[Arrhythmogenic dysplasia of the right ventricle in a 16-month-old child]. / Dysplasie arythmogène du ventricule droit chez un enfant de 16 mois.

The clinical history of a 16-month old child with an arrhythmogenic right ventricular dysplasia is reported. This is one of the youngest patients described in the literature. The pitfalls of the diagnosis and the particularities of the treatment of recurrent ventricular tachycardias are underlined.

[Congenital heart diseases and obstructive pulmonary vascular diseases in Down's syndrome. Apropos of 142 children with trisomy 21]. / Cardiopathies congénitales et maladie vasculaire obstructive pulmonaire dans le syndrome de Down.

Trisomy 21 accounts for 3 p. 100 of reasons for admission to the Paediatric Cardiology unit of the St Luc University Clinics, Brussels. In a series of 142 cardiac children with trisomy 21 evaluated by catheterization between 1969 and 1987, 54 p. 100 of the cardiac malformations observed consisted of persistent common atrioventricular canal (complete in 45 p. 100 of the cases). The other heart diseases were ventricular septal defect (23 p. 100), atrial septal defect of the ostium secundum type (10 p. 100) and tetralogy of Fallot (9 p. 100). In 40 p. 100 of the patients other cardiovascular abnormalities were associated with these predominant intracardiac shunts. These findings were in agreement with those usually reported in the literature. At the time of investigation (mean age 24 months), pulmonary vascular resistance had already reached a pathological level in 88 p. 100 of the cases. Oxygen tests only slightly improved these results, which suggested that the conditions were favourable to the early development of a pulmonary obstructive vascular disease in Down's syndrome, thus darkening the prognosis of congenital heart disease in mongoloid children. In this series to overall mortality rate of corrective surgery was 23 p. 100. The risk was maximum in infants aged less than 3 months with severe and rapidly symptomatic lesions. The outcome in patients successfully operated upon was satisfactory, with benign residual lesions.(ABSTRACT TRUNCATED AT 250 WORDS)

[Severe hypertrophic myocardiopathy in newborn infants. Intra-erythrocyte calcium and the effect of lidoflazine, a calcium-channel inhibitor. Apropos of 2 cases]. / Myocardiopathie hypertrophique sévère du nouveau-né. Calcium intra-érythrocytaire et effet de la lidoflazine, inhibiteur d'entrée calcique. A propos de deux cas.

Two cases of severe hypertrophic obstructive cardiomyopathy in the neonate are reported. The first case was poorly tolerated because of predominant stenosis of the right ventricular outflow tract causing right to left shunting through a patent foramen ovale. The second case presented with severe syncope at 6 weeks of age. The first patient was treated with propranolol without any success. Regression of the clinical and electrocardiographic signs was obtained in both cases with lidoflazine, within a few weeks. Red blood cell calcium concentrations were abnormally high in both patients before treatment and returned to normal levels with clinical and echocardiographic improvement. Abnormal accumulation of intracellular calcium in the myocardium is a possible mechanism of this cardiomyopathy. The relation between this type of accumulation and the effects of catecholamine discharge are recalled. The possible initiating role of an enzymatic abnormality of calcium entry is discussed: the chaotic geometric alignment of the myocardial fibres, characteristic of this type of hypertrophy, would therefore be a secondary phenomenon. Once constituted, the hypertrophy would then become irreversible. However, it may be possible to reverse it in the neonate by calcium antagonists as suggested by these two cases.

Precocity of pulmonary vascular obstruction of Down's syndrome.

Studying the pulmonary vascular resistance in children with ventricular septal and endocardial cushion defects, the authors found a statistically significant earlier and more severe reaction in children with Down's syndrome as compared to normals. Cardiac investigations with regard to surgical intervention should be made early in life, if the parents wish their child with Down's syndrome to undergo surgery.