was found to be composed of free-standing musculature rather than true outlet septum. The proportion of total right ventricular length represented by the infundibulum was 0.31 +/- 0.07, confirming that, compared with that of normal hearts, the narrowed infundibulum in tetralogy is longer rather than shorter.

Aortic Valve↗
PubMed1990

Unusual opening of coronary sinus in atrioventricular septal defects.

The coronary sinus is an important landmark for the position of the atrial component of the atrioventricular conduction axis and, thus, assumes special relevance to the surgeon in the operating room. We describe here 2 patients with atrioventricular septal defect characterized by an unusual termination of the coronary sinus within the left atrium. We discuss the potential importance of this finding to the disposition and surgical avoidance of the conduction tissues.

Abnormalities, Multiple↗
PubMed1990

Magnetic resonance imaging of the great arteries in infants.

Sixty infants, aged 1-48 (median 8) weeks, with suspected congenital heart disease underwent a morphological evaluation of the great arteries using magnetic resonance imaging at 1.5 Tesla. Cross-sectional echocardiography was performed in all infants, angiography in 33 and surgery in 44. Multiple sections, 5 mm thick and gated to the patients' electrocardiogram were acquired in standard and oblique imaging planes. Ventriculo-arterial connexions were correctly identified in 54 infants (6 did not have intracardiac imaging performed) and an accurate description of the relationships of the great arteries was made in all. Magnetic resonance imaging clearly demonstrated normal and hypoplastic pulmonary arteries to the level of the first hilar branches and was better than echocardiography at confirming the presence or absence of central intrapericardial pulmonary arteries in 4 infants with pulmonary atresia. All parts of the thoracic aorta were accurately demonstrated and, in 23 infants with clinical suspicion of aortic coarctation, magnetic resonance images provided more information than echocardiography. Magnetic resonance imaging accurately demonstrates great arteries non-invasively supplementing echocardiographic and angiographic findings. In many cases, it replaces the need for invasive investigations.

Aorta, Thoracic↗
PubMed1990

Is banding of the pulmonary trunk obsolete for infants with tricuspid atresia and double inlet ventricle with a discordant ventriculoarterial connection? Role of aortic arch obstruction and subaortic stenosis.

Banding the pulmonary trunk may exacerbate or promote the development of subaortic stenosis in patients with double inlet ventricle or tricuspid atresia with a dominant left ventricle and discordant ventriculoarterial connection and, therefore, may be an inappropriate palliative procedure for such patients. To examine this possibility, 102 consecutive infants were studied who presented with this anatomy between 1972 and 1987. Obstruction of the aortic arch was present in 52 patients. In 28 patients (17 with aortic arch obstruction), subaortic stenosis was already apparent at presentation. Of the remaining 74 patients, 19 received no palliative surgery and 55 underwent banding of the pulmonary trunk either with (n = 22) or without (n = 33) aortic arch repair. Outcome was significantly worse in patients with associated aortic arch obstruction. All such patients either died or developed subaortic stenosis by 3 years of age (survival free of subaortic stenosis 0 of 22 versus 22 of 33 for patients with isolated banding of the pulmonary trunk, p less than 0.001). After isolated banding, there was a lower ratio of the ventricular septal defect to ascending aorta diameters at presentation in the patients who developed subaortic stenosis than in the patients who did not (0.60 +/- 0.08 versus 1.03 +/- 0.15, p less than 0.001). Of the latter, 18 (95%) of 19 patients fulfilled criteria for a Fontan procedure at recatheterization. Thus, the presence of aortic arch obstruction is associated with rapid development of subaortic stenosis after banding of the pulmonary trunk. Alternative initial surgery, even though high risk, may be indicated. In the absence of such obstruction, banding the pulmonary trunk can be performed at reasonable risk and, provided that the ventricular septal defect is of adequate size, satisfactorily prepares most patients for a later Fontan procedure.

Aortic Arch Syndromes↗
PubMed1990

The potential for subpulmonary obstruction in complete transposition after the arterial switch procedure. An anatomic study.

Increasing experience with the arterial switch procedure has revealed that, in some instances, obstruction of the newly created sub-pulmonary outflow tract is a major problem. In this study, we examined the right ventricular outflow tract in 51 specimens of complete transposition, 18 of which were associated with a ventricular septal defect. We focussed our attention on the musculature which made up the outflow region and considered variations from that found in the normal right ventricle. Our gross observations showed differences in morphology which produced a sharper angulation between inflow and outflow when compared to the normal. Discrete outflow obstruction was found in 11 hearts (8 with ventricular septal defect and 3 with an intact ventricular septum). The obstruction was due to deviation of the outlet septum in 5, and anomalous muscle bundle in 1, hypertrophy of septomarginal and septoparietal trabeculations in 3 and circumferential infundibular hypertrophy in 2 hearts. Coexisting obstruction of the left ventricular outflow was present in 3 hearts. The anatomical substrates of discrete obstruction should be identified by preoperative cross-sectional echocardiography and/or angiography. Modifications in surgical techniques or radical resection of the obstructing musculature could then be performed to avoid the problem of subpulmonary obstruction after the arterial switch procedure.

Heart Septal Defects, Ventricular↗
PubMed1990

Coronary artery diameters in the heart with complete transposition of the great vessels.

The use of echocardiography established values for dimensions of normal coronary arteries in the setting of the heart with complete transposition (concordant atrioventricular and discordant ventriculoarterial connections) was evaluated. The diameters of the proximal coronary arteries measured at autopsy in 20 patients with complete transposition who had or had not undergone surgery were directly comparable with values determined in normal hearts by two-dimensional echocardiography. The values showed a linear increase with age, weight and length of the patients despite different branching patterns of the coronary arteries. Although there was right ventricular hypertrophy in all cases, the orifices of the right and left coronary arteries did not show any significant difference in diameter. Histologic examination and measurement of the arteries also revealed findings comparable with those in normal hearts. These findings suggest a relatively constant developmental pattern of the proximal coronary arteries despite different hemodynamics between the concordantly connected heart and the heart with complete transposition. In contrast, the functional significance of the stiff and slitlike orifices of the coronary arteries and their comparatively small diameters in relation to the ventricular wall thickness in four hearts studied after the arterial switch procedure for transposition merit further investigation.

Age Factors↗
PubMed1990

Hepatic venous connection to a persistent inferior caval vein in left isomerism.

In 22 cases of left atrial isomerism studied at the Brompton Hospital, four cases were found to have an unusual arrangement of the abdominal vessels. There was persistence of an inferior caval vein, partially anomalous hepatic venous connection and additional continuation of part of the venous return from the lower body through the azygos venous system. This venous pattern had surgical implications in our index case, since redirection of the inferior caval venous return was necessary.

Female↗