Doppler echocardiography is established as a useful method for detecting mitral regurgitation (MR). However, studies also show that Doppler echocardiography may be too sensitive for diagnosing pathologic MR. To determine whether the false-positive or clinically insignificant diagnosis of MR can be eliminated by defining more specific diagnostic criteria, pulsed Doppler findings were compared with left ventricular angiographic findings in 81 patients. Using the conventional Doppler criterion of any systolic increased spectral dispersion detected in the left atrium, sensitivity was 100% and specificity was 76%. Using holosystolic increased spectral dispersion as the criterion, sensitivity was 100% and specificity was 92%. Using the combined criteria of holosystolic increased spectral dispersion plus peak regurgitant blood flow velocity of greater than 150 cm/s, sensitivity was 100% and specificity was 97%. Doppler studies in 20 clinically normal persons showed that the combined Doppler criteria were 100% specific. In conclusion, the presence of holosystolic increased spectral dispersion within the left atrium with a peak regurgitant flow velocity greater than 150 cm/s appears to be as sensitive as and more specific than the presence of any systolic Doppler increased spectral dispersion in identifying patients with MR.