Natural history of congenital pulmonary valvar stenosis: an echo and Doppler cardiographic study.

Doppler echocardiography allows accurate serial assessment of pulmonary valvar stenosis by measuring the velocity of the jet stream through the pulmonary valve. Between 1979 and 1997, we saw 174 patients with isolated pulmonary valvar stenosis. At admission their ages ranged from 9 days to 22.5 years. We measured the velocity over the pulmonary valve, and the thickness of the anterior wall of the right ventricle, and made a study of their electrocardiograms. We found that rapid increases and decreases occurred in almost every age-group. For patients with a trivial, mild or moderate level of stenosis, severe stenosis developed in 3, 10 and 9%, respectively. In most of the patients, 122 (90%), in whom there was more than one examination, a change in pressure gradient between -12 mmHg/year and +3 mmHg/year was found. Only 7 patients had an increase of more than 10 mmHg per year. In contrast with our patients having aortic stenosis, these with stenosis of the pulmonary valve showed no rapid increase in early childhood. Indeed, in 58% the severity of the stenosis decreased. No correlation was found when comparing the echocardiographic measurements of the thickness of the anterior wall of the right ventricle with the voltages on the electrocardiogram. A significant relation was found however, between an increasing pressure gradient and thickened valvar leaflets (p=0.017).