The following echocardiographic changes were found in 42 patients with catheterization data for tricuspid insufficiency: all echocardiographic dimensions of the right ventricle and right auricle are considerably increased; the interventricular septum reveals paradoxical movements in 38 per cent of the cases; the tricuspid echogram shows unspecific changes in the speed and amplitude parameters of the anterior tricuspid cusp--increased speed (D--E) and amplitude (C--E) of opening, increased speed of backward movement in an early diastole (E-F), increased speed of closing (A--C),increased duration of the final diastolic intervals A--C and Q--C, the difference between the Q--C interval duration of the tricuspidal valve and Q--C interval of the mitral echogram is pathologically increased, the ratio between the speed of E--F segment of the tricuspid valve and E--F segment of the mitral valve is also increased. The diagnostic sensitivity of those changes of the tricuspid echogram is about 75 per cent. EchoC-diagnosis of the tricuspid insufficiency is based on the combination of considerably increased EchoC-dimensions of the right ventricle and the right auricle, paradoxical movements of the interventricular septum and the changes of the speed and amplitude parameters of the tricuspid echogram.