[Percutaneous dilatation of the pulmonary tract in tetralogy of Fallot].

When palliative treatment is indicated in tetralogy of Fallot, percutaneous endoluminal dilatation of the valvular pulmonary stenosis may represent an alternative to palliative surgery (systemico-pulmonary shunt) and its disadvantages. This paper sets out the clinical outcome and growth of the pulmonary arterial circulation after dilatation of the valvular pulmonary stenosis in children with tetralogy of Fallot. Twenty-five children (average age: 8 +/- 5.8 week; average weight: 6.7 +/- 2.4 kg) were included in this study. The dilatation resulted in an immediate decrease in the patients' cyanosis and a significant increase (+10%) in arterial oxygen saturation. However, this technique did not suppress the risk of anoxic malaise. Only 5 children (20%) required a palliative surgical shunt for persistence of anoxic malaise. From the anatomical point of view, the dilatation induced significant growth of the pulmonary annulus (7.6 mm vs 11.3 mm; p < 0.0001), of the main pulmonary artery (6.8 mm vs 10 mm); p = 0.008) and left pulmonary artery (7 mm vs 11 mm; p = 0.02). The need for a procedure to widen the right ventricular outflow tract at the time of complete correction was also reduced. The perioperative mortality of complete correction and postoperative pulmonary insufficiency were decreased. Percutaneous dilatation of the right ventricular outflow tract is therefore a valuable palliative alternative to surgical sytemico-pulmonary shunt.