Late (five to nine years) follow-up after balloon dilation of valvular pulmonary stenosis in adults.

The transvalvular gradient was investigated in 14 patients with pulmonary stenosis 5 to 9 years after balloon valvuloplasty. None of the patients had developed restenosis, and in those who had a peak gradient >100 mm Hg before valvuloplasty, the gradient decreased further due to resolution of subvalvular muscular hypertrophy within 3 months after intervention.