Three-dimensional Doppler. Techniques and clinical applications.

Abstract

Colour Doppler is the most widely used technique for assessing valve disease, but eccentric regurgitant jets cannot be visualized and measured by conventional 2D techniques. We have developed a new procedure for three-dimensional (3D) reconstruction of colour Doppler signals. Fifty patients with mitral regurgitation underwent transoesophageal echocardiography and 3D acquisition. The severity of mitral regurgitation was assessed by angiography and the regurgitant volumes were measured by pulsed Doppler. The jet areas were calculated by planimetry from conventional colour Doppler; the jet volumes were obtained by 3D Doppler. A higher degree of mitral regurgitation was found in the patients with eccentric jets. While jet areas showed poor correlation with regurgitant volumes (r = 0.61), jet volumes correlated significantly with regurgitant volumes (r = 0.93; P < 0.001). While jet areas failed to identify patients with different grades of regurgitation, jet volumes could so discriminate. 3D Doppler revealed new patterns of regurgitant flow and allowed a more accurate semiquantitative assessment of complex asymmetrical regurgitant jets. Three-dimensional colour Doppler has a great potential for becoming a reference method for the assessment of patients with heart valve disease.