OBJECTIVE To examine the use of Doppler echocardiography in preoperative assessment of aortic stenosis and to determine its effect on subsequent use of hemodynamic cardiac catheterization. METHODS We retrospectively reviewed a consecutive series of 574 adult patients who underwent aortic valve replacement for aortic stenosis between 1990 and 1992 at our institution. The use of Doppler echocardiography and cardiac catheterization and the predictive factors for use of hemodynamic catheterization were analyzed. RESULTS After Doppler echocardiography in 423 patients, invasive hemodynamic assessment of the severity of aortic stenosis was performed in only 42% (179 patients). The use of cardiac catheterization declined over time (54% in 1990, 40% in 1991, and 35% in 1992) (P = 0.003), whereas no significant change in the baseline clinical characteristics of the population or in severity of stenosis as determined by Doppler echocardiography occurred during that time. Multivariate analysis identified the following variables as independent predictors of use of cardiac catheterization after Doppler echocardiography: clinically not severe aortic stenosis, mean gradient of less than 50 mm Hg determined by Doppler echocardiography, Doppler-determined aortic valve area of more than 0.8 cm2 or not calculated, attending cardiologist not specialized in echocardiography, and earlier year of assessment. CONCLUSIONS After Doppler echocardiography, less than 50% of our patients undergoing aortic valve replacement for aortic stenosis have cardiac catheterization preoperatively. The use of cardiac catheterization after Doppler echocardiography--thus, duplication of hemodynamic assessment--declined significantly over time during the study period. Decline in the use of catheterization is related to the degree of diagnostic certainty provided by Doppler echocardiography and to the level of familiarity of the attending cardiologist with the technique.