To confirm whether or not echocardiographic B-color images (temperature, magenta, rainbow) are superior to ordinary gray-scale images, 62 coronary artery disease (CAD) patients (42 men and 20 women) underwent gray-scale and B-color echocardiography and cineangiography within 24 hours. Left ventricular (LV) volume was derived from angiography using the single-plane area-length method and was derived from echocardiography using single-plane modified Simpson's formula. In predicting angiographic volume, the correlations between B-color images and angiography were similar to that between the gray-scale image and angiography. In evaluating LV ejection fraction, the correlation coefficients between B-color images and angiography (temperature r = 0.93, magenta r = 0.93, rainbow r = 0.92) were slightly higher than that between the gray-scale image and angiography (r = 0.85) (p less than 0.05). We conclude that B-color images yield estimates of LV volumes that are of similar accuracy to gray-scale images in patients with CAD.