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Serial studies of pulmonary stenosis in infancy and childhood
Insights
Pulmonary stenosis in children can worsen with age, as the pulmonary valve may not grow sufficiently to match the heart's increased output. This can lead to right ventricular pressure increases and hypertrophy, sometimes masked by ECG changes.
Area of Science:
- Pediatric Cardiology
- Cardiovascular Physiology
Background:
- Pulmonary stenosis is a common congenital heart defect.
- Understanding its progression in children is crucial for management.
Purpose of the Study:
- To investigate the longitudinal changes in right ventricular pressure and pulmonary valve orifice area in children with pulmonary stenosis.
- To identify factors influencing the progression of pulmonary stenosis.
Main Methods:
- Cardiac catheterization was performed on 35 children (aged 1 day to 9 years) and repeated after 2 weeks to 15 years.
- Measurements included right ventricular systolic pressure and pulmonary valve orifice area indexed to body surface area.
Main Results:
- Right ventricular systolic pressure increased in 24 children, particularly those under 5 years old.
- Pulmonary valve orifice area decreased in 17 children, often associated with infundibular hypertrophy.
- The increase in right ventricular pressure was attributed to the valve orifice failing to grow proportionally with stroke volume.
- While overall right ventricular hypertrophy correlated with stenosis severity, individual ECGs could be misleading.
Conclusions:
- Pulmonary stenosis progression in children is influenced by the relative growth of the pulmonary valve orifice and the heart's stroke volume.
- Infundibular hypertrophy can contribute to reduced orifice area.
- Electrocardiographic findings may not always accurately reflect changes in right ventricular pressure in individual cases.
Abstract:
Thirty-five children with pulmonary stenosis were catheterized from 1 day to 9 years of age and recatheterized after 2 weeks to 15 years. Right ventricular systolic pressure rose in 24 and the increase was greater in those under than over 5 years old. Pulmonary valve orifice area per square metre of body surface area increased in 12, but did not change in 3, and fell in 17; absolute decrease in calculated orifice area was usually associated with infundibular hypertrophy. Increase in right ventricular systolic pressure with age was thus caused by failure of the valve orifice to grow fast enough to keep pace with the increase of stroke volume. In the whole group, increasingly severe pulmonary stenosis was matched by increasing electrocardiographic evidence of right ventricular hypertrophy. However, in individual patients the electrocardiogram could suggest that right ventricular pressure had decreased when in fact it had risen considerably.