[Mitral valve replacement in atrioventricular septal defect].

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)