Left ventricular volume was determined in 12 healthy volunteers using a newly developed two-dimensional echocardiographic delineation method. The results were compared with those of magnetic resonance imaging, which served as the method of reference. Left ventricular end-diastolic volume was 123 +/- 12 ml, echocardiographically defined, and 121 +/- 12 ml calculated with magnetic resonance imaging. End-systolic volume was 41 +/- 7 ml on echocardiography and 37 +/- 6 ml on magnetic resonance imaging. Left ventricular ejection fraction was 67 +/- 4%, echocardiographically defined, and 70 +/- 5%, calculated with magnetic resonance imaging. There was no statistical difference for any of the measured parameters. Interstudy and inter-observer variability was minimal. In conclusion, in healthy volunteers left ventricular volume was accurately defined, using this newly developed two-dimensional echocardiographic delineation method. During endocardial delineation a dynamic display is continuously available on a second window, allowing precise visual edge-detection. Moreover, corrections can be made easily and quickly. These two advantages enhance the accuracy of the method, even in cases of poor echogenicity.