Percutaneous pulmonary valvuloplasty has been used successfully in the treatment of pulmonary valve stenosis for several years, but reports on long-term results are still sparse. We have performed pulmonary valve balloon dilatation procedures 23 times in 22 patients since February 1985; the age of the patients ranged from 2 days to 22 years. Three patients did not benefit from the procedure, in two instances because the pulmonary valve was dysplastic and once because of severe associated infundibular stenosis. These patients subsequently underwent surgery. In the other 19 patients the initial transvalvular gradient of 35 to 160 mm Hg (mean 81 mm Hg) was markedly reduced (to values ranging from 10 to 60 mm Hg, mean 31 mm Hg) rendering surgery unnecessary. There were no complications. The patients have been followed up for periods ranging from 2 months to 3 years and all are asymptomatic. Repeat measurements of the transvalvular gradient were carried out either by recatheterization or by echo Doppler 4 months to 3 years after the procedure; we have not observed restenosis and the mean gradient remained unchanged compared to the measurements immediately after valvuloplasty. Pulmonary regurgitation was uncommon and indeed appears to be less prominent than after surgical valvotomy. Thus, percutaneous valvuloplasty now appears to be the preferred treatment for pulmonary valve stenosis and open heart surgery can be avoided in most cases.