[Study on tricuspid regurgitation in Ebstein's anomaly using pulsed Doppler technique combined with two-dimensional echocardiography].

To investigate the localization of tricuspid regurgitant flow in Ebstein's anomaly, pulsed Doppler echocardiography (PDE) was performed on nine patients with or without associated cardiac lesions. The equipment used was characterized by the real time frequency analysis of Doppler signals obtained from the sampling sites confirmed on the cross-sectional images. We employed the apical four-chamber view or right ventricular inflow view in order to facilitate the sampling of Doppler signals from the three-sided heart chambers of this lesion. Doppler signals were recorded from several points in the functional right ventricle, atrialized right ventricle and right atrium. The PDE recording was made in conjunction with M-mode echocardiography at a paper speed of 50 mm per second. In eight of the nine patients, a systolic disturbed flow of wide band pattern was maximally located in the atrialized right ventricle in the vicinity of the tricuspid valve leaflets and had a delayed onset, which were seemed to be the findings characteristic of tricuspid regurgitation in Ebstein's anomaly. In the remaining one, a turbulent flow due to this lesion was obscured by a systolic jet of the associated ventricular septal defect in the vicinity of the tricuspid valve leaflet. In the right atrium, no disturbed flow of wide band pattern existed or only a faint abnormal blood flow was observed during systole. In the functional right ventricle, a smooth blood flow of the right ventricular inflow was recognized in diastole. In contrast, 15 patients with secondary tricuspid regurgitation revealed a holosystolic disturbed flow of wide band pattern maximally in the right atrium in the vicinity of the tricuspid valve leaflets. In eight healthy subjects, there was no systolic disturbed flow in the right atrium. Pulsed Doppler technique combined with two-dimensional echocardiography is thought useful to detect the localization of the disturbed flow in Ebstein's anomaly, thus contributing to the differentiation of various causes of tricuspid regurgitation.