First clinical experiences with contrast Doppler echocardiography -- a new technique of cardiac ultrasound examination are described. The presence of contrast material within the right heart cavities following the peripheral vein injection is easily recognized by characteristic Doppler signal changes. This knowledge was used to detect a small amount of contrast passing through atrial (ASD) or ventricular septal defect (VSD) towards the left heart cavities despite the dominant left-to-right shunting. The high sensitivity of this technique in those conditions was attested to by correct diagnosis of 10 ASD and 3 VSD. Besides that, this technique is indicated also in selected cases of tricuspid regurgitation. The combination of both pulsed Doppler and contrast echo-investigation seems to be advantageous in the diagnosis of the mentioned diseases. However, further study of this very specialized method is required.