Echocardiographic study of the left auricular function and its influence on left ventricular performance in normal and diseased heart. I. Normal subjects.

Despite some limitations of the echocardiographic estimation of ventricular volume, previous studies have proved its utility in clinical practice. Assuming that the variation of ventricular volume during atrial contraction represents the atrial output, we have tried to study atrial function, its variations and its contribution to ventricular function in physiological states. For this purpose, an echocardiogram of good quality was recorded in 60 normal African subjects, mean age: 26.5 +/- 9.2. Various atrial parameters were derived from the echocardiographic dimension. Correlation was good between these indexes and the time parameters with the highest value for heart rate and the percentage of total diastolic duration of the auriculo-ventricular conduction. In order to test atrial contribution to ventricular function, ventricular and auricular indexes were correlated. Atrial systolic volume (ASV), calculated as the difference between end diastolic volume and preauricular volume on the left ventricular echocardiogram, and atrial index (ASV/BSA), have been found to have a good correlation with the ventricular stroke volume and cardiac index.