The presence and severity of valvular regurgitation were assessed retrospectively from review of a detailed Doppler echocardiographic data base. Valvular regurgitation, particularly of the mitral, tricuspid, and aortic valves, was reported if definite regurgitation was identified by any Doppler technique (particularly color-flow Doppler and continuous-wave Doppler, although occasionally with pulsed- Doppler evaluation for aortic regurgitation only). The following were general criteria for the evaluation of the severity of valvular regurgitation:
Mitral and Tricuspid Regurgitation: The severity of regurgitation was graded trivial, mild, moderate, or severe by comparing the dimensions of the color-flow jet with the dimensions of the atrial chamber in multiple orthogonal views.
Conventional Doppler gains were generally set near maximum, and color-flow gains were adjusted so that background artifact just disappeared. Pulse rate frequency varied and was adjusted automatically for depth by an internal algorithm. In general, a regurgitant jet area/atrial area of <10 percent was considered trivial, 10 percent to 25 percent was considered mild, 25 percent to 49 percent was considered moderate, and ^50 percent was considered severe. Qualitative assessment of central regurgitant jet areas consisted primarily of turbulent flow areas. In borderline cases, the severity grading of valvular regurgitation was influenced by the intensity of the continuous-wave regurgitant envelope. Because color-flow examination is excellent in the majority of patients, pulsed-wave Doppler is not routinely used in our laboratory for the detection of mitral or tricuspid regurgitation or assessment of its severity.