Thymoma epithelial cells secrete thymic hormone but do not express class II antigens of the major histocompatibility complex.

17 thymomas were studied by indirect immunofluorescence for the presence of thymic hormones and antigens of the major histocompatibility complex (MHC). The thymoma epithelial cells (specifically identified by their keratin content) contained thymic hormones (thymulin and thymosin alpha 1), a finding corroborated by the observation of elevated thymulin serum levels. In contrast with normal or hyperplastic thymuses, thymoma epithelial cells did not express HLA-DR and HLA-DC antigens as assessed by immunofluorescence as well as immunoblot analyses. Conversely, MHC class I antigens (HLA-ABC) were normally expressed. Thus, we conclude that thymoma epithelial cells are endocrinologically active but are defective for the expression of some MHC products (class II molecules) known to play an essential role in intrathymic T cell differentiation.

Evidence of enhanced recombinant interleukin-2 sensitivity in thymic lymphocytes from patients with myasthenia gravis: possible role in autoimmune pathogenesis.

We evaluated the activation state of thymic lymphocytes in patients with myasthenia gravis (MG) by cytofluorographic analysis of CD25 expression and by testing their sensitivity to recombinant interleukin-2 (rIL-2) in the absence of any known previous stimulation. We detected no phenotypic signs of activation in fresh MG thymic lymphocyte suspensions, while functional signs of activation were reflected in a significantly higher sensitivity to rIL-2 in MG patients than in controls. The responses to rIL-2 were time- and dose-dependent, were inhibited by a blocking anti-IL-2 receptor antibody, and were associated with an increase in CD25+ T cells in both patients and controls. The T cells with functional signs of previous activation may represent autoreactive cells involved in the autoimmune process and confirm thymus gland hyperactivity in MG. These cells could result from primary autosensitization against the thymic acetylcholine receptor (AChR)-like molecule or from altered migration of peripheral activated cells into an abnormal thymic environment. Our results also provide a clue for understanding the effect of thymectomy in myasthenia gravis.

Aortic arch anomalies in children and infants.

The authors report their experience in 150 cases of aortic arch anomalies treated surgically in children and infants. The progress achieved over the past few years through improved diagnosis and resuscitative care has made it possible to obtain good results in the vast majority of cases.

Tetralogy of Fallot with type C complete atrioventricular canal: surgical repair in three cases.

The successful repair of three consecutive cases of tetralogy of Fallot associated with complete atrioventricular canal type C is reported. The correct preoperative diagnosis was established by right and left ventriculography. Operative repair in the first two patients involved division of both hemivalves above the crest of the ventricular septal defect and closure of the septal defects with a single large Dacron patch. In the third patient, the septal defects were closed with two separate patches. The undivided hemivalves were attached to the patches by interrupted sutures placed more to the right side of the midline, so that tricuspid tissue was used to reconstitute the mitral valve. Right ventricular outflow tract obstruction was relieved by infundibulectomy, pulmonary valvulotomy, and placement of a Darcon patch on the infundibulum in Cases 1 and 3. A valved tube was used in Case 2. Six months postoperatively, the condition of the patient is satisfactory. The first patient is receiving digitalis; the second, digitalis and diuretics; and the third patient is well without treatment.

A study of the electroencephalogram during surgery with deep hypothermia and circulatory arrest in infants.

Seveteen infants (2 1/2 to 28 months old) were continuously monitored by six-channel electroencephalography (EEG) during the entire surgical procedure of open-heart repair. They were subjected to surface hypothermia supplemented by cold extracorporeal circulation (ECC) down to an average esophageal temperature of 21 degrees C., to cardiac arrest of 40 minutes average (range 19 to 62 minutes), and to ECC rewarming. Survival time of the EEG was correlated to esophageal temperature at the time of arrest. EEG reappeared an average of 26 minutes (5.30 to 50) after the strat of rewarming ECC and became strictly continuous after 44 minutes. Reappearance latency was well correlated with the duration of arrest. Potential normalization was oberved in 13 infants, but true normalization was observed in only 2 infants during the 90 to 120 minute period after ECC. By judging the EEG and by comparing this series with two previous series of moderate and deeper hypothermia in older patients, we concluded that the immediate tolerance of the brain to deep hypothermia and circulatory arrest seems no different in infants and in older patients.

Switch operation for transposition of the great arteries in neonates. A study of 120 patients.

From March 1984 to January 1987, anatomic surgical correction was performed on 110 newborn infants (2 to 23 days old, mean 7.8 +/- 3.5, standard deviation) with simple transposition of the great arteries and 10 additional neonates (7 to 30 days old, mean 17.9 +/- 8.3, standard deviation) with transposition and a large ventricular septal defect. All had preoperative catheterization. Ninety-six percent of the patients underwent balloon atrial septostomy and 90% received prostaglandin E1 infusion until the time of the operation. The anatomy of the coronary arteries according to the Yacoub classification was as follows: type A, 82 patients; type B, 5 patients; type C, 4 patients; type D, 23 patients; and type E, 6 patients. Continuous hypothermic bypass with no circulatory arrest was used for all patients except two. Myocardial protection was ensured by crystalloid cardioplegia. Coronary artery relocation was performed according to the Yacoub technique with some modifications, and pulmonary artery reconstruction was done according to the Lecompte maneuver in all patients, even when the great vessels had a side-by-side relationship. The proximal pulmonary artery was reconstructed with two circular patches for the first 10 patients and with a single large posterior patch for the last 110 patients. Tanned heterologous pericardium was used for the first 25 patients and autologous native pericardium for the last 95 patients. The perioperative mortality rates were 8.3% for the entire series and 5.4% for the last 110 patients, with no deaths in the group having transposition plus ventricular septal defect. Late death from acute myocardial infarction occurred in two patients in the second month after operation. No patient was lost to follow-up, which ranged from 2 to 46 months (mean 16 +/- 11.2, standard deviation). The follow-up included sequential noninvasive evaluations and 32 catheterizations performed 10 to 18 months postoperatively. Two patients were reoperated on for pulmonary stenosis caused by retraction of the two heterologous pericardial patches, but neither died. Six others have mild to moderate pulmonary stenosis. Two patients have trivial aortic regurgitation. None have aortic dilatation or supravalvular aortic stenosis. The 108 survivors have no cardiovascular symptoms. They all are in sinus rhythm, have normal left ventricular function, have no ischemic problems, and receive no medication.

Surgery for congenital mitral valve disease in the first year of life.

Between 1980 and 1993, 20 patients less than 1 year of age underwent operations for congenital mitral valve disease. Ten patients had congenital mitral incompetence and 10 had congenital mitral stenosis. Mean age was 6.6 +/- 3.4 months and mean weight was 5.6 +/- 1.5 kg. Atrioventricular canal defects, univentricular heart, class III/IV hypoplastic left heart syndrome, discordant atrioventricular and ventriculoarterial connections, and acquired mitral valve disease were excluded. Indications for operation were intractable heart failure or severe pulmonary hypertension, or both. Associated lesions, present in 90% of the patients, had been corrected by a previous operation in seven. In congenital mitral incompetence there was normal leaflet motion (n = 3), leaflet prolapse (n = 2), and restricted leaflet motion (n = 5). In congenital mitral stenosis anatomic abnormalities were parachute mitral valve (n = 4), typical mitral stenosis (n = 3), hammock mitral valve (n = 2), and supramitral ring (n = 1). Mitral valve repair was initially performed in 19 patients and valve replacement in one with hammock valve. Concurrent repair of associated lesions was performed in 12 patients. The operative mortality rate was zero. There were six early reoperations in five patients for mitral valve replacement (n = 4), a second repair (n = 1), and prosthetic valve thrombectomy (n = 1). One late death occurred 9 months after valve replacement. Late reoperations for mitral valve replacement (n = 2), aortic valve replacement (n = 1), mitral valve repair (n = 2), subaortic stenosis resection (n = 1), and second mitral valve replacement (n = 1) were performed in five patients. Actuarial freedom from reoperation is 58.0% +/- 11.3% (70% confidence limits 46.9% to 68.9%) at 7 years. After a mean follow-up of 67.6 +/- 42.8 months, 94% of living patients are in New York Heart Association class I. Doppler echocardiographic studies among the 13 patients with a native mitral valve show mitral incompetence of greater than moderate degree in one patient and no significant residual mitral stenosis. Overall, six patients have mitral prosthetic valves with a mean transprosthetic gradient of 6.2 +/- 3.7 mm Hg. These results show that surgical treatment for congenital mitral valve disease in the first year of life can be performed with low mortality. Valve repair is a realistic goal in about 70% of patients and possibly more with increased experience. Reoperation rate is still high and is related to complexity of mitral lesions and associated anomalies, but late functional results are encouraging.

Obstructed total anomalous pulmonary venous return. Toward neutralization of a major risk factor.

Among 57 neonates undergoing repair of total anomalous pulmonary venous return with severe pulmonary venous obstruction from 1980 through 1989, date of operation (1980 to 1984), preoperative hemodynamic instability, and failure to monitor pulmonary artery pressure postoperatively were risk factors for death. Thus, among the 30 patients having repair between 1985 and 1989, the 55-month survival rate including hospital deaths was 83%.

Surgical management of isolated multiple ventricular septal defects. Logical approach in 130 cases.

From January 1980 through September 1990, 130 children underwent surgical closure of isolated multiple ventricular septal defects (mean age 14 +/- 18 months, mean weight 7.0 +/- 4.4 kg). Sixty-one were less than 1 year of age. Sixty-one children had pulmonary protection, 51 had pulmonary artery banding, and 10 had pulmonary valve stenosis. All other patients had severe pulmonary hypertension (mean systolic pressure 75.7 +/- 20.5 mm Hg and already disabling heart failure (New York Heart Association classes III and IV). The surgical management was based on the location of the defects and the ventricular dominance that were assessed preoperatively and intraoperatively. Midtrabecular ventricular septal defects were always centered by the moderator band and were therefore divided into low trabecular, midtrabecular, and high trabecular defects. The perimembranous septum was involved in 102 patients, the trabecular in 121, the inlet septum in 12, and the infundibular septum in 9. Fifty patients had the "Swiss cheese" form of the lesion. Closure of the ventricular septal defects included Dacron patch and mattress sutures. They were always first approached through a right atriotomy, which was sufficient for complete repair in 82 patients. In midtrabecular ventricular septal defects, section of the moderator band (n = 24) allowed closure of all the defects with a single Dacron patch. In 48 patients a right atriotomy and a right (n = 32) or left (n = 14) (particularly for low trabecular ventricular septal defects) or both right and left (n = 2) ventriculotomies were necessary to secure the repair. The hospital mortality rate was 7.7% (10 patients). The causes of deaths were residual ventricular septal defect (n = 5), pulmonary hypertension (n = 2), hypoplastic right ventricle (n = 1) and left ventricle (n = 1), and myocardial infarction (n = 1). Among eighteen survivors with residual ventricular septal defect, six were reoperated on; there were two deaths. A permanent pacemaker was necessary in four patients. Low trabecular ventricular septal defects and left ventriculotomy were significant risk factors for morbidity (death, residual ventricular septal defect), p less than 0.01. At 7 years of follow-up, 90% of survivors were in New York Heart Association class I. Actuarial survival and freedom from reoperation at 7 years were 89.6% and 87.5%, respectively.

Tricuspid atresia. Results of treatment in 115 children.

We present our experience in the management of tricuspid atresia in 115 children. The anatomic data are categorized as follows: type I, 83.5%, type II, 16.5%. Type IB is the most frequent, representing 63.5% of all the cases. Each patient was operated upon one to four times. The age at first operation ranged from 10 days to 20 years. The first operation was a shunt in 94 children, a Fontan operation in four, and banding of the pulmonary artery in 17. Hospital mortality for the first operation was 12.2%, significantly higher in children under 6 months and in those having Waterston shunts. Potts and Blalock-Taussig operations give low long-term mortality; although few (six) have been done, Potts shunts also seem to give good long-term palliation in this series. The Glenn anastomosis is a good operation when performed after a systemic-pulmonary arterial shunt. The Fontan operation was performed in 24 children (hospital mortality 16.6%). There have been no late deaths after the third month postoperatively. Mean follow-up for this operation is only 2 years, but 88% of the survivors lead a normal life, two thirds of them receiving no treatment. There has been one reoperation for stenosis of a Dacron conduit with a good result. Late arrhythmias are well tolerated. In conclusion, the Fontan procedure is a good operation, but palliative procedures still allow good long-term survival.

Recurrent coarctation of the thoracic aorta: subclavian flap arterioplasty with carotid reimplantation of the distal subclavian artery.

Combining a subclavian flap procedure and reimplantation of the distal subclavian artery into the left carotid artery was used in 2 patients with recurrent coarctation of the thoracic aorta. One of the patients was 12 years old and the other, 6 years old. The operation has several advantages. (1) It is very efficient in relieving recurrent gradients. (2) The use of prosthetic material is avoided. (3) Minimal dissection is required. (4) It prevents subsequent subclavian steal syndrome and long-term ischemia of the left upper limb.

Absent pulmonary valve syndrome: surgical treatment and considerations.

BACKGROUND: The operative management of absent pulmonary valve syndrome remains controversial regarding the need for pulmonary valve implantation and remodeling of pulmonary arteries. Moreover, symptomatic infants are considered to have a poor prognosis. This retrospective report summarizes the experience of a single institution. METHODS: Between May 1977 and May 1995, 37 consecutive patients underwent repair of absent pulmonary valve syndrome. Patients were divided into two groups according to age at operation: group A (10 infants less than 1 year old) and group B (27 patients older than 1 year). Mean age at operation was 5 +/- 4 months in group A and 72 +/- 42 months in group B. Initially, repair consisted of ventricular septal defect closure and relief of right ventricular outflow tract obstruction combined with pulmonary valve implantation. More recently, the concept of treatment has evolved with pulmonary arterioplasty without pulmonary valve insertion, except in patients with elevated pulmonary artery pressure. RESULTS: Of the 37 patients, 34 had successful repair. The overall in-hospital mortality rate was 8% (two deaths in group A and one in group B). No hemodynamic data were correlated with operative death. Death was associated with longer extracorporeal circulation time (p = 0.005) and longer aortic cross-clamping time (p = 0.019). In fact, these were clearly related to more complex anatomy (p = 0.001): multiple ventricular septal defects in 1, left pulmonary artery arising from the ductus in another, and left pulmonary artery arising from the aorta in the remainder. Follow-up was available in 22 of the 34 survivors. Mean follow-up time was 30 +/- 47 months in group A and 38 +/- 33 months in group B. All but 1 had no restriction of exercise, and most of them had pulmonary incompetence of Doppler echocardiography. One developed severe exercise intolerance because of pulmonary valve stenosis (xenograft), leading to uneventful reoperation 123 months after initial repair. One infant died suddenly of complete atrioventricular block 3 months after repair. The late mortality rate was 5%. CONCLUSIONS: Surgical treatment of absent pulmonary valve syndrome should include pulmonary arterioplasty to reduce bronchial obstruction, with no need for pulmonary valve insertion. This procedure is feasible and is recommended especially in markedly symptomatic infants.

Post cardiac surgery phrenic nerve palsy in pediatric patients.

From January 1978 to December 1988, 109 phrenic nerve paralyses (PNP) occurred in a total of 9149 cardiac operations performed in a population of patients younger than 15 years old (1.2%) whose age varied from 1 day to 15 years old and mean weight was 11.3 +/- 8.7 kg. PNP was diagnosed in 43 patients after closed procedures (1.2% of 3509 procedures) and in 66 patients after open heart operations (1.2% of 5640 operations). PNP was right sided in 49 cases and left sided in 60 cases. Open heart operations that predisposed to PNP were those which needed harvesting of autologous pericardium (P less than 0.0001) and wide exposure of the great vessels. The modified right Blalock-Taussig shunt was the main cause of PNP in closed procedures (P less than 0.02). Small children tolerated PNP less well. They needed longer ventilatory support (P less than 0.0005) and developed more respiratory complications. Seventeen children underwent plication of the affected hemidiaphragm and could be subsequently extubated. It is concluded that for prevention of PNP, a high level of attention should be exercised in neonates and small children, particularly when pericardium is harvested or when exposure needs extensive dissection of the great vessels and thymus resection, or at reoperation. We also prefer to avoid the use of iced slush lavage. PNP, when symptomatic, is best managed by continuous positive airway pressure (CPAP) ventilation. Diaphragmatic plication is recommended when after 2-3 weeks there is no recovery of diaphragmatic function or when there are troublesome respiratory complications.

[Postoperative pulmonary emboli and their treatment]. / A propos des embolies pulmonaires post-opératoires et de leur traitement

Report on the present-day world experience on severe post-operative embolie. A univocal attitude was suggested in what concerns their diagnosis and their treatment, both medical and surgical.

[Complete correction of Fallot's tetralogy with a Waterston shunt]. / Cure complète de la tètralogie de Fallot avec anastomose de Waterston.

The influence of a Waterston shunt on the mortality in complete correction of Fallot's tetralogy varies from series to series. Some authors believe that it has no influence and others, on the contrary, believe it plays an important role to the point of recognising a particular premonitory syndrome of pulmonary hypertension and a low output state. This divergence of opinion in patients with comparable lesions is surprising, and cannot always be explained by poor surgical indications (irreversible pulmonary hypertension) or by problems of surgical technique. In our experience the conditions of cardiopulmonary bypass are of prime importance and we believe that the common factor in surgical failure is poor myocardial protection. This point of view is suggested by our present results in the correction of moderate and severe forms of Fallot's tetralogy under cardioplegia and seems to be reinforced by the results of extensive repair in forms with a Waterston shunt, said to be high risk procedures, that is to say with considerable asymmetry of the pulmonary vascularisation by stenosis of the right main pulmonary artery.

[Pulmonary stenosis with intact ventricular septum. Surgical experience in 200 cases, excluding the neonatal period]. / Sténoses pulmonaires à septum ventriculaire intact. Expérience chirurgicale de 200 cas à l'exclusion de la période néo-natale.

Experience over 10 years, studying two groups of patients (group I: 79 cases aged between 2 months and 2 years, group II: 151 cases aged over 2 years) has shown that the operative prognosis of severe forms is now the same as in simple forms. Interest is now focused on the long term function of the right ventricle with regard to the surgical procedure. The main discussion in management is between isolated pulmonary commissurotomy, whatever the anatomical form, and operations such as we perform which associate ventricular resection with or without an infundibular patch in severe cases. The possible causes of late ventricular dysfunction are discussed, especially the muscular resection, the operative myocardial protection and the preoperative myocardial sclerosis. The good results observed in this series as opposed to the doubt as to the cause and variability of late ventricular dysfunction do not justify a change in our management at present.

[Left superior vena cava simulating abnormal pulmonary venous return]. / Veine cave supérieure gauche simulant un retour veineux pulmonaire anormal.

The case of a seven year old boy with coarctation of the aorta and a left superior vena cava (SVC) draining into the left atrium is reported. Usually, in this condition the circulation is centripedal, descending from the left SVC to the left atrium and leading to systemic cyanosis or desaturation. In this case, the circulation was centrifugal and ascending from the left atrium to the left SVC to the innominate vein, leading to a left-to-right shunt as in abnormal pulmonary venous return. The left-to-right shunt flow was 4.2 l/mn and the ratio of pulmonary to systemic flow was 1.8: there was no pulmonary hypertension. This type of circulation is very rare and only two other cases were found in the literature. It may be explained by the proximity of the left pulmonary veins to the left SVC and by a functional mitral obstacle due to the increased pulmonary return. Simultaneous correction of the coarctation and ligature of the left SVC was carried out by left thoracotomy without cardiopulmonary bypass.

[Surgical treatment 0f 52 obstructive cardiomyopathies. 11-year experience (1964-75)]. / Traitement chirurgical de 52 cardiomyopathies obstructives. Expérience de 11 ans (1964 à 1975)

The authors present their 11 year experience of treating severe cases of obstructive cardiomyopathy which were resistant to medical treatment. They consider that myotomy is the simplest procedure (it is always effective) in this mysterious disorder for which it must be admitted that there is no treatment that is entirely satisfactory.

[Treatment of obstructive cardiomyopathy using myotomy in a 67-year-old patient. Pharmacological and angiographical studies]. / Traitement d'une cardiomyopathie obstructive par myotomie chez un sujet de 67 ans. Etudes pharmacologique et angiographique

The case is reported of a 67 year old man with obstructive cardiomyopathy treated by an extended myotomy. Serial phonomechanographic tracings and the pre- and post-operative angiograms show the steady progress of the disease towards a major disturbance of left ventricular compliance which became resistant to propranolol, and was partially reversed by myotomy.

[Atrio-ventricular canal. Apropos of 47 operated cases]. / Le canal atrio-ventriculaire. A propos de 47 cas opérés

The authors present their experience of this "bad reputation surgery". The operations performed ranged from pulmonary artery banding to complete reparation of A and B forms. They insist on the value of the assessment during operation of the quality of valvular repair.