[Mitral valve replacement in atrioventricular septal defect]. / Remplacement valvulaire mitral dans le canal atrio-ventriculaire.

This study reports the cases of 14 patients aged 5 months to 13 years (average: 3.5 years) at the time of the initial repair of an atrioventricular septal defect (AVSD). The AVSD was partial in 5 and complete in the other 9 cases. After failure of the initial mitral valvuloplasty, the patients underwent mitral valve replacement with a prosthesis at the age of 1 to 29 years, after an interval of 0 days to 15 years. A second valvuloplasty had been attempted in 3 cases beforehand. The aim of this paper was to analyse the causes of failure of mitral valvuloplasty and to determine the conditions of mitral valve replacement and the specific complications of this type of surgery. Failure of mitral valvuloplasty was related to complex valvular malformations (5 cases), technically inadequate valvuloplasty procedures (4 cases), deterioration of an initially satisfactory valvuloplasty (5 cases). Four bioprostheses were implanted (repeat valvular replacement was necessary in 3 patients). Early mortality was 28% (4 patients). The postoperative complications specific to this condition were: immediate atrioventricular block (8 cases) but only 1 persistant complete atrioventricular block; traumatic fistula between the left ventricle and right atrium (4 cases); moderate stenosis of the left ventricular outflow tract (4 cases). There was one late death (due to isolated cardiac arrhythmia).(ABSTRACT TRUNCATED AT 250 WORDS)

[Ventricular dysplasia. Nosology and sudden death]. / La dysplasie ventriculaire. Nosologie et mort subite.

The arrhythmia generating dysplasia of the right ventricle is a congenital anomaly suggesting a hereditary substratum. It usually manifests itself as follows: a young patient, with recurrent episodes of ventricular tachycardiac. There is no "pathognomonic sign" of dysplasia. The latter may only be determined by anatomical examination of the heart, macroscopically as well as microscopically. The most difficult differential diagnosis concerns minor or localized forms of dilated idiopathic myocardiopathy or sequelae of myocarditis with ventricular tachycardia originating in the right ventricle. It seems, currently, more appropriate to talk about "arrhythmia generating syndrome of the right ventricle" rather than arrhythmia generating dysplasia of the right ventricle, in these particular cases. The arrhythmia generating syndrome of the right ventricle could cause a sudden death in these young patients, especially during a violent physical exercise or practise of sports. The current nosological classification is based on an experience acquired by comparing a few isolated cases. The search for late potentials by summation-mean measurements and nuclear magnetic resonance could provide a new diagnostic approach.