Determination of atrial size by esophageal echocardiography.

The sizes of both left atrial (LA) and right atrial (RA) cavities were assessed in 16 patients by esophageal echocardiography and biplane cineangiography. The changes in echocardiographic dimension and cineangiographic volume during 1 cardiac cycle showed excellent correlations in both atria. In the left atrium, the relation between the echocardiographic dimension and the cineangiographic volume was significant (r = 0.83) and was fitted by the following power function: LA volume (ml) = 0.94 X LA dimension (mm) 1.24. In the right atrium, the relation between the dimension and the volume was significant; RA volume (ml) = 0.015 X RA dimension (mm) 2.34 (r = 0.95). Thus, esophageal echocardiography is a useful method for evaluating LA and RA size and simultaneously observing of both atria.