[Percutaneous transluminal valvuloplasty in pulmonary stenosis. Apropos of 24 cases].

Twenty-four patients with moderate or severe valvular pulmonary stenosis were treated by percutaneous transluminal valvuloplasty (PTV). The age of the patients ranged from 24 hours to 27 years. Eighteen patients (group I) had a right ventricle-pulmonary artery (RV-PA) pressure gradient greater than 50 mmHg (measured simultaneously or during catheter withdrawal). Six patients (group II) had RV-PA pre-sure gradients of less than 50 mmHg. Twenty-seven PTV procedures were performed. Six of the 24 patients were under 2 months of age, including 4 who were less than 1 week old. The youngest patient (under 24 hours old) had valvular pulmonary stenosis, very nearly atresia. PTV was carried out using Rashkind's technique on 2 occasions and with a dilatation catheter with a balloon of 6 to 20 mm of diameter on the other 25 occasions. In 6 cases, 2 dilatation catheters were introduced and inflated simultaneously in the pulmonary valve. The overall results were satisfactory: RV pressure fell from 87.6 to 54.4 mmHg, the RV-PA gradient from 72.3 to 31.9 mmHg and the ratio of RV/systemic pressure from 104.4 to 51.1. The improvement was more marked in group I than in group II. The causes of failure are discussed: valvular dysplasia, severe infundibular hypertrophy, inadequate diameter of the balloon. Tolerance of PTV was very good. The value of this procedure is emphasised. It may save surgical valvotomy in high risk groups of patients, such as the newborn and infants. The haemodynamic results of PTV are maintained at long-term, but the number of cases is still too small.