Posterior wall velocity determined by use of echocardiography has been proposed as an index of total left ventricular performance in patients with ischemic heart disease. Accordingly, in 9 normal subjects and 39 patients with angiographically documented coronary artery disease, we compared mean endocardial posterior wall velocity determined by echocardiography with echocardiographic and biplane cineangiographic calculations of ejection fraction and the mean rate of circumferential fiber shortening (mean VCF), and with externally recorded systolic time intervals. All studies were performed on the same day in each patient. Mean endocardial posterior wall velocity averaged 4.6 cm/sec (range 2.9 to 8.7) and correlated poorly with echocardiographic ejection fraction (r = 0.47), cineanglographic ejection fraction (r = 0.26), cineangiographic mean VCF (r = 0.47), the ratio of preejection period to left ventricular ejection time (r = -0.35) and the preejection period corrected for heart rate (r = -0.30). Substitution of maximal for mean endocardial posterior wall velocity did not improve the separation of normal from depressed left ventricular performance. Epicardial posterior wall velocity, a measurement more easily obtainable than endocardial posterior wall velocity, also did not correlate well with systolic time intervals or with ejection fraction or mean vcf derived from the echocardiogram and cineangiogram. Both endocardial and epicardial posterior wall velocity values were poorly reproducible on a day to day or a beat to beat basis. We conclude that neither endocardial nor epicardial posterior wall velocity, whether derived as a mean or a maximum, provides an accurate measure of total left ventricular performance in patients with coronary artery disease.