To develop a new method for measuring the right ventricular systolic function noninvasively, Doppler echocardiography (DE) and cardiac catheterization (CC) were simultaneously performed in 31 patients with tricuspid regurgitation (TR). The regurgitant velocities were recorded by the continuous-wave Doppler technique and converted into the instantaneous pressure gradients and right ventricular pressures using a modified Bernoulli equation. The uprising peak rate of the right ventricular pressure (IP) at the time point of dp/dt max and the ratio of dp/dt max/IP were calculated from both the pressure curves and Doppler spectra. The result showed that there were high correlations of dp/dt max, IP and dp/dt max/IP measured by DE and CC (r = 0.87, 0.89 and 0.89, respectively). The conclusion is that DE provides a feasible and reliable approach to the noninvasive estimation of the right ventricular systolic function in patients with TR.