3-DIMENSIONAL ECHOCARDIOGRAPHIC ASSESSMENT OF RIGHT-VENTRICULAR VOLUME AND FUNCTION IN PATIENTS WITH PULMONARY-HYPERTENSION

The structural complexity of the right ventricle has made quantitative evaluation difficult. Conventional cross-sectional echocardiographic methods are limited by geometric assumptions and the position of the p lanes used for imaging. Previous reports have demonstrated accurate th ree-dimensional echocardiographic quantitation of the right ventricle in-vitro and in experimental animals. We adapted a previously describe d method for three-dimensional reconstruction of the left ventricle to compute right ventricular volume and ejection fraction in a clinical setting. We examined 29 patients aged from 2 to 42 years with pulmonar y hypertension, by three-dimensional echocardiography and resonance im aging. Correlation and agreement were calculated for volumes and eject ion fractions. Three-dimensional echocardiographic reconstruction, whe n compared to resonance imaging, yielded r values of 0.95 and 0.93, an d mean differences (bias) of 31% +/- 19% and 33% +/- 18%, for systolic and diastolic volumes respectively. Interobserver variability was low (12.9% and 8.0%). Ejection fraction as calculated by three-dimensiona l echocardiography showed close agreement with resonance images (bias= 1% +/- 7%). Three dimensional echocardiography is now a method of meas uring right ventricular ejection fraction in the clinical setting whic h produces results comparable to those of resonance imaging. Volume me asurements correlated well for systole and diastole, but consistently underestimated values produced from resonance images.