Assessment of the peak tricuspid regurgitant velocity from the dynamics of retrograde flow.

We describe a simple, non-invasive and practical method to determine the peak velocity of tricuspid regurgitant flow (and hence derive systolic pulmonary artery pressure) from examination of the dynamics of retrograde tricuspid flow on Doppler. Based on a previously described relationship between right ventricular systolic pressure and the time interval between pulmonary valve closure and tricuspid valve opening, our technique does not require the peak tricuspid regurgitant velocity to be recorded; nor, as in previous studies does it rely upon recording the jugular venous pulse, right ventricular apexcardiogram or invasive pressure measurements. We have studied 65 patients with right ventricular disease (53 with pulmonary hypertension), and 24 with dilated cardiomyopathy, with M-mode, two-dimensional echocardiography, Doppler, and phonocardiography. The peak tricuspid regurgitant velocity could be predicted from the interval between pulmonary closure and the end of the tricuspid regurgitant signal on Doppler in patients with pulmonary hypertension and those with right ventricular disease with normal pulmonary artery pressure, but not in patients with dilated cardiomyopathy. In patients with pulmonary hypertension or right ventricular dilatation, this may be a useful alternative method in estimating pulmonary artery pressure from Doppler, in cases where it is not possible to record the peak tricuspid regurgitant velocity.