In 13 patients with isolated mitral stenosis in sinus rhythm the pulmonary venous flow was evaluated by transoesophageal pulsed Doppler echocardiography. The patients were divided into two groups according to their mitral valve area (MVA); Group I (MVA < 1.5 cm2, n = 7 patients); and Group II (MVA > 1.5 cm2, n = 6). The patients in group I with haemodynamically significant mitral stenosis had lower velocities of systolic (S), diastolic (D) and atrial retrograde (A) waves of pulmonary venous flow (PVF) compared to milder stenosis (P < 0.05). The peak velocity of pulmonary retrograde venous flow at atrial contraction (A) primarily depends on the relative amplitude of the atrial transmitral wave (RA), which is measured from the onset of atrial systole to its peak velocity. We found a highly positive correlation between RA of mitral valve flow (MVF) and A wave of PVF (r = 0.87, P < 0.0001). There was also a highly negative correlation (r = 0.80, P < 0.001) between A of PVF and ratio of early (PE) to late (PA) velocities of MVF. Therefore, the retrograde A wave of PVF is related to the pressure generated in the left atrium during atrial systole. Use of pulmonary vein velocities in conjunction with mitral flow velocities can increase our understanding of the haemodynamics of mitral stenosis and provide a new insight into left atrial performance.