[A cause of dilated cardiomyopathy in a child: primary carnitine deficiency]. / Une cause de cardiomyopathie dilatée chez l'enfant: le déficit primaire en carnitine.

AIM: The aim of this case report was to show the importance to research metabolic etiology, especially a carnitine deficiency in dilated cardiomyopathy of children. CASE REPORT: A three years old Togolese child presented muscular hypotonia, dyspnea. Examination showed left galop murmur and systolic murmur 2/6. Chest X-ray showed cardiomegaly (CTI: 0.66), electrocardiogram, a sinusal rythm, left ventricle hypertrophy and T wave abnormalities. Echocardiogram showed a markedly dilated left ventricle with reduced systolic function (EF: 0.43; reference range 0.55-0.80) and moderate mitral regurgitation. The inflammatory signs where negatives. Magnetic resonance imaging don't show signs of ischemic or myocarditis. The levels of free and total plasmatic carnitine decreased: 3µmol/L (N: 18-48µmol/L) and 5µmol/l (N: 29-70µmol/L) respectively. Mutation analysis of the gene SLC22A5 confirms the diagnosis of primary systemic carnitine deficiency. Treatment with oral carnitine was started at 200mg/kg per day. Within three weeks of treatment, we observed the decrease of all symptoms and the left ventricular size and function normalized (EF: 0.62). He has now been on oral carnitine for live. CONCLUSION: Primary carnitine deficiency is a cause of dilated cardiomyopathy in child. It must systematically be suspected when a child presents a primitive cardiomyopathy. The treatment with oral carnitine for live is simple, with excellent prognosis.

[A rare cause of arterial hypertension in children: Takayasu arteritis]. / Une cause exceptionnelle d'hypertension artérielle de l'enfant : l'artérite de Takayasu.

Takayasu arteritis, a nonspecific inflammatory arteritis, is particularly rare in children. We report the case of a 6-year-old girl presenting with severe arterial hypertension in the upper segment associated with an inflammatory syndrome. Investigations showed coarctation of the abdominal aorta at different levels, due to Takayasu arteritis. The patient was treated with percutaneous dilatation and stent implantation as well as prolonged anti-inflammatory therapy. Arterial hypertension in children needs to be investigated until its cause, which may be rare, such as Takaysu arteritis, is determined.

[Cardiac MRI in the follow-up of adult congenital cardiomyopathy patients]. / IRM cardiaque dans le suivi des cardiopathies congénitales à l'âge adulte.

Magnetic resonance imaging is a rapidly developing modality in cardiology. It offers an excellent image definition and a large field of view, allowing a more accurate morphological assessment of cardiac malformations. Due to its unique versatility and its ability to provide myocardial tissue characterization, cardiac magnetic resonance (CMR) is now recognized as a central imaging modality for a wide range of congenital heart diseases, including assessment of post-surgical cardiac anatomy, quantification of valvular disease and detection of myocardial ischemia. CMR provides useful diagnostic information without any radiation exposure, and improves the global management of patients with congenital heart disease.

Preoperative acidosis and infant development following surgery for congenital heart disease.

OBJECTIVE: Prenatal diagnosis has been shown to decrease pre-operative acidosis and might prevent the occurrence of disturbed developmental outcome. The aim of this study is to evaluate parameters for acidosis and their predictive value on developmental outcome in newborns with congenital heart disease. METHODS: A total of 117 patients requiring surgery for structural heart disease in the first 31 days of life were included. Diagnosis was established either pre- or postnatally. Preoperative values of lactate, pH and base excess levels were compared to the occurrence of disturbed developmental outcome, i.e. an underperformance of more than 10% on the P90 of a standardized Dutch developmental scale. Patients were divided into groups according to blood levels of acidosis parameters, using receiver operating characteristics curves to determine cut-off values for pH, base excess and lactate. RESULTS: No significant difference in developmental outcome was found using values for pH or base excess as a cut-off level. Preoperative lactate values exceeding 6.1 mmol/l resulted in a significant increase in impaired development compared to infants with a pre-operative lactate lower than 6.1 mmol/l: 40.9% vs 15.1% in (p=0.03). CONCLUSIONS: Pre-operative lactate values might have a prognostic value on developmental outcome in newborns with congenital heart disease. The limited prognostic value of pH can be explained by the fact that pH can be easily corrected, while lactate better reflects the total oxygen debt experienced by these patients.

Potential additional indicators for pacemaker requirement in isolated congenital atrioventricular block.

Low heart rate is the predominantly used indication for pacemaker intervention in patients with isolated congenital atrioventricular block (CAVB). The aim of this study was to compare the difference in heart rates recorded with ECG and Holter monitoring between paced (PM) and nonpaced (NPM) patients with isolated CAVB before pacemaker implantation to identify additional predictors for future PM need. Retrospective evaluation of atrial and ventricular rates (electrocardiography) and minimal and maximal (Holter) heart rates in 129 CAVB patients prior to PM implantation (n = 93) was performed, and results are expressed in V adjusted for age and sex. The average V score for the atrial rate was 0.51 (n = 50) in the PM group and 0.60 (n = 22) in the NPM group (not-significant). The average z score for the ventricular (average) rate was -0.91 (n = 83) in the PM group and -0.93 (n = 33) in the NPM group (not-significant). Minimal heart rate was -0.94 (n = 61) in the PM group and -0.86 (n = 25) in the NPM group (not significant). Maximal heart rate was -0.96 (n = 61) in the PM group and -0.95 (n = 26) in the NPM group (not significant). Initial recordings of the average heart rate and the minimal and maximal heart rate recorded during Holter monitoring do not seem to predict future pacemaker need in patients with CAVB. Studies with exercise stress tests are needed to confirm these findings.

[Transposition of the great arteries: long-term follow-up]. / Transposition des gros vaisseaux: suivi a long-terme.

The management of transposition of the great arteries has changed importantly over the last decades. New techniques are employed for the diagnosis and surgical intervention has improved. This has lead to an increasing number of long-term survivors, who require specialised and focussed follow-up, depending on their type of surgical repair Mustard/Senning of arterial Switch. The long-term problems vary for each type of repair and require a specific approach, pharmacotherapy, catheter intervention or surgery. These complex sequellae implicate that transposition patients are never completely cured and probably will have a limited life span.

[Treatment of congential heart disease with interventional catheterization]. / Traitement des cardiopathies congénitates par cathétérisme interventionnel.

The development in pediatric interventional cardiology has changed the therapeutic strategy for many patients with congenital heart disease. Interventional catheterization became the first choice for valvuloplasty, angioplasty and collateral vessel occlusion. Effective and safe transcatheter interventions exist for closure of atrial or ventricular septal defects and for patent ductus arteriosus. The progress in the technology used in the catheterization laboratory will permit to continue the expansion of the range of interventions performed without surgery. Pediatric cardiologists and congenital heart surgeons must understand each other's interventional techniques and how they can be used in a coordinated fashion. This interaction is essential for the optimal management of patients with both simple and complex congenital heart disease.

[Pediatrics. Advantages of prenatal diagnosis in congenital cardiopathies]. / Pédiatrie. Avantages du diagnostic prénatal dans les cardiopathies congénitales.

The diagnosis of a congenital heart disease can be made by fetal ultrasound as soon as the 12th week of pregnancy. The main indications for fetal echocardiography are maternal and fetal. Sequential approach is necessary to precise the anatomy and to elaborate a therapeutic strategy for that patient. For severe heart lesions delivery and postnatal care can be programmed, avoiding thus severe hypoxia and acidosis after birth. The prognosis of these children are thus much improved.

Treatment of fetal heart block with maternal steroid therapy: case report and review of the literature.

The presence of maternal autoantibodies to SS-A/Ro and/or SS-B/La is associated with the development of fetal heart block. There are data suggesting that maternal treatment with steroids might reverse heart block. We report on a pregnancy in a mother with secondary Sjögren syndrome and systemic lupus erythematosus with presence of autoantibodies to SS-A/Ro and SS-B/La, which was complicated by the development of incomplete fetal heart block. Oral dexamethasone treatment could not prevent progression to complete heart block and was associated with a number of complications.A review of the literature revealed 19 studies (including ours) in which 93 cases of fetal heart block were treated with maternal steroid therapy. Complete heart block proved irreversible in all cases; and of 13 fetuses with incomplete heart block which received maternal steroid therapy, three had a reduction in their degree of block and one reverted to sinus rhythm. Maternal steroid therapy, initiated early in pregnancy and potentially preventing the onset of heart block, did not decrease the incidence of heart block in nine studies with 43 cases. Furthermore, the literature review revealed numerous serious side effects of maternal steroid administration during pregnancy. Data on these potential side effects are lacking in the 28 studies discussed in this review. Maternal dexamethasone therapy to prevent or treat fetal heart block remains, in our opinion, a questionable intervention and can as yet not be recommended in the clinical situation.

Neurological outcome of children who were treated for fetal tachycardia complicated by hydrops.

OBJECTIVE: Fetal tachycardia is a condition associated with congestive heart failure and development of fetal hydrops, which may result in neurological morbidity and mortality. The aim of this study was to investigate the long-term outcome of hydropic fetuses. METHODS: This was a retrospective study on cognitive and neurological functioning of 11 infants, aged 6 months to 12 years, who experienced fetal tachycardia complicated by hydrops. RESULTS: Seven fetuses had supraventricular tachycardia (SVT), three had atrial flutter (AF) and one had ventricular tachycardia (VT). Nine fetuses converted to sinus rhythm within a mean time of 8.2 days of presentation; resolution of hydrops was achieved in six of these patients in a mean time of 8.8 days. Mean gestational age (GA) at birth was 35 + 4 weeks. Neonatal cranial ultrasound was normal in seven infants and all but one of these were normal at follow-up: one infant who initially had no abnormalities developed multiple cerebral lesions as a result of a malignant long QT syndrome (LQTS) and died at the age of 2 years. Three infants had periventricular echogenicity (PVE) on neonatal cranial ultrasound, associated with a pseudocyst in one infant. The remaining infant showed a parenchymal hemorrhage of antenatal onset, seen as a porencephalic cyst at birth. One of these infants was normal at follow-up, one died 2 days after birth and two infants had neurological abnormalities at follow-up, consisting of mild hemiplegia with normal cognitive function in one, and a cognitive developmental delay in the other. CONCLUSIONS: In this study, neurological outcome was good in eight out of 11 infants. Initiation of therapy should not be withheld or delayed on the assumption of poor neurological outcome.

Persistent junctional reciprocating tachycardia in the fetus.

BACKGROUND: Persistent junctional reciprocating tachycardia (PJRT) tends to be a persistent arrhythmia and requires aggressive therapeutic management. Diagnosis and management of this infrequently occurring tachycardia in the fetus at an early stage is of importance for the prevention of congestive heart failure (CHF). METHODS: A retrospective study of four fetuses with supraventricular tachycardia (SVT) of the PJRT type was performed. RESULTS: All had sustained SVT (mean of 228 beats/min) at a mean gestational age of 34 + 5 weeks, with CHF present in two. Three fetuses had prenatal characteristics of PJRT on M-mode echocardiography with a ventriculoatrial (VA)/atrioventricular ratio of > 1 on M-mode echocardiography suggesting a slow conducting accessory pathway. All four fetuses had postnatal confirmation of the diagnosis. Transplacental treatment with flecainide was effective in one patient; sotalol as a single drug or in combination with digoxin was partially effective in the remaining three. Two developed sinus rhythm, with short intermittent periods of tachycardia and decreasing signs of CHF; one case showed a minimal decrease in heart rate. Oral propranolol therapy converted two patients postnatally; in the remaining two patients radiofrequency ablation was performed at the age of 5 months and 6 years. CONCLUSIONS: The characteristics of our prenatal PJRT cases included a sustained heart rate not exceeding 240 beats/min with a long VA interval, the presence of CHF and therapy resistance. Transplacental treatment should be initiated, possibly with a combination of sotalol and digoxin in non-hydropic cases, or flecainide, especially in case of fetal hydrops. Pharmacological therapy is to be preferred postnatally, but radiofrequency ablation seems to be indicated in therapy-resistant cases with CHF, even in the first months of life.

Altered fetal circulation in type-1 diabetic pregnancies.

OBJECTIVE: Type-I diabetic pregnancies are associated with congenital cardiac malformations, fetal cardiomyopathy, venous thrombosis and altered placental vascularization, even with tight maternal glucose control. The aim of this study was to investigate if, with good glucose control achieved with continuous subcutaneous insulin infusion, normal blood flow within the fetal heart can be achieved. METHODS: Seventeen fetuses of women with well-controlled type-I diabetes were studied longitudinally to evaluate effects on the fetal circulation. Doppler frequency shift tracings, valve diameters and intercept angles were measured at right and left atrioventricular valve orifices at 4-week intervals starting at 15 weeks' gestation. Atrioventricular valve flow was calculated and compared to normal fetal data obtained in previous studies. RESULTS: Maximum and mean temporal velocities across the atrioventricular valves increased in both groups during gestation but significantly more in fetuses of type-I diabetic pregnancies. Combined ventricular output, both absolute and per kg estimated fetal weight, were also greater in these fetuses. In the normal group the ratio of the right/left ventricular output decreased significantly during gestation (from 1.34 +/- 0.28 to 1.08 +/- 0.28 standard deviations), but in type-I diabetic pregnancies this decrease did not occur (1.2 +/- 0.26 to 1.25 +/- 0.29 standard deviations)[corrected]. CONCLUSIONS: These data indicate that there are significant differences in the fetal circulation between normal pregnancy and well-controlled type-I diabetic pregnancy, suggesting the existence of a compensatory mechanism which increases fetal cardiac output and causes cardiac hypertrophy.

[Correlation between prenatal ultrasound diagnosis and findings from autopsies or neonatal operations due to structural congenital heart defects; a retrospective analysis]. / Samenhang van prenatale echografische diagnosen en bevindingen bij obductie of bij neonatale operatie wegens structurele congenitale hartafwijkingen; retrospectieve analyse.

OBJECTIVE: To determine the contribution of the prenatal ultrasound diagnosis of structural congenital heart defects to the care of patients requiring surgery for their condition in the neonatal period. DESIGN: Retrospective. METHOD: During the period January 1991-June 1999, data were collected from two groups of children. One group had a structural heart defect diagnosed prenatally and the other underwent a neonatal operation due to a heart defect. In the prenatal group, the management and follow-up were analysed, whilst in the surgery group, the extent to which ultrasound investigation had been performed and whether there was a relationship between prenatal diagnosis and the severity of acidosis were analysed. RESULTS: A structural heart defect was found through prenatal ultrasound in 170 children and 64% of these prenatally diagnosed patients died before or immediately after birth, or the pregnancy was aborted. 14% underwent surgery within 31 days post partum. This last category formed an overlap with the surgery group. The surgery group contained 191 patients, who required surgery in the neonatal period, including 24 from the prenatal group. In total, 87% had no prenatal diagnosis. In the group with a prenatal diagnosis pre-operative lactate values were significantly lower. CONCLUSION: The heart defect was only diagnosed prenatally in 13% of the patients from the surgery group, although this would have been technically feasible in 46%. Better prenatal diagnosis of heart disease could contribute to a better counselling of parents in their choice between abortion, conservative treatment or emergency surgery. In the case of emergency surgery, prenatal detection might lead to a decrease in morbidity and mortality.

[Congenital complete atrioventricular block in children: pathogenesis and clinical outcomes]. / Het congenitale complete atrioventriculaire blok bij kinderen: pathogenese en kliniek.

Congenital complete atrioventricular block (CCAVB) is induced by the placental transmission of maternal anti-SS-A/Ro and anti-SS-B/La antibodies during the second trimester of pregnancy where they cause inflammatory injury to the foetal heart. Anti-SS-A/Ro and anti-SS-B/La antibodies can be detected in most mothers of children with CCAVB. However, the chance of an antibody-positive woman giving birth to a child with CCAVB is 1-5% and the chance of this recurring is 16%. In addition to the maternal antibodies, foetal and environmental factors may also play a role in the pathogenesis. CCAVB is associated with high morbidity and mortality during the foetal and neonatal period. Pacemaker implantation is indicated in approximately 60% of these children, after the development of symptoms related to bradycardia, although the timing of this is controversial. The effectiveness of therapeutic intervention in the uterus has yet to be determined. A conservative approach is advisable with respect to the use of corticosteroids.

Endocardial and epicardial steroid lead pacing in the neonatal and paediatric age group.

AIM: To compare the performance of steroid eluting epicardial and endocardial leads in infants and children requiring permanent pacing. METHODS: Evaluation of pacing and sensing characteristics, impedances, and longevity of 159 steroid eluting leads implanted in 95 children. Group A consisted of 24 children weighing less than 15 kg with 15 endocardial leads (five atrial, 10 ventricular) and 19 epicardial leads (five atrial, 14 ventricular). Group B consisted of 71 children weighing more than 15 kg with 106 endocardial leads (56 atrial, 58 ventricular) and 19 epicardial leads (nine atrial, 10 ventricular). RESULTS: Group A: Stimulation thresholds were lower for ventricular endocardial leads at implant (mean (SD) 0.84 (0.54) v 1.59 (0.64) V, p < 0.014) and at two year follow up (ventricular 0.64 (0.24) v 1.65 (0.69) V, p < 0.003). Impedance and sensing thresholds did not differ significantly at implant and follow up. Group B: Stimulation thresholds were lower for ventricular endocardial leads at implant (0.72 (0.48) v 1.48 (0.58) V, p < 0.001) and at follow up (0.88 (0.46) v 1.55 (0.96) V, p < 0.009). Impedance did not differ. Sensing thresholds were also better for ventricular endocardial leads at follow up (9.1 (5.2) v 14.2 (6.4) mV, p < 0.02). Complications requiring intervention occurred in both groups (n = 7 for endocardial v n = 18 for epicardial leads). CONCLUSIONS: Endocardial and epicardial steroid eluting leads have comparable performance in the paediatric population.

Twenty-five years' experience with the arterial switch operation.

OBJECTIVE: The arterial switch operation was introduced in 1976 to correct transposition of the great arteries and has since replaced atrial palliation. This study examines the long-term outcomes of the arterial switch operation. METHODS: Included in the study were 195 patients who underwent the arterial switch operation from 1977 through June 2000. Patients were evaluated for functional class, pulmonary stenosis, left ventricular function, arrhythmias, aortic sequelae, and coronary disease. RESULTS: Overall perioperative mortality was 15%, but rates dropped in the last 5 years to 4% for complex transposition and 0% for simple transposition. Of 151 survivors, 2 died late; 1 died of persisting pulmonary hypertension and 1 died of ventricular fibrillation after coronary pathologic changes. At last follow-up, a total of 145 patients were in New York Heart Association functional class I and 4 patients were in class II. The most frequent complication was pulmonary stenosis, necessitating 45 reinterventions in 26 patients. Left ventricular dysfunction was noted in 5 patients. Arrhythmias were seen in 5 patients: 2 patients had ventricular fibrillation (1 died and 1 required a defibrillator implantation), 1 had sick sinus syndrome, 1 had atrial flutter, and 1 had a single attack of supraventricular tachycardia. Aortic valve incompetence was absent or trivial in 146 patients, 3 had mild incompetence, 1 had moderate incompetence, and 1 had severe incompetence. Coronary sequelae were found in 5 of the 61 patients who underwent angiography. CONCLUSION: Long-term clinical outcome of the arterial switch operation is good, and perioperative mortality is now low. Morbidity is dominated by pulmonary stenosis and coronary artery disease, with the potential for lethal arrhythmias.

Clinical implications of fetal magnetocardiography.

OBJECTIVES: To test the usefulness and reliability of fetal magnetocardiography as a diagnostic or screening tool, both for fetuses with arrhythmias as well as for fetuses with a congenital heart defect. METHODS: We describe 21 women with either a fetal arrhythmia or a congenital heart defect discovered during prenatal evaluation by sonography. Four fetuses showed a complete atrioventricular block, two an atrial flutter, nine ventricular extrasystole, and one a complete irregular heart rate. Five fetuses were suspected to have a congenital heart defect. In all cases magnetocardiograms were recorded. RESULTS: Nine fetuses with extrasystole showed a range of premature atrial contractions, premature junctional beats or premature ventricular contractions. Two fetuses with atrial flutter showed typical flutter waves and four fetuses with complete atrioventricular block showed an uncoupling of P-wave and QRS complex. One fetus showed a pattern suggestive of a bundle branch block. In three of four fetuses with confirmed congenital heart defects the magnetocardiogram showed abnormalities. CONCLUSION: Fetal magnetocardiography allows an insight into the electrophysiological aspects of the fetal heart, is accurate in the classification of fetal arrhythmias, and shows potential as a tool in defining a population at risk for congenital heart defects.

Lactacidosis in the neonate is minimized by prenatal detection of congenital heart disease.

OBJECTIVES: To investigate the impact of prenatal detection of congenital heart disease on preventing severe preoperative lactacidosis. DESIGN: Patients operated upon for congenital heart disease during the first 31 days of life (n = 209) were studied retrospectively, 21 were diagnosed prenatally and 188 patients had not been diagnosed prenatally. Preoperative lactate, pH and base excess were evaluated. RESULTS: Differences were noted in preoperative pH (7.28 +/- 0.03 vs. 7.24 +/- 0.01, P = 0.29), base excess (-5.83 +/- 0.64 vs. -6.93 +/- 0.46 mmol/L, P = 0.10) and lactate (3.05 +/- 0.35 vs. 6.08 +/- 0.45 mmol/L, P < 0.001), indicating a significant difference in blood lactate values in favor of the prenatally diagnosed group. CONCLUSIONS: Prenatal diagnosis of congenital heart disease and the resulting immediate postnatal care prevent lactate increase in the preoperative period of these patients. This may decrease the risk of cerebral damage and result in the patient being in better condition at surgery.