Clinical implications of left atrial spontaneous echo contrast in mitral valve disease.

The aim of this study was to investigate the factors related to the presence of left atrial spontaneous echo contrast in mitral valve disease, and to ascertain whether it is a predictor of thromboembolism. One hundred and one patients (47 men, 54 women) with a mean age of 57.04 +/- 10.6 years who underwent transthoracic and transesophageal echocardiography were included in the study. Forty-five (44.5%) had isolated or predominant mitral valve stenosis, 12 (11.9%) predominant mitral insufficiency and 44 (43.6%) had had previous mitral valve replacement. Left atrial spontaneous echo contrast was detected by transesophageal echocardiography in 58 patients, while the transthoracic approach detected it in only 15 (14.9%) (P < 0.0001). An atrial thrombus was found in six cases, with a history of recent systemic embolism in three of them. There was no thrombus in the left atria of a further nine patients, despite definitive histories of recent systemic embolism. The finding of left atrial spontaneous echo contrast was related to the presence of atrial fibrillation or enlarged left atrium, the severity of mitral stenosis and the absence of significant mitral insufficiency. Anticoagulant therapy was not significantly associated with spontaneous left atrial echo contrast, but a stepwise linear regression analysis showed that its presence was the only independent predictor of thromboembolism (p < 0.0001). We conclude that left atrial spontaneous echo contrast in mitral valve disease can be discovered mainly by transesophageal echocardiography, and is correlated with factors which are associated with low left atrial blood flow velocity such as atrial fibrillation, enlarged left atrium, mitral stenosis of increased severity and the absence of significant mitral insufficiency.(ABSTRACT TRUNCATED AT 250 WORDS)