Effect of atrial fibrillation on pulmonary venous flow patterns assessed by doppler transesophageal echocardiography

Study objectives: To investigate the effect of atrial fibrillation (AF) on pulmonary venous flow (PVF) patterns in a cohort with nonrheumatic AF. Design and settings: A prospective and controlled study undertaken at a tertiary referral medical center. Patients and measurements: The echocardiographic parameters of left superior PVF as assessed by Doppler transesophageal echocardiography in 40 patients with chronic AF (group 1) were compared to those of 33 volunteers with sinus rhythm (group 2) and well- matched baseline characteristics. Results: All group I patients presented with single systolic forward flow (SFF) patterns. In contrast, single and double SFF patterns were found equally in group 2. With regard to reverse flow (RF), most group I patients (33 of 40) had an early systolic RF and none had atrial RF; however, most group 2 subjects (29 of 33) had an atrial RF. Some of the group 1 patients (17%) had a late Systolic RF in the absence of significant mitral regurgitation. In group 1, the SFF appeared later and disappeared earlier than in group 2. The mean systolic peak velocity and time-velocity integral (TVI) of the SFF were significantly lower in group 1 compared to group 2. The diastolic peak velocity and TVI were not significantly different between groups. Conclusions: Our data indicate that AF independently and significantly affects the PVF and leads to characteristic flow patterns different from sinus rhythm. The presence of AF reduces SFF in addition to the absence of atrial RF. These changes in the flow patterns should be taken into account while interpreting the implications of PVF in the presence of AF.