A prospective comparison of continuous wave versus high pulse repetition frequency Doppler echocardiography for quantifying transvalvular pressure gradients in adults with aortic stenosis

To evaluate the relative accuracy of continous wave (CW) and high pulse repetition frequency (HPRF) Doppler for estimating aortic transvalvular pressure gradients, Doppler examinations with both devices were obtained in 87 consecutive patients with aortic valve disease. Thirty-seven (43%) also underwent catheterization and direct determination of the pressure gradient. The correlation between CW Doppler and catheterization measurements was high ( r = 0.91) and significantly superior to HPRF Doppler ( r = 0.72; p < 0.005). Disparities between the Doppler measurements predominantly occurred in patients with gradients exceeding 50 mm Hg in whom underestimation by the HPRF instrument was frequent. These data suggest that continuous wave Doppler is the preferred modality for the estimation of transvalvular pressure gradients in adult patients with moderate or severe aortic stenosis.