This work deals with transmitral flow studied with Range Gate Pulsed Doppler Echocardiography in a 73 year old man affected by left atrial myxoma. The dominant clinical picture was pleural effusion and dyspnoea. Neither syncope nor systemic emboli were reported. Echocardiography (TM and 2D) and surgical inspection showed a large moving tumor connected to the interatrial septum with a short stalk. The histological examination gave evidence of myxoma. Range Gate Pulsed Doppler Echocardiography, using the apical four chamber view, was performed with the sample volume between the mitral leaflets and tumor. Peak velocities were normal, indicating no diastolic a-v gradient, probably the size of the tumor interfered with left atrial filling. The flow between the anterior leaflet and tumor was only protodiastolic: the myxoma leaning on the leaflet just after the opening stopped the blood stream. The flow between the posterior leaflet and tumor was variable, with single or multiple velocity peaks (early, middle and end diastole): this was probably caused by the intermittent obstruction of the a-v ostium. These data agree with the variability of the auscultation in the left atrial myxoma and show that the flow pattern is different from that of mitral stenosis.