Impact of transesophageal electrophysiologic study to elucidate the mechanism of arrhythmia on children with supraventricular tachycardia and no preexcitation

An electrophysiologic study (EPS) of children and teenagers with paroxysmal supraventricular tachycardia (SVT) and normal electrocardiography (ECG) in sinus rhythm was evaluated. Generally, EPS is performed only before paroxysmal SVT ablation in these patients. In this study, 140 patients (mean age, 15 ± 3 years) with normal ECG in sinus rhythm were studied for SVT by a transesophageal route in baseline state and after isoproterenol. Idiopathic left or right ventricular tachycardia was diagnosed in four patients (3 %). Anterograde conduction over an atrioventricular (AV) left lateral (n = 10) or septal (n = 9) accessory pathway (AP) was noted in 19 patients (13.5 %) at atrial pacing. Orthodromic AV reentrant tachycardia (AVRT) was induced in these children. Five of the patients had a high rate conducted over AP (>240 bpm in baseline state or >290 bpm after isoproterenol). Two of the patients (a 10-year-old girl with well-tolerated SVT and a 17-year-old with syncope-related SVT) had the criteria for a malignant form with the induction of atrial fibrillation conducted over AP at a rate exceeding 290 bpm in baseline state. Of the 140 patients, 74 (53 %) had typical AV node reentrant tachycardia (AVNRT), nine had atypical AVNRT (6 %), 1 had atrial tachycardia (0.7 %), and 33 (23.5 %) had AVRT related to a concealed AP with only retrograde conduction. Electrophysiologic study is recommended for children with paroxysmal SVT and normal ECG in sinus rhythm. The data are helpful for guiding the treatment. Ventricular tachycardia or atrial tachycardia can be misdiagnosed. Masked preexcitation syndrome with anterograde conduction through AP was present in 13.5 % of the patients, and 1.4 % had a malignant preexcitation syndrome.

Interest of non-invasive and semi-invasive testings in asymptomatic children with pre-excitation syndrome

AIMS

To determine the feasibility and the results of exercise testing (ET) and electrophysiological study (EPS) in outpatient asymptomatic children with a Wolff-Parkinson-White (WPW) syndrome.

METHODS AND RESULTS

Exercise testing and transesophageal EPS were performed in 55 outpatient asymptomatic children aged 6 to 19 years old (14 +/- 3) with WPW. Wolff-Parkinson-White persisted during maximal exercise. Isoproterenol was not required in five children younger than 10 years old, because they developed a catecholaminergic sinus tachycardia. Maximal rate conducted through accessory pathway (AP) was higher in children younger than 16 years old than in teenagers (P < 0.05). Atrioventricular re-entrant tachycardia (AVRT) was induced in six children; atrial fibrillation (AF) in 12 children. The induction of tachycardias and the dangerous forms (18%) were not influenced by age. After 5 +/- 1 years, one child, 12 year old with inducible rapid AF, had a sudden cardiac arrest; two children became symptomatic after ablation.

CONCLUSIONS

Transesophageal EPS was required to determine the prognosis of asymptomatic WPW in children. The maximal rate conducted in AP was higher in children younger than 16 years old than in teenagers; other data did not differ. AVRT was rare; 71% of children had no inducible arrhythmia and were authorized to resume physical activities.

[Implantable cardioverter defibrillators in pediatric patients: results in a series of 33 cases]

Implantable defibrillator is the recognized treatment of sudden cardiac death. Miniaturization of the devices allows implantation in children.

METHODS

This multicentric retrospective study analyzed data of 33 children aged 18 years and less who were implanted from 1990 to 2005.

RESULTS

Age of patients are 10 to 18 years, 20 patients were implanted after a resuscitation of sudden death, 10 after a syncope, 2 after a ventricular tachycardia and 1 in a prophylactic way. Tachycardias on primary electrical disease are most frequent (46%). Hypertrophic cardiomyopathy accounts for 22%, DAVD for 14%, congenital cardiopathies for 12%. Seventeen patients received appropriate shocks and 14 patients had inappropriate shocks. There were two unexplained deaths. Five leads fractures and two device infections were noted.

CONCLUSION

Implantable defibrillator is an effective treatment for children high-risk of sudden death. Occurrence of inappropriate shocks due to sinusal tachycardia, infections and leads fractures are frequent.

[Paediatric cardiac surgery and autoevaluation: risk score, complexity score and graphic analysis]

The creation of a paediatric surgical unit requires autoevaluation in order to: assess the quality of the results with respect to recognised international standards, answer the family's questions about the results obtained and adhere to criteria of accreditation Between January 2003 and December 2004, 201 consecutive patients, children (N= 164) or operated for adult congenital heart disease (N= 37) were treated. No patient was excluded. The RACHS-1 risk score, the ARISTOTLE scores of complexity and performance and the CUSUM and VLAD graphic analyses were applied to the study of hospital mortality. An original "variable performance-adjusted display" (VPAD) graphic analysis was performed to show up any possible variations of performance. Paediatric hospital survival was 97.56% (95% CI: 93.9 - 99.1). The paediatric complexity and performance scores were 6.79 +/- 0.22 and 6.62 respectively. In the absence of statistical significance in this field of autoevaluation, graphic analyses indicated the performance of our unit with no "learning" curves. Graphic scores and analyses allow assessment of the function of a paediatric cardiac surgical unit and the variations of complexity with respect to time, before the appearance of statistical significance. The ARISTOTLE complexity and performance scores and their adaptation in VPAD seem to be more reliable and discriminating than the RACHS-1 score.

[Complications of prostaglandin E1 treatment of congenital heart disease in paediatric medical intensive care]

The authors undertook a retrospective study of the modes of prescription, the tolerance and efficacy of prostaglandin E1 in 62 consecutive neonates with congenital heart disease (average Age 1.6 days: 35 boys: weight: 3.1 +/- 0.6 Kg) admitted to the paediatric intensive care unit of Nancy University Hospital between 1998 and 2002. The infusion time and cumulative dosage were 134 +/- 112 (6-480) hours and 111 +/- 94 (4-396) microg/Kg respectively. The side effects that were observed were: Apnoea (19%), abdominal distension (16%), bradycardia (13%), enterocolitis (6.5%), hypotension (6.5%), vomiting (5%), fever (1.6%) and skin rash (1.6%). Gastrointestinal disturbances are associated with a low body weight (p<0.04), to prolonged treatment (p<0.02) with no influence of initial or cumulative dosages (P=NS), with respiratory assistance (p<0.03) and longer hospital stay (p<0.01). Hypotension was commoner in cases of poor neonatal adaptation. Mortality was correlated with severe initial acidosis (p<0.02), a low Apgar score, the initial prolonged use of high doses of prostaglandin (p<0.04), and the presence of severe valvular aortic stenosis or hypoplasia of the left heart (p<0.002). The authors conclude that treatment with prostaglandin is effective in the majority of cases despite the use of low maintenance doses (0.01 microg/Kg/min). Gastrointestinal disturbances favourised by the perinatal context, the cardiac disease, and prolonged treatment are significant factors for morbidity and mortality. The beneficial role of early neonatal enteral feeding was not demonstrated in this high risk population.

Permanent junctional reciprocating tachycardia in children: a multicentre study on clinical profile and outcome

OBJECTIVES

To investigate the clinical profile, natural history, and optimal management of persistent or permanent junctional reciprocating tachycardia (PJRT) in children.

METHODS AND RESULTS

85 patients meeting the ECG criteria for PJRT were enrolled in a retrospective multicentre study. Age at diagnosis varied from birth to 20 years (median 3 months). Follow up ranged from 0.1 to 26.0 (median 8.2) years. At the time of referral, 24 of 85 patients (28%) had congestive heart failure that was resolved with medical treatment in all patients. Eighty three patients received drug treatment initially. Amiodarone and verapamil were the most effective with a success rate of 84-94% alone or in association with digoxin. Radiofrequency ablation of the accessory pathway was performed in 18 patients. There was a trend for a relation between age at ablation and the result of the procedure, failures being more common in younger patients (three of six procedures in younger and 15 of 18 in older children were successful; p = 0.14). Two patients with persistent left ventricular dysfunction on echocardiography but with no symptoms of congestive heart failure died suddenly one month and three years after diagnosis. PJRT resolved spontaneously in 19 patients (22%). Age at diagnosis of PJRT was not a predictor of spontaneous resolution.

CONCLUSIONS

PJRT is a potentially lethal arrhythmia in children with tachycardia induced cardiomyopathy. Spontaneous resolution of tachycardia is not uncommon. Antiarrhythmic treatment is often effective. Radiofrequency ablation should be performed in older children or when rate is not controlled, especially in patients with persistent left ventricular dysfunction.

Syndrome de délétion 22q11 et maladie de Basedow. À propos de trois observations pédiatriques

Hypothyroidism is a well recognized complication of 22q11.2 deletion syndrome. Auto-immune hyperthyroidism is less common. We report three patients with a 22q11.2 deletion and Graves' disease diagnosed at age 17, 14 and 11 years, respectively. The clinical and biological presentation was typical for auto-immune hyperthyroidism. Graves' disease should be periodically sought during the follow-up program of patients with 22q11.2 deletion syndrome.

[Kawasaki disease in newborns and infants: refractory forms to immunoglobulin therapy]

We studied 52 consecutive patients with Kawasaki disease hospitalized (1984 -2003) during the acute phase (mean age 2.5 + 2.4 years; range 0.3 to 16 years, 34 males, 18 cases with coronary aneurysms, median follow-up 6.7 years), and identified a subgroup presenting a refractory subtype to immunoglobulin therapy.

RESULTS

forty-nine infants benefited from a first regimen of immunoglobulins, 8.4 + 6 days following the onset of symptoms. Eleven infants (1.4 + 1.2 years, range 0.3 - 4.3 years, median 1.7 years) were non-responders, with coronary aneurysms in 8 cases (giant aneurysms (>8 mm) in 4 cases). These 11 infants were treated a second time by immunoglobulins, but 6 cases (1.8 + 1.6 years, with two cases of severe ventricular dysfunction and 2 cases of fatal myocardial infarction) required an additive therapy with (oral or IV route) corticosteroids (2) and cyclophosphamide bolus (4) with or without repetitive plasmapheresis (4). Non-responder patients had their treatment onset later (p<0.0003) using higher dosages (p<0.005), a longer delay for fever or biological signs correction (p<0.02), a worsening of coronary lesions (p<0.05) with more coronary secondary aneurysms (p<.005). The aneurysms, more frequent at the second phase of the disease (p<0.0001) are associated with: a younger age (p<0.03), a lower weight (p<0.02), a later onset of treatment (p<0.03), prolonged fever or inflammatory syndrome (p<0.05), higher level of fibrinogene (p<0.02). The overall mortality (5.7%) is correlated with giant aneurysms (p<0.001), myocardial ischemia (p<0.0001), heart failure (p<0.0001), and lack of early response to treatment (p<0.003).

CONCLUSION

immunoglobin therapy can be repeated. In case of severe forms, the use of corticosteroids, cyclophosphamide and plasmapheresis may be proposed.

[Late presentation of type A aortic arch blockage with a large type I aortopulmonary window]

We report the case of a 39 day old infant, hospitalised for congenital cardiopathy associated with type A blockage of the aortic arch with a large type I aortopulmonary window. The infant was in cardiogenic shock with pulmonary systemic hypertension and a tightly stenosed arterial canal (< 2 mm). With no possibility of re-opening the arterial canal under PGE1 at this stage, complete repair was performed as an emergency. After section of the aortopulmonary window, it was closed on the pulmonary side with a patch of autologous pericardium. Repair of the aortic arch was performed without prosthetic material, under selective cerebral perfusion to protect the brain parenchyma, after mobilisation of the descending thoracic aorta, which was anastomosed directly with the distal part of the window and aortic arch. Recovery was uncomplicated, with no residual lesion at 6 month post-operative follow up. The late clinical presentation of this patient shows the effect of medical management without prior catheterisation, with operative techniques minimising peri-operative tissular ischaemia and conserving aortic and pulmonary growth potential.

[General anaesthesia for Caesarean section in a patient with pulmonary atresia and an intact intraventricular septum]

We report the case of a 22-year-old primigravida patient presenting pulmonary atresia with intact ventricular septum, a rare congenital heart disease. Caesarean delivery was performed at 32 weeks of gestation because of moderate maternal function deterioration and foetal growth restriction. General anaesthesia was used because of the presence of lumbar Harrington rods. The administration of etomidate, celocurine and a continuous perfusion of remifentanil right from induction ensured haemodynamic stability and a rapid emergence and recovery.

[Cardiac stimulation in the infant and young child]

This study evaluates the problems and the evolution of cardiac stimulation in infants (aged < 3.5 years) by comparing the endocavity and epicardial routes in a retrospective series of 37 patients. Thirty seven patients aged 1.2 +/- 0.9 years treated with epicardial (n = 19) or endocavity (n = 18) stimulation were followed for 10.9 +/- 6.4 years (0.75-24). The 2 patient groups did not differ in age or weight. Four patients were lost to follow up, and 1 died. The functional duration of the first stimulator was not significantly different if the initial approach was epicardial or endocavity. The endocavity probes were introduced by venous denudation in 15 cases and by subclavian puncture in 3 cases. Fourteen of the 19 children fitted by the epicardial route went on to endocavity stimulation, of which 10 were at the first replacement. None of the 18 patients fitted by the endocavity route went on to epicardial stimulation. Out of 11 endocavity probe replacements and 9 atrialisations, the homolateral venous approach was always possible except in 2 cases. In conclusion, the results for the epicardial and endocavity routes are comparable. For technical reasons (calibre of the veins, size of the stimulator) it would appear reasonable if the endocavity route was used, making do initially with a mono chamber stimulation. The advances in the epicardial electrodes abolishes the major handicap (threshold elevation) of this approach which can be advocated when double chamber stimulation seems preferable.

[Isolated congenital complete atrio-ventricular block]

The objective of this work was to study the long term evolution of a retrospective series of 54 patients affected with congenital isolated complete atrio-ventricular block (CAVB) and to analyse the value of the different methods used for surveillance. Our series included 54 patients affected with isolated CAVB, without associated cardiopathy, diagnosed at an average age of 5.3 +/- 5.5 years, of which 9 were in utero. The average duration of follow up was 14.5 +/- 9.6 years. During the evolution, a cardiac stimulator was placed in 41 patients (76%) at a relatively late average age of 13.3 +/- 9 years, significantly lower for CAVB diagnosed before the age of 1 year (9.6 +/- 7.4 years) than for those diagnosed after the age of 1 year (16.2 +/- 9.2 years) (p < 0.02). The approach was endocavitary in 39 cases and epicardial in 2 cases. The only 2 deaths in our series (4%) concerned 2 patients of 18 and 26 years already fitted with a stimulator. Three patients progressed to severe dilated cardiomyopathy despite implantation of a stimulator. The decisive arguments for implantation of a PM were clinical (11 patients), Holter ECG (25 patients), stress test (17 patients), electrophysiological investigation (5 patients), echocardiography (3 patients) and surgical intervention (2 patients). In conclusion, our study confirms the good prognosis of isolated congenital complete atrio-ventricular block, but underlines the possible progression in rare cases in spite of stimulation towards dilated cardiomyopathy for which the aetiology remains uncertain. Three quarters of the patients required a stimulator at a somewhat late age.

[Sports and congenital heart disease in the adult]

The practice of sporting activities is not only allowed, but also should be recommended for most adult patients affected by congenital cardiopathy. This permissive attitude should be based on a good understanding of congenital cardiopathy, whether operated or not, and its foreseeable evolution in adulthood. Aptitude for sport should be supported by a precise evaluation of the patient's functional, rhythmological and haemodynamic status at rest and under effort. Regular monitoring is often justified, and is greatly facilitated by the quantity and quality of modern non-invasive surveillance methods, the first of which are Doppler echocardiography and ergometric techniques. The stress test should be readily coupled with a study of ventilatory parameters under effort, as there are frequently disturbances of pulmonary exchange. Non-competitive sporting activity is generally implied for congenital cardiac patients, but there are exceptions in certain cases. Patients should generally be directed towards an endurance sport, undertaken without any spirit of competition, as a function of the results from effort tests (easy confrontation for this type of sport). It is only based on the tolerance of this basal activity that other sports are then authorized. It is illusory to demand systematisation for sporting aptitude in each type of cardiopathy as the situations encountered in practice vary from one individual to another. It is nevertheless possible to define a certain number of guidelines which are suitable for modification for each patient as a function of the clinical history, any associated vascular risk factors, and the patient's motivation. All said and done, absolute contra-indications to sport are rare. Relative contraindications to a type of sport or to a level of sporting activity as a function of the cardiopathy are encountered more and more. Nowadays the selective aptitude for certain sports should be discussed rather than the contra-indications. Under these conditions, sport can only be beneficial for adult congenital cardiac patients, and it plays a part in the prevention of the acquired risk of cardiopathy from which these patients have no escape.

[Twin-twin transfusion syndrome: report of two cases with hemodynamic complications]

CASE REPORTS

We report two cases of cardiac dysfunction in twin-twin transfusion syndrome (TTTS) evaluated with serial echocardiography. Two cases of TTTS were referred at 27 and 26 weeks. At delivery at 31 weeks, the first recipient twin had evidence of severe cardiac dysfunction with decreased ventricular function and transient systemic hypertension. There was polycythaemia. Favorable outcome was observed after treatment with arterial vasodilating (nicardipine) and inotropic agents (dobutamine, enoximone), and reduction of haematocrit. At 28 weeks the other recipient twin had cardiac dilatation with hypokinetic myocardium. These alterations were cured by dobutamine.

CONCLUSION

These cases show that even severe cardiac dysfunction may be reversed after birth unlike in utero natural evolution.

[Role of pediatric cardiologists in the management of neonates with congenital heart disease]

Whether diagnosed before birth or suspected in a newborn, congenital heart diseases rapidly require an evaluation by the pediatric cardiologist. The role of the pediatric cardiologist is threefold: 1) to realize a careful anatomical examination using color Doppler echocardiography; 2) in many cases to perform a palliative or curative therapeutic act based upon interventional catheterization, such as Rashkind atrioseptotomy or percutaneous balloon valvuloplasty; and 3) whenever necessary, to take a rapid decision of cardiac surgery in concert with the cardiac surgeon, and to prepare the child for surgery.

Paroxysmal tachycardia in children and teenagers with normal sinus rhythm and without heart disease

The purpose of this study was to evaluate the value of esophageal programmed stimulation in children and teenagers with normal sinus rhythm ECG and normal noninvasive studies, having palpitations and syncope, and no documented tachycardias. Paroxysmal tachycardias are frequent in children and are often related to accessory connection. These tachycardias are sometimes difficult to prove. Transesophageal atrial pacing was performed at rest and during infusion of isoproterenol in 31 children or adolescents aged 9-19 years (16 +/- 3 years) with normal sinus rhythm ECG and suspected or documented episodes of paroxysmal tachycardia. Sustained tachycardia was induced in 27 patients, at rest in 13 patients, and after isoproterenol in 14 remaining patients. Atrioventricular nodal reentrant tachycardia was found as the main cause of paroxysmal tachycardia (22 cases). Six patients were followed by a vagal reaction and dizziness. These patients had spontaneous tachycardia with syncope. In three other patients, atrial fibrillation was also induced. Concealed accessory pathway reentrant tachycardia was identified in three patients. In two patients, a regular wide tachycardia with right bundle branch block morphology was induced; the diagnosis of verapamil-sensitive ventricular tachycardia was made in a second study by intracardiac study. In conclusion, atrioventricular nodal reentrant tachycardia was found as the main cause of symptoms in children with normal sinus rhythm ECG. Syncope is frequently associated and provoked by a vagal reaction. This diagnosis could be underestimated in adolescents frequently considered as hysterical because noninvasive studies are negative.

[Junctional tachycardia in adolescents: nodal reentry is the most frequent cause]

Ventricular preexcitation syndromes are classically more common in the pediatric age group than in adults, and a latent Kent bundle may explain most cases of paroxysmal junctional tachycardia (PJT). These data stem from the results of intracardiac electrophysiologic testing, which is performed only in those patients at the most severe end of the symptom spectrum. The recent introduction of transesophageal testing has expanded the indications of electrophysiologic testing for PJT. This technique was used to determine the mechanism of PJT in 23 adolescents aged 11 to 9 years (mean age, 16 +/- 3 years) with paroxysmal palpitations, accompanied in seven cases with dizziness or syncope. Only four patients had documented PJT. The basal ECG was normal, and exercise testing showed no evidence of preexcitation. Pacing at increasing rates and programmed stimulation with one then two extra-stimuli was used and repeated, if needed, under infusion of 20 to 30 micrograms of isoproterenol.

RESULTS

PJT was induced in 21 patients (91%), under basal conditions in 13 and under isoproterenol in eight. Neither of the two patients with a negative test had documented tachycardia. Based on classic criteria (position of A relative to V1, effect of a bundle branch block, and shape of A in D1 and V1), the mechanism of the PJT was shown to be nodal reentry in 17 cases (81%) and reentry into a latent left-sided Kent's bundle in four cases. Atrial fibrillation was also induced in two of the patients with nodal reentry. In six of the patients with dizziness or syncope associated with palpitations, these symptoms were due to nodal reentry.

CONCLUSION

Nodal reentry is very common in adolescents and can explain symptoms ascribed to "spasmophilia", as well as some cases of malaise or syncope.

Induction of sustained ventricular tachycardia after surgical repair of tetralogy of Fallot

Between 1980 and 1996, 89 unselected consecutive patients with repaired tetralogy of Fallot (TOF) underwent examination, including a prospective right ventricular programmed stimulation with the same protocol (S1 S2, S3, S4). Age at surgery was 4.2 +/- 3.5 years and age at electrophysiologic study was 10.9 +/- 6.5 years. Follow-up since surgery was 14.4 +/- 4.8 years and patient follow-up after programmed stimulation was 7.8 +/- 4.2 years. The aim of this study was to evaluate the main predictors of the inducibility of a sustained monomorphic ventricular tachycardia (VT) and its significance to identify a group of patients at risk of sudden death: 21 (group A) had and 68 (group B) had no induced sustained VT. The induction of VT was related to older age at programmed stimulation, prolonged QRS duration, presence of complex ventricular arrhythmia, symptoms, right ventricular overload, and increased right ventricular systolic pressure. Predictors of induced VT selected by multivariate analysis were age at electrophysiologic study (p <0.0001), previous palliative shunts (p <0.001), right ventricular systolic pressure (p <0.007), and symptoms (p <0.005). Among group A patients, 4 had previous sustained VT before stimulation, and 1 had sustained VT only during follow-up after stimulation. No patients of group B had clinical sustained VT. Late mortality was low but similar between both groups. A negative electrophysiologic study may be helpful for the management of patients after surgical repair of TOF, but because the arrhythmic event rate is low, the findings of even a positive electrophysiologic study should be interpreted with caution.

Surgical management of progressive pulmonary venous obstruction after repair of total anomalous pulmonary venous connection

BACKGROUND

The occurrence of a progressive pulmonary venous obstruction after the repair of the total anomalous pulmonary venous connection is a severe complication.

OBJECTIVES

The objectives of this study were to retrospectively review the patients with this condition and to report our experience with a new surgical technique with a sutureless in situ pericardium repair.

METHODS

Of 178 patients who underwent correction of total anomalous pulmonary venous connection, 16 patients (9%) experienced the development of a progressive pulmonary venous obstruction in a median interval of 4 months (5 weeks-12 years). Three patients had isolated anastomotic stenosis, 4 patients had isolated pulmonary venous ostial stenosis, and 9 patients had both. Pulmonary venous obstruction was bilateral in 7 patients. The surgical procedures used at reoperation included 8 patch enlargements, 5 ostial endarterectomies, 1 intraoperative stenting, and 7 sutureless in situ pericardium repairs.

RESULTS

There were 4 deaths after reoperation (4 of 15 patients; 27%). The only significant mortality risk factor was the bilateral location of the pulmonary venous obstruction (P =.045). In patients with isolated anastomotic stenosis or with only 1 pulmonary venous ostial stenosis (n = 5), there was no death, except the patient presenting with a single ventricle. In patients with 2 or more pulmonary venous ostial stenoses (n = 10), there were 3 deaths; 5 of the 7 survivors were successfully treated with the in situ pericardial technique, with normalized pulmonary artery pressure at a mean follow-up of 26 months.

CONCLUSION

Progressive pulmonary venous stenosis after repair of total anomalous pulmonary venous connection remains a severe complication when bilateral. The sutureless in situ pericardial repair offers a satisfactory solution, particularly on the right side.

[5-year results of arterial correction in transposition of great vessels]

A prospective study was performed on in-hospital patients between June 1985 and July 1992 to assess the 5 year results of surgical detransposition of the great arteries. Clinical examination, electrocardiography, echocardiography, right and left heart catheterisation with selective coronary angiography, isotopic right and left ventricular ejection fractions at rest and with infusion of dobutamine and SestaMibi myocardial perfusion scintigraphy at rest and with dipyridamole, were performed during the 5th year after surgery. Twenty-six children underwent this protocol: eight others did not come for examination because they had moved from the region, one of whom had suffered regressive postoperative myocardial infarction. All patients were asymptomatic and had only minor electrocardiographic changes. Stenosis of the pulmonary tract was observed in 38.5% but only one case of stenosis at the origin of the right pulmonary artery required percutaneous angioplasty, which was successful. Pulmonary regurgitation was a common echocardiographic finding (65.4% of cases) but rarely severe (1/26: 3.9%). Aortic regurgitation was also observed commonly (53.8%), nearly always mild, grade I (13/14 cases). No significant stenosis of the aortic anastomosis was observed. The right and left ventricular ejection fractions were normal at rest except in one case and all values improved with dobutamine. Myocardial scintigraphy did not show any perfusion defect and there was no stenosis or occlusion of the coronary arteries at coronary angiography. The authors conclude that the results of arterial detransposition at 5 years are satisfactory in this series, with no cases of major obstructive lesions, major ventriculo-arterial regurgitation, ventricular dysfunction or coronary lesions. However, longer term trials with larger numbers of patients are required to determine the real incidence of coronary lesions and the long-term outcome of the pulmonary valve in the systemic position.

[Familial supravalvular aortic stenosis. Investigation in a family and review of the literature]

Familial supravalvular aortic stenosis is a rare autosomal dominant condition. It may be distinguished from the Williams-Beuren syndrome by the absence of the characteristic dysmorphic appearances and of mental retardation. The case of a 9-year-old girl with a severe surgical stenosis led to the diagnosis of the same malformation in the mother and two brothers. This family adds to the 121 cases reported in the literature describing the main features of SVAS. Molecular biological advances have shown that familial SVAS and the Williams syndrome are due to mutation of the elastin gene located at 7q11-23. In the Williams syndrome the allele of this gene is completely absent and there is also probably deletion of contiguous genes, which explains involvement of cognitive function. In SVAS, the genetic lesion, mutation or microdeletion is more limited, explaining the usually isolated aortic malformation. Other studies are necessary to confirm these results.

[Prognosis and outcome of idiopathic dilatation of the right atrium in children. A cooperative study of 15 cases]

Idiopathic dilatation is a rare abnormality corresponding to isolated aneurysmal dilatation of the right atrium, the outcome of which is not well known. Therefore a multicentric retrospective study was set up by the paediatric working group of the French Society of Cardiology recensing 7 boys and 8 girls who were diagnosed with this condition between 1971 and 1993. Ten of the children were asymptomatic and the diagnosis was suggested by the chest X-ray: one neonate had cardiac failure secondary to atrial tachycardia. The diagnosis has been facilitated by echocardiography since 1980. In this series, since 1993, four diagnoses were made antenatally. The outcome was variable : eight children are alive and well with follow-up periods ranging from 2 to 15 years (average 6 years) : four children have had cardiac arrhythmias : benign atrial extrasystoles (1 case), junctional reentrant tachycardia (1 case). The other two had more severe arrhythmias with flutter in a 7 year-old and one neonatal atrial tachycardia. The outcome was favourable with medical treatment. Three children underwent surgical atrial resection : the outcome has been good in these 3 cases with follow-up periods of 4, 13 and 18 years. This series shows that idiopathic dilatation of the right atrium is usually a well tolerated abnormality but unexpected complications may arise which can be severe such as arrhythmias, or which may be potentially threatening such as interatrial thrombosis. Management consists of either follow-up to diagnose complications which require appropriate treatment of systematic surgical correction as some authors suggest.

[French experience in the closure of atrial septal defects of the ostium secundum type with the Sideris button occluder]

From February 1992 to November 1995, four French teams used the Sideris button occluder to close 122 ostium secundum, foramen ovale or surgical fenestration atrial septal defects in 121 patients aged 2 to 79 years with body weights of 10 to 96 kg. a left-to-right shunt in 110 cases (average QP/QS = 2.09) or right-to-left shunt in 12 cases. The usual type of prosthesis was used in 115 cases, 8 centered on a guide wire, reverse type in 5 cases and the "centering-device" type in 2 patients. Nineteen implantation attempts were abandoned before releasing the prosthesis. The immediate results were: closure of the atrial septal defect in 116 patients: 59 were completely occluded, 43 had minimal residual shunts. Five patients were operated for non-buttoning or malposition of the prosthesis. In one other case, the device was removed by catheterisation. During follow-up ranging from 1 month to 3 years, 20 patients were operated for varying complications, the commonest of which was malposition of the prosthesis (17 cases) with a shunt of variable volume. In one other case, a second device was inserted. Seventy-seven patients were reviewed at 1 year, 28 a 2 years and 6 at 3 years. The residual shunts decreased with time but only completely disappeared in half the cases. Secondary fractures not requiring surgery were observed in 5 patients. Failures and complications were the result of various causes which are discussed. Successive technological improvements and the experience of the medical teams should reduce this incidence, but caution is required especially in the treatment of young children.

[Effects of age on the response to Tilt test in patients with malaise or syncopes]

The diagnosis of vasovagal malaise or syncope, suspected from the clinical history, may be confirmed by the tilt test. The aim of this study was to assess the effects of age on the results of this test in 346 patients who had unexplained malaise or syncope. Thirty-one patients were 7 to 19 years of age (group I), 59 were 20 to 40 (group II), 72 were 41 to 60 (group III) and 184 were 61 to 85 years old (group IV). The patients were maintained in the dorsal decubitus position for 20 minutes and then raised to 70 degrees until a malaise was observed or for a maximum of 40 minutes. The malaise or syncope was reproduced by the tilt test in 135 cases (39%). The number of positive responses was comparable in group I, II, III and IV (45, 42, 32 and 40%, respectively). The time before the malaise occurred was also similar in the four groups (17, 19, 15 and 20 minutes, respectively). Two responses to the tilt test characterised the different age groups: the greater number of malaises occurring independently of a drop in blood pressure or change in heart rate ("psychiatric" syncope) in group II compared with groups I, III and IV (40% versus 7, 9 and 9.5%); the higher frequency of pure vasodepressive forms in group IV compared with groups I, II and III (66% versus 28.5, 32 and 39%). In conclusion, the probability of a positive tilt test does not change with age. The mechanisms of the symptoms produced is the only difference observed with age.

[Long-term efficacy and tolerability of amiodarone in children]

The authors reviewed the files of 37 patients under 15 years of age (22 boys and 15 girls) in order to study the long-term efficacy and tolerance of amiodarone therapy. The mean age of the patients at the time of initiation of amiodarone was 6.2 +/- 4.7 years. Amiodarone was prescribed at a loading dose of 500 mg/m2 and at a maintenance dose of 250 mg/m2. This drug was prescribed in second intention in 29/37 patients and as monotherapy in 15/37 patients. The treated arrhythmias were supraventricular in 25 patients (atrial: 10; junctional: 15) and ventricular in 12 patients. Underlying cardiac disease was present in 21/37 patients (57%) and the arrhythmias were postoperative in 14/37 cases (38%). Efficacy and tolerance of amiodarone were estimated on clinical and biological data, the results of Holter monitoring, ophthalmological slit-lamp examination and thyroid function tests. The average duration of therapy was 4 +/- 3 years. The efficacy of amiodarone was judged to be good in 59% and satisfactory in 38% of cases. Secondary effects and complications included: corneal deposits: 14 cases (38%); skin pigmentation: 1 case; photosensitivity: 10 cases (27%). There was a high incidence of thyroid disorders: 7 cases (19%) with 4 cases of biological or clinical hyperthyroidism and 3 cases of clinical or biological hypothyroidism.(ABSTRACT TRUNCATED AT 250 WORDS)

[Repeated thrombolysis and difficulties in treatment with antivitamin K in an infant with mitral valve prosthesis]

The finding of cardiac failure in a neonate led to the diagnosis of congenital mitral regurgitation complicating dystrophic valves. After failed surgical valvuloplasty, the child underwent mitral valve replacement with a Saint-Jude medical prosthesis at the age of 4 months. The child developed four episodes of prosthetic valve thrombosis in the two years that followed. The first was treated surgically but the three others were treated by thrombolysis associating plasminogen tissue activator and urokinase. All but one of the thromboses occurred in a context of recent destabilisation of oral anticoagulant therapy despite the initiation of heparin. Repeat thrombolysis was successfully undertaken, thereby widening the indications of this type of treatment in the infant. This case also underlines the difficulties of oral anticoagulants in infants.

[Interventional catheterization in infants and neonates]

Indications for interventional catheterism in new-born and very young infants have been widened through technical progress and clinical experience. Such procedures are still very difficult to perform at this age and many indications are still under debate. Currently interventional catheterism is used for curative treatment of tight pulmonary valve stenosis, the pulmonary stenosis in Fallot's tetrology, clinically threatening aortic valve stenosis in infants or new-borns. Other procedures include vessel dilatations, in particular for coarctation of the aorta, placing vascular stents, closing ductus arteriosus or vascular embolizations. The question of the respective role of surgery versus interventional catheterism remains open for many indications. As progress is made, both techniques remain valid and should be considered as complementary tools for many congenital heart diseases.

[Total cavopulmonary shunts. Short- and mid-term results apropos of 19 cases]

Experimental and clinical studies show that total cavopulmonary shunt operations may prevent certain complications of the Fontan atriopulmonary procedure. The authors have used the total cavopulmonary shunt instead of the Fontan procedure since February 1990. Nineteen consecutive patients were operated by three different surgical teams; 18 patients had undergone prior palliative surgery. The shunt was carried out by Puga's modified Kreutzer technique or by the construction of an extracardiac autologous pediculated pericardial tube. There were two deaths (10.5%) attributed to severe stenosis of the left pulmonary artery. The postoperative course was complicated in most of the 17 survivors but after a follow-up of 3 to 57 months (average 24.9 +/- 13.6 months) all were in the NYHA functional classes I (N = 15) or II (N = 2) with an arterial saturation over 85% in 15/17 cases and a cardiothoracic index less than 53% in 14/17 cases. All were in sinus rhythm. Doppler echocardiography showed no obstruction of the bypass. Pulmonary flow in 11 cases had a venous morphology. The function of the single ventricle was slightly depressed in 3 cases (2 of which were operated late, at 16 years of age). Catheterisation and cavography in 13 children showed uniform pressures in the cavopulmonary connection with no pressure gradient, except in 1 child. A right atrial'a'wave transmitted to the pulmonary arteries and inferior vena cava accompanied by retrograde vena cava flow was observed in 4 of the 6 cases with a Puga or modified Kreutzer procedure. Fenestration of the connection was closed by a Sideris button device in one case; reoperation was required in another.(ABSTRACT TRUNCATED AT 250 WORDS)

No evidence for linkage to the type 1 or type 2 neurofibromatosis loci in Noonan syndrome families

A linkage analysis has been performed on 6 two-generation families with classical Noonan syndrome to determine whether the syndrome is linked to neurofibromatosis type 1 on chromosome 17q or to neurofibromatosis type 2 on chromosome 22q. A significantly negative location score was obtained between 10 cM centromeric to and 15 cM telomeric from the neurofibromatosis type 1 locus. A significantly negative lod score was obtained with a marker mapping within the region where neurofibromatosis type 2 is thought to be located. These data indicate that Noonan syndrome is not tightly linked to either neurofibromatosis type 1 or type 2.

[Percutaneous angioplasty of aortic recoarctation: short- and mid-term results in 18 cases]

Between January 1986 and July 1992, 18 percutaneous angioplasties were performed in 18 consecutive patients with recoarctation of the aorta, who were aged 2 months to 29 years. Fifteen had been operated for coarctation of the aorta and 3 for interruption of the aortic arch. The diameter of the dilating balloon was the same, to 1 mm, as that of the healthy aorta, usually measured just proximal to the stenosis. There were 3 femoral artery thromboses; one small aneurysm which did not increase in size, and 1 hypertensive crisis in a child. The diameter of the stenosis increased by 42.39 +/- 34.24%, the gradient decreased from 41.39 +/- 14.58 mmHg to 23.7 +/- 16.30 mmHg and the Doppler gradient from 57.89 +/- 15.29 mmHg to 36.55 +/- 16.50 mmHg. Eight angioplasties, including 5 of the last 7 procedures, were considered primary successes by 2 criteria: increase of the diameter of the stenosis by at least 40% and a residual catheter gradient of less than 20 mmHg. The best results were obtained in severe, localised central stenoses. Sixteen patients were followed up for 2 to 69 months. Two were operated after failed angioplasty, without complications. No late aneurysms or restenoses were observed in the cases successfully dilated followed up clinically (7), by MRI (5) or catheterisation (2). In one case, aortography showed remodelling with normalisation of the aortic arch after 24 months. These results indicate that percutaneous angioplasty is a simple method of treating recoarctation of the aorta, which is most effective in severe stenoses: the immediate risk is low. The late risks of recoarctation and aneurysm justify systematic follow-up.

[Mid-term results of balloon percutaneous valvuloplasty in the treatment of aortic valve stenosis in children and adolescents]

Fourteen consecutive patients aged 10.2 +/- 4.2 years with congenital valvular aortic stenosis underwent percutaneous balloon aortic valvuloplasty (PBAV) which reduced the peak-to-peak LV-aortic pressure gradient from 81.2 +/- 16.7 mmHg to 27.5 +/- 12.5 mmHg and the maximal instantaneous Doppler gradient (Dopp G) from 70.0 +/- 13.4 mmHg to 31.4 +/- 12.3 mmHg. These 14 patients were followed up 3.6 +/- 1.1 years after PBAV. Control Doppler examination showed the Dopp G (34.8 +/- 15.4 mmHg) to be comparable to that measured just after PBAV (31.4 +/- 12.3 mmHg). One patient, the only one with a mediocre, immediate result, had to be operated 5.5 years after PBAV. Aortic regurgitation was observed on aortography before PBAV in 10 patients: it remained unchanged in 7 and was aggravated in 3 patients. Aortic regurgitation was observed for the first time after PBAV in 3 patients. At control Doppler examination, aortic regurgitation was present on color Doppler in all cases but was mild or minimal in 9 cases. In one patient, secondary aggravation of aortic regurgitation required aortic valve replacement (homograft) 3 years after PBAV. Four of the 16 PBAV (25%) were performed in these 14 patients were complicated by a femoral arterial thrombosis. This study shows that the good primary results of PBAV in the treatment of congenital valvular aortic stenosis in childhood and adolescence, are maintained at medium-term. The risk of creating severe aortic regurgitation is not completely negligible but does not seem to be out of proportion compared with surgical valvotomy.

[Percutaneous angioplasty of branch pulmonary artery stenosis. A cooperative study]

Fifty balloon angioplasties of branch pulmonary artery stenosis in 34 patients aged 4 months to 20 years, performed in 7 French Centres, were included in this study: they were performed from 1984 to 1991 and concerned severe stenoses which were congenital in 36 cases and secondary to surgery in 14 cases. The criteria of inclusion were: diameter of stenosis less than or equal to 8 mm, right ventricular systolic pressure (RVP) greater than or equal to 50 mmHg, RVP/aortic pressure ratio (RVP/AO) greater than or equal to 50%, and a significant perfusion defect on radionuclide angioscintigraphy. There were no operative complications. The diameter of the stenosis increased by greater than 40% in 23 cases (46%); in only 7 of these cases (14%) did the RVP and RVP/AO ratio decrease by more than 20%, the RVP being less than 50 mmHg, or did the perfusion scintigraphy improve. No cases of restenosis were observed. The reasons for failure are discussed together with the limitations of this study. The respective indications of surgery and angioplasty are not easy to determine for these complicated lesions. New techniques such as the use of stents should improve results.

Right ventricular overload and induced sustained ventricular tachycardia in operatively "repaired" tetralogy of Fallot

The aim of the study was to evaluate the main predictors of the inducibility of sustained ventricular tachycardia (VT) in patients with repaired tetralogy of Fallot. Thirty-five patients (age 12 +/- 6 years) underwent right-sided cardiac catheterization, echocardiography, radionuclide angiography and ventricular stimulation; 10 had (group 1) and 25 had no (group 2) sustained VT. Group 1 patients were significantly older at the time of surgery and had longer follow-up periods (7 +/- 3 vs 4 +/- 4 years, p less than 0.02; and 12 +/- 4 vs 5 +/- 2 years, p less than 0.001, respectively). Right ventricular (RV) systolic pressure, end-systolic and end-diastolic normalized RV volumes were higher in group 1 (48 +/- 14 vs 38 +/- 11 mm Hg, p less than 0.05; 1.23 +/- 0.2 vs 0.86 +/- 0.17, p less than 0.001; and 2.35 +/- 0.37 vs 1.70 +/- 0.22, p less than 0.001, respectively). RV end-diastolic pressure, left ventricular and RV ejection fractions were similar in the 2 groups. A stepwise discriminant analysis was made to predict patients with inducible sustained VT (group 1): Time period from surgery to follow-up (p less than 0.001), normalized RV end-systolic volume (p less than 0.002) and RV systolic pressure (p = 0.01) were higher in group 1 and allowed classification of 90% of patients in group 1 and 96% in group 2.(ABSTRACT TRUNCATED AT 250 WORDS)

[Non-surgical repair of atrial septal defect by "buttoned" double disk device in children. First results in 3 children]

Transcatheter closure of ostium secundum atrial septal defect (ASD) with a "buttoned" double-disk device was attempted in 5 children aged 14 months to 12 years, with success in 3 cases. The diameter of the ASD was 15 to 20 mm. The occluding devices were chosen with sizes 12-15 mm greater than those of the ASDs. There were no operative complications: the ASD was practically completely occluded in 2 children and left a very small shunt in a third case. Those three patients are doing well, 8 to 9 months after the procedure. In the other two cases, the device fell into the right atrium and had to be removed surgically without any complications. The "buttoned" double-disk device seems to be relatively simple and easy to insert through an 8F catheter. Additional technical improvements should enable more complete occlusion of ASD and easier retrieval by the transvenous route when incorrectly inserted. Further experimental and clinical studies are required to assess the results and to compare them with those of the other teams.

[Effect of complete bundle-branch block on the averaged signal of high amplification electrocardiogram]

Intraventricular conduction defects delay ventricular activation and change the appearances of the signal averaged electrocardiogram. The aim of this study was to determine criteria capable of identifying patients with bundle branch block at high risk of ventricular tachycardia (VT). Two hundred and twenty four patients were studied by Simson's method. One hundred and twenty eight patients (Group I control) had narrow QRS complexes and sequellae of previous myocardial infarction. Eighty four patients had no clinical or inducible VT; 44 had clinical and/or inducible VT with programmed stimulation. Forty six patients (Group II) had complete right bundle branch block (RBBB); 30 had no VT and 16 had VT. Twenty seven patients (Group III) had complete left bundle branch block of whom 18 had no VT and 9 had VT. Twenty three patients (Group IV) had RBBB with operated tetralogy of Fallot; 16 had no VT and 7 had VT. In the control group, the results of signal averaged ECG were the same as those reported in the literature: prolongation of the duration of the averaged QRS (136 +/- 35 ms vs 104 +/- 14 ms), decrease in amplitude of the last 40 ms (11 +/- 15 microV vs 43 +/- 28 microV) and an increase in the duration of less than 40 microV terminal activity (53 +/- 30 ms vs 28 +/- 11 ms) in those subjects with VT compared to those without VT. In Groups II, III and IV no significant difference was found in the amplitude of the last 40 ms or duration of less than 40 microV activity between patients with and without VT.(ABSTRACT TRUNCATED AT 250 WORDS)

[Cardiac rhabdomyoma in children and Bourneville's tuberous sclerosis]

Cardiac rhabdomyomas are rare congenital tumours resulting from an early dysembryoplastic disorder of organogenesis. They are generally benign hamartomas which may be the first manifestation of a phakomatosis, tuberous sclerosis (TS) (Bourneville disease), present in over half of cases. The cases of 11 children with cardiac rhabdomyomas are reported. All of them also had extracardiac lesions of TS. Their ages ranged from 1 day to 6 years of age. In one case, the diagnosis was made antenatally by foetal echocardiography. The clinical expression may be very serious when there are hemodynamic disturbances resulting from an obstructive syndrome (N = 3) or arrhythmias (N = 2). Nevertheless, the cardiac evolution is usually favorable (N = 9) in contrast to the neuropsychiatric outcome which is generally catastrophic (N = 8). The diagnosis is made by two-dimensional echocardiography and magnetic resonance imaging. Surgical resection of the tumours is reserved for forms complicated by cardiac failure due to intracardiac obstruction (N = 2) of life-threatening resistant arrhythmias. Genetic counseling should be directed towards prevention of TS because it is transmitted in an autosomal dominant mode. However, most of the cases are sporadic. Echocardiography should be systematic in all children with TS and is also recommended for members of their families, even those apparently unaffected, in order not to miss paucisymptomatic forms of TS.

[Percutaneous angioplasty of recoarctations of the aorta. Apropos of 11 cases]

Between January 1986 and October 1988, 11 young patients aged from 3 months to 29 years (10.6 years) underwent percutaneous transluminal angioplasty for recoarctation of the aorta. The procedure was performed 3 months to 21 years (6.7 years) after the initial operation for coarctation (9 cases: 8 terminoterminal sutures and 1 Waldhausen operation) or for complete interruption of the aortic arch (2 cases: direct terminoterminal suture with banding of the pulmonary artery in 1 case and closure of an aorto-pulmonary fistula in the other case). The diameter of the balloon selected was at most 1 to 1.5 mm wider than that of the smallest diameter of the aorta upstream or downstream of the stenosis, as measured by prior aortography. Adverse events recorded were thrombosis of the femoral artery in a 1-year old child, transient subendocardial lesion wave during dilatation in another child, and regressive left bundle branch block in a third patient. In one patient a small aneurysm developed at the site of dilatation: it was perfectly stable after 8 months. A satisfactory result was obtained in 4 cases, with a 52 to 95% increase in diameter of the stenosis and reduction of the gradient which fell from 56 mmHg on average to 18.25 mmHg. One child was lost sight of; in the remaining 3 patients the result remained stable after 6 to 20 months. A partial result (widening of the stenosis without change in gradient) was obtained in 2 cases. Five of the 11 cases were failures.(ABSTRACT TRUNCATED AT 250 WORDS)