Echocardiographic determination of aortic and pulmonary valve areas in subjects with normal hearts
Related Experiment Videos
1Department of Pediatrics, University of Virginia Medical School, Charlottesville.
Insights
Echocardiography accurately measures aortic and pulmonary valve areas in children and adolescents. These valve areas correlate with body surface area, providing essential normal reference values for pediatric cardiology.
Area of Science:
- Pediatric Cardiology
- Echocardiography
- Cardiovascular Physiology
Background:
- Accurate assessment of aortic and pulmonary valve areas is crucial for diagnosing and managing pediatric heart conditions.
- Establishing normal reference values for valve areas in children is essential for clinical interpretation.
Purpose of the Study:
- To determine normal aortic and pulmonary valve areas in children and adolescents using echocardiography.
- To investigate the relationship between valve areas and body surface area in pediatric subjects.
Main Methods:
- Two-dimensional and Doppler echocardiography were performed in 70 healthy subjects (1 day to 16 years).
- Valve areas were calculated using the continuity equation, incorporating outflow tract diameters and Doppler-determined flow velocities.
- Measurements included left and right ventricular outflow tract diameters and velocities in the aorta and pulmonary artery.
Main Results:
- Outflow tract diameters showed a linear relationship with the square root of body surface area.
- Flow velocities in the outflow tracts and great arteries were independent of body size.
- Aortic and pulmonary valve areas demonstrated a linear correlation with body surface area (r=0.88 and r=0.80, respectively).
- Mean aortic and pulmonary valve area indexes were 1.33 cm²/m² and 1.70 cm²/m², respectively.
Conclusions:
- Echocardiography provides reliable measurements of aortic and pulmonary valve areas in children and adolescents.
- Indexing valve area to body surface area is a validated practice for establishing normal pediatric reference ranges.
- The study provides essential normal values for echocardiographically determined valve areas in the pediatric population.
Abstract:
Two-dimensional and Doppler echocardiography were performed in 70 subjects (aged 1 day to 16 years, body surface area from 0.08 to 2.1 m2) to determine aortic and pulmonary valve areas in normal children and adolescents. Valve areas were determined by the continuity equation using echo-determined ventricular outflow tract diameters and Doppler-determined flow velocities from the outflow tracts and corresponding great arteries. Left ventricular outflow tract diameter ranged from 0.3 to 2.2 cm and right ventricular outflow tract diameter from 0.4 to 2.8 cm. Outflow tract diameters were linearly related to the square root of body surface area. Flow velocity increased from a mean of 0.75 m/s in the left ventricular outflow tract to 1.12 m/s in the aorta and from 0.56 m/s in the right ventricular outflow tract to 0.89 m/s in the pulmonary artery. Flow velocities were unrelated to body size. Valve areas were linearly related to body surface area (r = 0.88 and 0.80 for the aortic and pulmonary valves, respectively). Mean aortic and pulmonary valve area indexes were 1.33 cm2/m2 and 1.70 cm2/m2, respectively. The data provide normal values for echocardiographically determined valve areas and validate the practice of indexing valve area for body surface area.