Cross-sectional echocardiography was performed on 108 healthy children (7 days – 17 years old) and 55 children (6 months - 16.5 years old) with interatrial communication. Right ventricular end-diastolic volume, end-systolic volume, stroke volume, ejection fraction, muscle volume, and the ratio of muscle to cavity were calculated on the basis of outlined cavity and myocardium of an apical fourchamber view.

In the normal subjects right ventricular end-diastolic volume, end-systolic volume, stroke volume and muscle volume correlated with body surface area (end-diastolic volume: y=12.5x+7.8x2, r=0.99; end-systolic volume: y=4.8x+3.6x2, r=0.98; stroke volume: y=7.7x+4.2x2, r=0.98; muscle volume: y=14.1x+2.9x2, r=0.97), muscle/cavity ratio (0.85±0.17) and ejection fraction (58.9 ± 6.2%) were unrelated to body surface area. In the subjects with interatrial communication, the right ventricular volumes were significantly larger (p<0.001) than the normal values with a linear relationship to the ratio of pulmonary to systemic flows.

Right ventricular volumes can be determined in normal children with acceptable repeatability using a standard apical four-chamber view. The growth related normal values provide a basis for future quantitative studies.