Congenital abnormalities of the aortic arch: MR imaging

Thirty-four patients, 1 month to 63 years old, with known or suspected congenital abnormalities of the aortic arch underwent magnetic resonance (MR) imaging. Sixteen patients were studied retrospectively, 18 prospectively. In all retrospective studies, the aortic arch abnormality was seen with MR imaging. In the prospective studies, MR imaging enabled diagnosis in 15 of 18 (83%) patients. Twenty-nine of 34 patients underwent two-dimensional echocardiography; nine were studied retrospectively, 20 prospectively. In the prospective studies, echocardiography enabled diagnosis in 13 of 20 (65%) patients. Although two-dimensional echocardiography has a high sensitivity in the detection of aortic arch abnormalities in the neonate, arch abnormalities in the neonate, its sensitivity is lower in older children, adults, and postoperative patients. The authors' experience shows that MR imaging is an important, noninvasive modality in the evaluation of older children, adults, and postoperative patients with congenital aortic arch abnormalities.

Use of in situ pericardium for surgical relief of pulmonary venous obstruction following Mustard's operation

A technique is described for relief of pulmonary venous obstruction following the Mustard procedure. The functional left atrium is enlarged by using the pericardium in situ. This is expected to allow for growth of the pericardial patch and to avoid recurrent obstructions. This technique has also been used in reoperations for systemic venous obstruction after enlargement of the systemic baffle with a patch.

Results of the Senning procedure in infants with simple and complex transposition of the great arteries

Because of interest in the arterial switch operation, recent experience with the Senning operation in patients with simple and complex transposition of the great arteries (TGA) was examined. Between 1982 and 1985, 35 patients with simple TGA (group I) and 10 patients with complex TGA (group II) underwent a Senning operation. Mean duration of follow-up was 14 months for group I and 24 months for group II. In group I, 1 patient died early and no patient died late; infrequently, right ventricular dysfunction, tricuspid regurgitation, baffle obstruction or arrhythmias occurred. In group II, no patient died early and 3 died late. In addition, many patients required prolonged digoxin therapy. Because the arterial switch operation has a high early mortality risk and an undetermined long-term morbidity and mortality risk, the Senning operation (or other venous switch operations) is considered the preferred surgical approach for simple TGA. In contrast, an arterial switch operation is performed in patients with complex TGA (without subpulmonic obstruction). Comparison of the early and late morbidity and mortality of the arterial vs the venous switch operation may be helpful in selecting the appropriate surgical approach to complex TGA.

Subaortic obstruction in complex congenital heart disease: management by proximal pulmonary artery to ascending aorta end to side anastomosis

Six patients with univentricular heart and one patient with d-transposition of the great arteries had transection of the main pulmonary artery with an end to side anastomosis of the main pulmonary artery to the ascending aorta to relieve subaortic obstruction. Two operations were performed as a palliative procedure within the first 6 months of life and five were performed as part of a definitive repair (four modified Fontan procedures and one repair of transposition of the great arteries with ventricular septal defect). There was one surgical death (14%) occurring 1 day postoperatively from low cardiac output. The remaining six patients are doing well 1 to 19 months postoperatively (mean 11.4 months). The proximal pulmonary artery to ascending aorta end to side anastomosis is an effective means of bypassing subaortic obstruction associated with complex congenital heart disease.

Antibodies to the N-terminus of human Gastrin-34 react with material in rat and ferret brain

Antibodies specific for the N-terminus of human big gastrin, or NT G34, reveal in immunohistochemistry extensive systems of nerve cell bodies and fibres in the rat and ferret brain. However, when the same antibodies were used in radioimmunoassay of rat and ferret brain tissue extracts they failed to reveal immunoreactive material. At least one of the antibodies used for radioimmunoassay could be shown to react with NT G34 in rat pyloric antral extracts. Antibodies specific for other peptides derived from progastrin failed to reveal the systems demonstrated with the N-terminal G34 antibodies. It is concluded that expression of the gastrin gene is unlikely to account for the present observations. Instead we suggest that a novel peptide with low affinity for NT G34 specific antibodies is found in rat and ferret central neurones.

Morphological and electrophysiological determination of the projections of jaw-elevator muscle spindle afferents in rats

The fluorescent compound Lucifer Yellow was injected into the somata of nine identified jaw-elevator muscle spindle afferents, located in the V mesencephalic nucleus. Reconstructions of the central course of their axons were subsequently made from serial, transverse, sections to identify sites of projection. Three sites of termination were identified on the basis of collaterals that ended in varicosities and/or boutons. All afferents projected to the V nucleus oralis and, all but one, also to the V motor nucleus. Two out of nine afferents had terminations in the supra-trigeminal nucleus, though a further four appeared to send collaterals to this area. The relative density of projection, judged by the number of collaterals supplied to each area, decreased in the order: V nucleus oralis, V motor nucleus and supra-trigeminal nucleus. The central course of the afferent axons was such that impulses from the periphery would arrive first at the V motor nucleus, then the V nucleus oralis, the supra-trigeminal nucleus, and finally the afferent somata in the V mesencephalic nucleus. In animals in which the masseter nerve was exposed in-continuity for electrical stimulation, electrophysiological recordings were made in the three areas described above to identify units that received a monosynaptic input from spindles in the masseter muscle. Criteria were formulated on the basis of the pattern of responses on stimulation of the masseter nerve, and the morphology of labelled neurones, for differentiating between afferents, interneurones, and motoneurones. In the V motor nucleus, monosynaptic excitatory post-synaptic potentials (e.p.s.p.s) were obtained in both synergist and masseter motoneurones. These were assumed to arise from a masseter muscle spindle input as the thresholds for exciting such afferents and eliciting e.p.s.p.s were similar. Some interneurones, chiefly in the V nucleus oralis, were activated at thresholds close to that of muscle spindle afferents and could also fire in response to muscle stretch. As their latencies (measured extracellularly) were similar to that of e.p.s.p.s in motoneurones, they were assumed to receive a monosynaptic muscle spindle input. However, most interneurones were activated at longer latencies (up to 7 ms) and some also fired to muscle stretch. Arguments are advanced, based on the long rise time of e.p.s.p.s recorded in some, that the majority of these may also be candidates for monosynaptic activation.(ABSTRACT TRUNCATED AT 400 WORDS)

Early and late results in the treatment of patients with pulmonary atresia and intact ventricular septum

The courses of 22 consecutive patients with pulmonary atresia and intact ventricular septum who underwent surgery between 1977 and 1984 were reviewed. This included 18 patients undergoing an initial surgical palliation, and four patients referred for a definitive procedure. A surgically oriented classification based on the degree of right ventricular hypoplasia was developed and applied. Three groups were identified and were termed the mild, moderate, and severe hypoplasia groups. Those in the mild and moderate groups had mild or moderate right ventricular and tricuspid hypoplasia with well-developed right ventricular outflow tracts and were therefore acceptable candidates for procedures to create an opening between the right ventricle and pulmonary artery. Those in the severe hypoplasia group and severe hypoplasia of the tricuspid valve, the right ventricle, and the right ventricle outflow tract so that attempts at establishing continuity with the pulmonary artery were thought to be unlikely to succeed. There were three patients with mild, 11 with moderate, and eight with severe hypoplasia. In the mild hypoplasia group, all three patients initially underwent valvotomy alone, but two required a shunt in the early postoperative period. In the moderate hypoplasia group, all patients underwent a valvotomy and received a central shunt with a snare, which allowed subsequent adjustment of pulmonary flow without thoracotomy in four patients. In the severe hypoplasia group, five patients received a shunt alone and one underwent valvotomy with atrial septectomy. This last patient represents the only early (less than 30 days) death in the series (6% mortality).(ABSTRACT TRUNCATED AT 250 WORDS)

Cholecystokinin and gastrin forms in the nervous system

Cholecystokinin octapeptide is the predominant representative of the gastrin-CCK family in the central nervous system. Other forms occur in low concentrations, or restricted locations, as do the gastrins. The pathways of biosynthetic processing can now be studied in detail, following the elucidation of the cDNA sequence for the two peptides. In the vagus both CCK and gastrin can be found. Brain stem neurons receiving an input from gastric mechanoreceptors respond to CCK-8, but most do not respond to gastrin given intravenously or intra-arterially. This system, which may well be involved in mediating the peripheral satiety effect of CCK, is therefore able to distinguish between the two peptides.

Accuracy of prospective two-dimensional echocardiographic evaluation of left ventricular outflow tract in complete transposition of the great arteries

Thirty-two consecutive infants with transposition of the great arteries (TGA) and ventricular septal defect underwent subxiphoid 2-dimensional echocardiography (2-D echo). Two independent observers prospectively evaluated each echocardiogram for the presence or absence of left ventricular (LV) outflow tract obstruction, whether outflow obstruction was dynamic or fixed, or both, and the precise anatomic type of fixed obstruction. Compared with the LV-to-pulmonary artery gradient determined at cardiac catheterization, 2-D echo yielded low false-negative (7 to 13%) and false-positive (0 to 6%) rates for diagnosing the presence or absence of LV outflow tract obstruction. Moreover, the false-negative cases were only minor errors, because the measured LV-pulmonary artery gradients proved to be less than 25 mm Hg. Compared with the long-axial oblique LV angiogram, 2-D echo yielded no false-negative results in detection of outflow tract obstruction, which was at least partly fixed. Compared with autopsy/surgical observation, 2-D echo made no significant errors in delineating the exact anatomic type of fixed obstruction. The diagnostic accuracy of 2-D echo in detecting and characterizing LV outflow tract obstruction limits the need for "routine" cardiac catheterization before repair in infants with TGA and intact ventricular septum. Furthermore, because certain types of fixed LV outflow tract obstruction are difficult for the surgeon to visualize and alleviate, precise knowledge of the anatomic type of fixed obstruction influences the choice among Rastelli, intraatrial baffle and arterial switch procedures in patients with TGA and ventricular septal defect.

Echocardiography in the neonate and young infant

The neonate and young child present unique problems in echocardiographic diagnosis because of the wide spectrum of possible abnormalities and the tendency toward multiple lesions, requiring clear visualization of all great veins and arteries as well as intracardiac structures. Performance and interpretation of echocardiograms in this age group require an extensive knowledge of the pathologic anatomy of congenital heart disease. Recognition of unusual lesions is facilitated by displaying the heart in an anatomically familiar (upright) format in order to draw from experience in angiography and pathology. The subxiphoid (subcostal) transducer position provides a flexible acoustic window for scanning the heart and great vessels in a multitude of planes, providing a general orientation for each cardiac segment. All other transducer positions are utilized to provide specific anatomic information. Although in this age group echocardiographic visualization of intracardiac anatomy is superior to other techniques, delineation of the great vessels remains its greatest limitation. Tortuous vessels may not lie in a single plane and, therefore, cannot always be displayed throughout its length by a "slice" technique such as echocardiography. In addition, limited focal range of most high frequency transducers is a continuing impediment to imaging structures in the posterior and superior mediastinum. Echocardiography provides a cost-effective means for identifying the neonate with life-threatening cardiovascular disease. It provides a complete and definitive anatomic diagnosis, in some cases eliminating the need for further procedures, while in others, improving the timing and performance of cardiac catheterization. Future studies should investigate the proper utilization of echocardiography as adjunct to or replacement of other techniques in the management of the young child.

Experience with the Fontan procedure

From 1975 to the present, 45 patients have undergone modifications of the Fontan procedure for complex congenital heart disease. There were 30 males and 15 females ranging in age from 2 to 38 years (mean 13 years). Primary diagnoses were tricuspid atresia in 19, univentricular heart in 24, and pulmonary atresia with intact ventricular septum in two. Right atrial-pulmonary arterial connections were performed in 32 patients, 11 with conduits (seven with valves and four without) and 21 by direct anastomosis with patch augmentation. Right atrial-right ventricular connections were made in 13 patients, six with valved conduits and seven without conduits. Follow-up ranged from 0.1 to 9 years, with a mean of 2.3 years. There were three early deaths (less than 30 days) (7%) and two late deaths (5%) in this series, all in patients with a univentricular heart. The late deaths were both related to venous hypertension. A venous assist device was used in eight patients in the immediate postoperative period and was effective in improving cardiac output and reducing fluid accumulation. Postoperative Doppler flow studies in 15 patients revealed biphasic pulmonary artery flow in all without distinction between the type of connection or the presence of a valve. Cardiac catheterization was performed in 16 patients a mean of 14 months postoperatively (range 1 to 42 months) and revealed a reduced cardiac index at rest. Exercise testing in eight patients demonstrated a marked rise in right atrial pressure with a reduced rise in the cardiac index, even in those without functional limitations. With a mean follow-up of 2.3 years, 78% of patients were in New York Heart Association Class I, 17% in Class II, and 5% in Class III. We conclude that the Fontan procedure is an excellent operation in carefully selected patients with tricuspid atresia and other forms of complex congenital heart disease.

Systemic venous and pulmonary arterial flow patterns after Fontan's procedure for tricuspid atresia or single ventricle

Despite increasing use of Fontan or modified Fontan repairs, the comparative hemodynamic efficacy of different types of connections are unresolved. Accordingly, we undertook a prospective study designed to determine postoperative flow patterns after Fontan's operation. Seven subjects had tricuspid atresia and eight had single ventricle. Ages ranged from 5 to 38 years (mean 16.4). Ten subjects had nonvalved right atrial-to-pulmonary arterial connection, and four had nonvalved right atrial-to-right ventricular communication. A valved conduit established continuity between the right atrium and right ventricle in one subject. Doppler flow profiles were recorded in the pulmonary artery and in the superior and inferior venae cavae of each. A reference electrocardiogram was used for timing purposes. In 14 patients, forward flow in the pulmonary artery was biphasic. Flow began at the end of the T wave (early ventricular diastole), peaked at or before the P wave (atrial systole), and returned to baseline by the peak of the R wave. Forward flow recommenced at the peak of the R wave (ventricular systole) and returned to baseline at the end of the T wave. Flow in the superior vena cava varied, and could not be recorded in three subjects. Between the end of the P wave and peak of the R wave (atrial systole) flow was reversed in eight, absent in three, and forward in one patient. Forward flow occurred between the peak of the R wave and the end of the T wave and was either continuous or biphasic. Fourteen patients had adequate studies of inferior vena cava flow; reversed flow during atrial systole occurred in 10 subjects.(ABSTRACT TRUNCATED AT 250 WORDS)

Immunoreactive Met-enkephalin Arg6 in rat brain, and bovine brain, gut, and adrenal

Antibodies directed against the Met-enkephalin-related hexapeptide, Met-enk Arg6, have been used in radioimmunoassays in the characterization of material in rat brain, and bovine striatum, colon, and adrenal medulla. Met-enk Lys6 reacted 0.27 relative to Met-enk Arg6, but Leu-enk Arg6 and C-terminal extensions or deletions of Met-enk Arg6 showed less than 0.02 immunoreactivity. In rat brain, the concentration of Met-enk Arg6-like immunoreactivity was less than 20 pmol X g-1 in all regions, but after trypsinization of tissue extracts there were up to 80-fold increases in immunoreactivity as a result of cleavage of C-terminally extended forms. The tryptic product eluted as Met-enk Arg6 on gel filtration. In control extracts of rat brain there were at least three immunoreactive forms of Met-enk Arg6; one eluted in the position of the hexapeptide standard on gel filtration and HPLC while the others had properties of N-terminally extended forms. In bovine striatum and colon the hexapeptide-like material predominated; but in bovine adrenal extracts, there were relatively low concentrations of the hexapeptide and, instead, the dominant immunoreactive forms corresponded to two components that were probably N-terminally extended variants. Trypsin again produced marked increases in immunoreactivity. HPLC studies indicated that Met-enk Arg6Phe7- and Met-enk Arg6Gly7Leu8-like immunoreactive peptides were important substrates in bovine brain for the production of hexapeptide immunoreactivity after trypsin. The differences in the patterns of immunoreactive forms in bovine adrenal, colon, and brain are consistent with tissue variations in the pathways of posttranslational processing of the precursor molecules.

Sensory substance P innervation of the stomach and pancreas. Demonstration of capsaicin-sensitive sensory neurons in the rat by combined immunohistochemistry and retrograde tracing

The sensory innervation of the stomach and pancreas has been identified by retrograde tracing using the fluorescent dye True Blue (Illing, Gross-Umstadt, Federal Republic of Germany), coupled with the immunohistochemical localization of substance P. Labeled cells were visualized in spinal ganglia, nodose ganglia, celiac ganglion, and dorsal motor nucleus of the vagus after injection of True Blue into both stomach and pancreas. Substance P immunoreactivity was found in 35%-50% of gastric spinal afferent neurons and in approximately 15% of pancreatic spinal afferents. In rats treated at birth with the sensory neurotoxin capsaicin there was a reduction of about 70% in True Blue-labeled cells in the spinal and nodose ganglia, and virtually complete loss of substance P in these ganglia. There was also a marked depletion of substance P-immunoreactive fibers in the pancreas, and in the submucosa of the stomach. The results suggest that the substance P-containing spinal afferents that project to the gastric submucosa are an important component of the gastric sensory innervation.

Evidence for different patterns of post-translational processing of pro-enkephalin in the bovine adrenal, colon and striatum indicated by radioimmunoassay using region-specific antisera to Met-Enk-Arg6-Phe7 and Met-Enk-Arg6-Gly7-Leu8

Specific antisera to two opioid peptides, Met-Enk-Arg6-Phe7 and Met-Enk-Arg6-Gly7-Leu8, were used in radioimmunoassay to study molecular forms in extracts of bovine adrenal, striatum and colon. The antisera to Met-Enk-Arg6-Phe7 and Met-Enk-Arg6-Gly7-Leu8 were each highly specific for the C-terminus of their respective haptens and showed less than 1% cross-reactivity with related enkephalins and their variants. In adrenal extracts, gel filtration on Sephadex G-50 indicated N-terminally extended forms of Met-Enk-Arg6-Phe7 and Met-Enk-Arg6-Gly7-Leu8 as the predominating immunoreactive species, whereas in the striatum and colon the main immunoreactive forms were compatible with the hepta- and octapeptides. The results suggest different patterns of post-translational processing of precursors in the adrenal medulla compared with striatal and colonic neurones.

Moyamoya disease and cerebral hemorrhage

A case with the clinical, x-ray, and computed tomographic features characteristic of moyamoya disease and a large intracerebral hemorrhage is presented. The recent literature is reviewed, noting current concepts in diagnosis, treatment, and prognosis of this curious disorder. Although much has been written about moyamoya disease and its treatment, it remains a very unusual disorder, particularly in a middle-aged white adult.

Mechanisms of cardiac supersensitivity to sympathomimetic amines

Supersensitivity of the beta-adrenoceptor-mediated positive inotropic and chronotropic responses of the heart to sympathomimetic amines is considered. The various types of supersensitivity of both pre- and post-synaptic origins are described and the possible mechanisms involved are discussed. Emphasis is given to the supersensitivity that arises from depletion of sympathetic catecholamine stores by reserpine and 6-hydroxydopamine. Results are presented which indicate that in both cases the supersensitivity develops slowly, is specific for the beta-adrenoceptor and is not associated with an increase in affinity of agonists for the receptor. Radioligand binding data is presented to show that there is no increase in the total number of beta-adrenoceptor binding sites in membrane fractions from ventricular homogenates of animals receiving reserpine. A review of the literature on binding studies indicates two opposing views with respect to the effects of reserpine on beta-adrenoceptor binding sites, one showing no change and the other showing an increase in total binding sites. Limited studies in the literature show that 6-hydroxydopamine may increase the number of sites. Binding data therefore remains inconclusive and must be interpreted with caution. The relationship between the development of depletion-induced supersensitivity and the innervation of the tissue and its receptor type is discussed.

Cancer of the mouth in an isolated community--the results of treatment

A survey is presented of all known cases of cancer of the mouth in a population of nearly half a million in a relatively isolated part of Yorkshire, with the results of treatment of squamous carcinoma, adeno-carcinoma, lympho-sarcoma, malignant tumours of odontogenic origin and sarcomas.

Extrinsic innervation of the rat pancreas: demonstration of vagal sensory neurones in the rat by retrograde tracing

The extrinsic innervation of the rat pancreas was examined using retrograde tracing with the fluorescent dye True Blue. Retrogradely-labelled cell bodies were seen bilaterally in the nodose ganglia, and in the spinal ganglia at levels T6-L2. Labelled cells were also seen in the dorsal motor nucleus of the vagus, the nucleus ambiguus and the coeliac ganglion. Our results provide new and direct evidence for a vagal sensory innervation of the pancreas.

Sensory substance P-innervation of the urinary bladder: possible site of action of capsaicin in causing urine retention in rats

In rats treated neonatally with capsaicin there is, in later life, a tendency tendency towards urine retention. Since capsaicin is known to cause irreversible loss of certain primary sensory neurons, notably those containing substance P, we have studied the sensory innervation of the bladder in capsaicin-treated and control rats using retrograde tracing methods and immunohistochemistry; in addition, the motor function of the bladder was assessed in in vitro experiments, using electrical field stimulation. Five days after injection of the fluorescent tracer True Blue into the wall of the bladder, numerous labelled cells were identified in dorsal root ganglia T13, L1, L2, L6, and S1 and smaller numbers of cells were found in T12 and L3. In capsaicin-treated rats the numbers of labelled cells were reduced by over 50% in L1, L6 and S1. In control rats, 10-16% of True Blue labelled cells also contained substance P as demonstrated by indirect immunofluorescence, but in capsaicin-treated rats substance P cells were virtually absent. In in vitro studies, contractions of the detrusor muscle to electrical field stimulation, both before and after atropine, were similar in control and capsaicin-treated rats. We suggest that capsaicin causes urine retention in rats due to an impairment of sensory transmission from the bladder (that could involve substance P) and a consequent failure in the normal micturition reflexes.

Immunohistochemical studies of FMRF-amide-like immunoreactivity in rat brain

The anatomical distribution of neuronal perikarya and nerve fibres containing FMRF-amide-like immunoreactivity in the brain, spinal cord and pituitary of the rat has been studied by immunohistochemistry. In animals pretreated with colchicine, the highest concentration of nerve cell bodies occurred in hypothalamic nuclei. Cells were also present in the cortex, striatum, septum, thalamus and in the brainstem. Beaded nerve fibres were abundant in the septum, nucleus of the striae terminalis, hypothalamus, medial regions of the thalamus, the parabrachial nucleus, the ventrolateral medulla, the substantia gelatinosa of the spinal trigeminal nucleus and the dorsal horn of the spinal cord. Fibres were also present in the cortex, striatum, amygdala, pons, ventral spinal cord and the neural lobe of the pituitary. The localization was specific in that preabsorbtion of the antisera with FMRF-amide, but not structurally related molecules such as Met-Enk-Arg6Phe7, APP or BPP, completely abolished the localization. The mammalian counterparts of FMRF-amide may have a neurotransmitter or neuromodulatory role.