Development of a technique for the complete correction of transposition of great vessels]

Complete transposition of the great arteries is one of the most common cardiovascular anomalies. Several surgical methods of treatment have been proposed. Arterial repair theoretically seems a better option since it does not introduce any additional intra cardiac anomaly and it restores the left ventricle to its natival systemic function. The rationale for neonatal arterial repair lies on fetal and neonatal cardiopulmonary physiology. The left ventricle has to eject immediately after surgery a normal cardiac output at systemic pressure in the aorta. This is the case in the neonatal period, because during fetal life pulmonary artery and aortic pressure are equal. For simple TGA, after birth, with the fall in pulmonary vascular resistances and constriction of the ductus arteriosus, pulmonary artery and left ventricular pressures drop dramatically to less than one third (1/3) of systemic pressure. As a result, the left ventricle is not stimulated for growth adaptation and becomes a thin ventricle less contractile and more compliant. However, there is little doubt that during the first 2 to 4 post-natal weeks, the left ventricle is still suitable to sustain a systemic workload. Between april 1984 and april 1992, four hundred and twenty six (426) consecutive neonates underwent an arterial switch operation for various forms of transposition: with 34 hospital deaths. The mean age at operation was 13 days and the mean weight was 3.2 kg. Among patients with TGA-VSD and coarctation, 14 underwent a single stage repair through mid sternotomy. Actuarial survival rates were: 89% for TGA-IVS at 5 years, 90% for TGA-VSD, 85.3% for TGA-VSD and coarctation at 3 years.(ABSTRACT TRUNCATED AT 250 WORDS)