Pulmonary venous flow: its relationship to left atrial and mitral valve motion

The factors affecting pulmonary venous flow were studied in a group of 50 patients divided into four groups. Group 1 consisted of 14 normal subjects. Group 2 consisted of 10 patients with pure mitral stenosis and normal sinus rhythm. Group 3 consisted of 15 patients with pure mitral stenosis and atrial fibrillation. Group 4 consisted of 11 patients with atrial fibrillation alone. Pulmonary venous flow, atrial septal motion, and mitral valve flow were obtained by transesophageal echocardiography. Pulmonary wedge pressure or left atrial pressure was measured invasively in all patients. We observed that pulmonary venous flow had a reversed flow during atrial contraction and a biphasic flow in the ventricular phase. The first phase of flow occurred during ventricular systole, corresponding to the beginning of atrial relaxation. The second phase of flow, during ventricular diastole, occurred consistently after the rapid filling wave of mitral flow. The beginning of the second phase, corresponding to maximal relaxation of the atrial septum, reached a maximum corresponding to the beginning of atrial contraction. Results of the present study also indicate that decrease or absence of reversed atrial flow and decrease in the first phase of ventricular flow were noticeable in patients in Groups 2, 3, and 4. The second phase of pulmonary venous flow was significantly decreased in patients with mitral obstruction (Groups 2 and 3), but was maintained when the mitral valve was normal (Group 4). In six patients undergoing percutaneous mitral valvuloplasty, the ventricular phase of pulmonary venous flow increased.(ABSTRACT TRUNCATED AT 250 WORDS)