Is Left Atrial Spontaneous Echo Contrast Transforming to Thrombus in Patients Who Have Rheumatic Mitral Disease? A Prospective Study

We aimed to investigate in a prospective manner the association of left atrial spontaneous echo contrast and thrombus determined in many cross-sectional and retrospective studies. Of the 113 cases with rheumatic mitral and/or aortic valve disease, 42 cases in whom spontaneous echo contrast was detected were included in the study after a clinical (electrocardiography, history, physical examination) and laboratory assessment for inclusion and exclusion criteria. Patients were randomly divided into two groups of 21 patients each, one placed on anticoagulants and the other serving as control group. Patients were clinically followed-up regularly at certain periods, and re-assessed 6 months later for spontaneous echo contrast and thrombus using transesophageal echocardiography. Thirty patients completed the study. The two study groups were not different from each other in terms of the parameters studied. Thrombus developed in 9 patients (30 %) at the end of the follow-up period. There was a significant difference between the thrombus and non-thrombus groups in terms of the use of anticoagulants, the presence of mitral regurgitation and density of spontaneous echo contrast (p<0.05). Logistic regression analysis showed that the only independent predictor of left atrial thrombus formation was spontaneous echo contrast (p<0.05, r=0.351). The relative risk of the absence of mitral regurgitation and dense spontaneous echo contrast for development of thrombus were 3.4 and 5.5, respectively, in comparison with 1.65-folds increase caused by the use of anticoagulant (p<0.05). In conclusion, thrombus may develop in cases with rheumatic mitral stenosis, in the presence of left atrial spontaneous echo contrast, particularly in the absence of mitral regurgitation, while the use of anticoagulants has a preventive effect on this process.