DOI: 10.1111/j.1540-8175.2009.01027.x C  2010, Wiley Periodicals, Inc. Right Atrial Appendage Function in Different Etiologies of Permanent Atrial Fibrillation: A Transesophageal Echocardiography and Tissue Doppler Imaging Study Tayfun Sahin, M.D., Dilek Ural, M.D., Teoman Kilic, M.D., Ulas Bildirici, M.D., Guliz Kozdag, M.D., Aysen Agacdiken, M.D., and Ertan Ural, M.D. Kocaeli University Medical Faculty, Department of Cardiology, Kocaeli, Turkey Objectives: Several studies exist on the left atrial appendage function (LAA) in permanent atrial fibrillation (AF). However, knowledge about the right atrial appendage (RAA) function is limited. We investigated RAA function with TEE and tissue Doppler imaging (TDI) in permanent AF patients with different etiologies and evaluated predictive parameters of right atrial spontaneous echo contrast (SEC) and thrombi. Methods: Patients with permanent AF developed due to three different etiologies (20 mitral stenosis, 44 hypertension, 20 hyperthyroidism) and 23 subjects with sinus rhythm were included into the study. RAA was examined with TEE and pulsed-wave and TDI velocities of RAA were measured. Results: Both PW-Doppler and TDI velocities were significantly impaired in all AF groups compared to controls. The lowest velocities were recorded in mitral stenosis patients. Right atrial moderate–severe SEC was observed in 75% of the mitral stenosis patients, in 25% of hypertensive patients, and in 30% of hyperthyroidism patients. Right atrial thrombus was observed in 25% of mitral stenosis, 4.5% of hypertension, and in none of the hyperthyroidism patients. In the multivariate analysis, the most important parameter associated with the severity of RAA SEC was the percent change in RAA area (B =−0.034, P = 0.03). Conclusion: In patients with permanent AF, impairment of RAA function and development of right atrial SEC-thrombus are closely related to the underlying etiology. These results suggested that evaluation of RAA functions may have an incremental value over the assessment of the LAA for determining thromboembolic risk. (Echocardiography 2010;27:384-393) Key words: right atrial appendage, permanent atrial fibrillation, transesophageal echocardiography, tissue Doppler Atrial fibrillation (AF) is the most common sustained cardiac rhythm disturbance, leading to a progressive impairment in atrial function. 1 It is often associated with structural heart dis- ease; nonetheless, a substantial proportion of pa- tients with AF have no detectable heart disease or metabolic/endocrinologic conditions like hyper- thyroidism. 1,2 Underlying heart disease plays an important role in the impairment of atrial func- tion and risk of thromboembolic events. Although many studies exist about the left atrial appendage function (LAA) in patients with AF, knowledge about the right atrial appendage (RAA) function in different AF etiologies is limited. Atrial function and thrombotic material, which arises most frequently in the appendages of atria, cannot be regularly examined by transthoracic Address for correspondence and reprint requests: Tayfun Sahin, M.D., Medical Faculty, Cardiology Department, Ko- caeli University, Umuttepe Yerleskesi Eski Istanbul Yolu 10 km 41380 Umuttepe, Kocaeli, Turkey. Fax: +90-262-3038483; E-mail: tayfunsa@yahoo.com echocardiography. 3 Transesophageal echocar- diography (TEE) is a more sensitive and specific method to assess atrial appendage function and to detect thrombus formation. TEE studies con- ducted in patients with chronic AF revealed that spontaneous echo contrast and thrombi may de- velop in RAA and one study claimed that espe- cially patients with nonvalvular AF might be at greater risk for right atrial thrombi formation. 4–6 This finding suggested that RAA function may not be equally affected in different AF etiologies. Tissue Doppler imaging (TDI) is a relatively new technique for the evaluation of atrial ap- pendage function. In a recent study, we showed that LAA functions were deteriorated in patients with AF according to different etiologies and most severely depressed in mitral stenosis and least in hyperthyroidism. 7 To the best of our knowledge, no study exists about the transesophageal TDI findings of RAA function. The aim of this study is to investigate (a) RAA transesophageal TDI ve- locities in various AF etiologies, (b) to compare the results with classical PW-Doppler findings and 384