Right atrial appendage function in patients with chronic nonvalvular atrial fibrillation

To assess right atrial appendage (RAA) flow and its possible relationship t o left atrial appendage (LAA) flow in chronic nonvalvular atrial fibrillati on (AF), transesophageal echocardiography (TEE) was performed in 26 patient s with chronic nonvalvular AF (group I). For the purpose of comparison, an additional group of 27 patients with chronic valvular AF due to mitral sten osis (group II) was analyzed. The clinically estimated duration of AF in gr oup I was significantly longer than that of group II (8.7 +/- 3.4 versus 2. 7 +/- 1.1 years). Although right atrial size and RAA maximal area were larg er in group I than those in group II, left atrial size was larger in group II than that in group I. Group II had larger LAA maximal areas than group I , but this difference did not reach statistical significance. The two group s were not different with respect to the RAA or LAA emptying velocities. Si gnificant correlations were observed between echocardiographic parameters o f the two atria in patients with nonvalvular AF (r range, 0.4 to 0.7). In c ontrast, in patients with valvular AF, no correlation was observed between the echocardiographic parameters of the two atria (appendage emptying veloc ity, r = 0.38, p = 0.051; atrial size, r = - 0.03, p = 0.89; maximal append age area, r = 0.07, p = 0.75, respectively). There were no significant diff erences in the presence of right and left atrial spontaneous echo contrast and thrombus between the groups. All of the right and left atrial thrombi w ere confined to their respective appendages and were found in the atria wit h spentaneous echo contrast. Both RAA and LAA thrombi were present in one p atient. In conclusion, our findings suggest that AF could affect both atria equally in nonvalvular AF, in contrast to valvular AF. Therefore, the asse ssment of RAA function as well as LAA may be important in patients with chr onic nonvalvular AF.