The aim of the paper was to investigate the right ventricle in paediatric dilated cardiomyopathy. We examined 11 patients with dilated cardiomyopathy as well as 12 normal paediatric controls. Cardiac magnetic resonance imaging was performed for ventricular size and function. N-terminal pro-brain natriuretic peptide was collected at this time and the results from the most recent echocardiogram and exercise test were reviewed.

We found that patients with dilated cardiomyopathy had significantly faster heart rates, that is, 85 versus 65 beats per minute, lower left ventricular ejection fraction, that is, 42 versus 61%, and right ventricular ejection fraction of 44 versus 54%, lower left and right ventricular stroke volumes, that is, 35.5 versus 49.5 millilitres per square metre and 40.9 versus 56.4 millilitres per square metre, respectively, and lower mitral and tricuspid valve inflow e/a wave velocity ratios of 2.02 versus 2.80 and 1.25 versus 2.58, respectively, than the controls. Tricuspid valve annulus velocity, measured by tissue Doppler echocardiography, correlated with right ventricular ejection fraction (r = 0.60, p = 0.05). Right ventricular ejection fraction and indexed right ventricular end-diastolic volume correlated with N-terminal pro-brain natriuretic peptide (r = −0.67, p = 0.03, r = 0.65, p = 0.04, respectively), and right ventricular ejection fraction correlated with the oxygen uptake at the anaerobic threshold (r = 0.67, p = 0.049). Neither left ventricular ejection fraction nor left ventricular volume correlated with N-terminal pro-brain natriuretic peptide or exercise tolerance. The right ventricular function is decreased in the early stages of dilated cardiomyopathy. Right ventricular size and ejection fraction may be important indicators of sub-clinical cardiac failure and we suggest monitoring them routinely in dilated cardiomyopathy.

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.