Relationship between the blood flow patterns of left atrial appendage(LAA) with spontaneous contrast(SC) echogenecity and thrombi in LAA

Huh, Seoung Ho; Kim, Kee Sik; Song, Young Sung; Kim, Yoon Nyun; Kim, Kwon Bae

Abstract

BACKGROUND
Patients with sinus rhythm, the left atrial appendage(LAA) appeared as a vigorously contracting structure and the blood flow patterns of LAA showed biphasic configuration. However, patients with AF rhythm the blood flow showed irregular or no configuration in doppler echocardiographic study. The purpose of this study is to evaluate relationship between the blood flow patterns of LAA with the presence of spontaneous contrast(SC) and thrombi in LAA. METHODS: We performed TEE and TTE simultaneously to 58 consecutive patients who had native mitral valve disease or mitral prosthesis. Spontaneous contrast(SC) and the presence and location of LAA thrombi were evaluated during TEE and left atrial dimension(LAD) & ejection fraction(EF) were evaluated during TTE. We divided the whole subjects into three groups according to the blood flow patterns ; regular pattern(Group 1), irregular pattern(Group 2), no flow pattern(Group 3). RESULTS: 1) Blood flow within the left atrial appendage is divided with three groups among of them, atrial fibrillation have two blood flow patterns. 2) Peak prositive & negative flow velocity within LAA in AF rhythm groups were slower than normal sinus rhythm group.(p<0.01) 3) Left atrial dimension in group 3 is significantly larger than others groups.(p<0.01) 4) Spontaneous contrast(SC) with LAA could be detected in 2(6.8%) of the 29 patients of group 1, 6(31.5%) of the 19 patients of group 2, 10(100%) of the 10 patients of group 3. Incidence of SC within LAA in group 3 is significantly higher than others groups. 5) LAA thrombi could be detected in 1(3.4%) of the 29 patients of group 1, 1(5.2%) of the 19 patients of group 2, 3(30%) of the 10 patients of group 3. Incidence of LAA thrombi is significangly higher than other groups. CONCLUSIONS: We can suggest that blood flow within LAA is divided into three groups according to the blood flow patterns, and spontaneous contrast and thrombi in LAA were closely related with the blood flow pattern.