Contrast harmonic color Doppler left ventriculography: Machine-interpretedleft ventricular ejection fraction compared with equilibrium-gated radionuclide ventriculography

Background: Multi-gated acquisition (equilibrium-gated radionuclide ventric ulography) (MUGA) is considered the gold standard for measuring left ventri cular ejection fraction (LVEF) because it is accurate, machine interpreted, and reproducible. Echocardiographic LVEF measurements are subject to varia bility in image acquisition and interpretation and to the limitations of 2- dimensional (2D) versus 3-dimensional imaging. Goal: The shortcomings of traditional echocardiography may be addressed by combining multiplane 2D harmonic imaging, echocardiographic contrast, color Doppler ultrasonography, and digital image processing to create a new imag ing modality: contrast harmonic color Doppler left ventriculography. Methods: We compared the accuracy of a new method for measuring LVEF that a llows for machine interpretation and uses contrast-enhanced intermittent ha rmonic color Doppler ultrasonography (CHCD). Quantitative LVEF measurements by hand-traced harmonic 2D echocardiography, contrast-enhanced harmonic 2D echocardiography, CHCD, and machine-interpreted CHCD were compared with MU GA in 35 patients. Results: Contrast-enhanced intermittent harmonic color Doppler provided ima ges with vivid endocardial definition in all patients, but hand-traced harm onic 2D echocardiography and contrast-enhanced harmonic 2D echocardiography had inadequate images in 9% of patients. The MUGA LVEF range was 0.09 to 0 .70. All echocardiographic methods showed excellent correlation with the MU GA LVEF (R-2 > 0.96), but the CHCD method had the best limits of agreement. Conclusions: Contrast-enhanced intermittent harmonic color Doppler LVEF cor relates with MUGA at least as well as traditional noncontrasted echocardiog raphy, but it provides diagnostic images hr a greater proportion of patient s. The CHCD images have vivid endocardial delineation and can be machine in terpreted.