Pulsed Doppler evaluation of regurgitation in mitral valve prostheses.
Prosthetic mitral valve regurgitation was evaluated by both pulsed Doppler ultrasound and left ventriculography. Pulsed Doppler ultrasound was found to have only a 20% sensitivity in detecting prosthetic mitral valve regurgitation documented by left ventriculography. Possible reasons for this poor sensitivity include 1) an eccentric jet not identified by the small pulsed Doppler sample volume; 2) prosthesis interference with the Doppler signal in the apical four chamber view; and 3) the large angle of incidence between the pulsed Doppler signal and the regurgitant jet. Mitral insufficiency, especially when not severe, may be missed by this technique. Care must be taken in interpreting negative results from a pulsed Doppler ultrasound evaluation of a prosthetic mitral valve.