INFLUENCE OF LEFT-VENTRICULAR DIASTOLE ON LEFT ATRIAL APPENDAGE BLOOD-FLOW IN PATIENTS WITH NONRHEUMATIC ATRIAL-FIBRILLATION

The function of the left atrial appendage (LAA) reflected by the Doppl er flow velocity at the outlet of the left atrial appendage has been r eported to be correlated with spontaneous echo contrast and thrombus f ormation. To evaluate the influence of left ventricular diastole on LA A flow during atrial fibrillation (AF), 81 patients with chronic nonrh eumatic AF were studied by transesophageal echocardiography. The peak outflow velocity of LAA during ventricular diastole was higher than th at during ventricular systole (0.23 +/- 0.14 vs. 0.15 +/- 0.13 m/s, p < 0.001), The peak inflow velocity of LAA during ventricular diastole was also higher than that during ventricular systole (0.22 +/- 0.15 vs , 0.18 +/- 0.11 m/s, p < 0.01). Patients with a good left ventricular ejection fraction have a significantly higher peak LAA outflow velocit y and a larger diastolic augmentation of LAA outflow (defined by the d ifference of LAA outflow between systolic and diastolic phases) than p atients with an impaired left ventricular function. Thus, left ventric ular diastole might have an influence on LAA flow during AF, In additi on, the left ventricular function might be considered a predictor of s ubsequent thromboembolism from the viewpoint of its effect on LAA flow in patients with nonrheumatic AF.