Relationship of pulmonary venous flow pattern to mean left atrial pressure and phasic pressure change

To assess the correlation of pulmonary venous flow pattern with the magnitude of the dynamic change in left atrial pressure (i.e. x and y descents) and to elucidate the way how pulmonary venous flow pattern reflects left atrial pressure, we studied 35 patients with normal sinus rhythm undergoing transesophageal echocardiography and cardiac catheterization. The ratio of peak systolic/diastolic flow correlated well with the ratio of x/y descent (r = 0.88) and the ratio of systolic/diastolic velocity-time integral (r = 0.89). The correlation between the ratio of systolic/diastolic flow or velocity-time integral and mean atrial pressure was less strong (r = -0.49 and -0.70, respectively). We conclude that the ratio of peak systolic/diastolic flow velocity, or the ratio of systolic/diastolic velocity-time integral of pulmonary venous flow reflects the phasic change in left atrial pressure more appropriately than the mean left atrial pressure. Due to the good correlation between the phasic change in left atrial pressure and pulmonary venous flow pattern, the flow pattern of pulmonary veins could be used to identify diseases with specific patterns of left atrial pressure.