Journal of Ultrasound in Medicine, Vol 9, Issue 3 151-155, Copyright © 1990 by American Institute of Ultrasound in Medicine
Contributing factors to formation of left atrial spontaneous echo contrast in mitral valvular disease
Y. T. Chen, M. N. Kan, J. S. Chen, W. W. Lin, D. S. Hwang, M. Chang, D. Y. Lee, S. L. Hwang and B. N. Chiang
Division of Cardiology, Taichung Veterans General Hospital, Taiwan, Republic of China.
The formation of left atrial spontaneous echo contrast may relate to blood
stasis. This study analyzed the factors contributing to the formation of
that contrast. Transesophageal echocardiography, transthoracic
echocardiography, cardiac catheterization, and left ventricular angiography
were performed in 139 patients, divided into five groups. Predominant
mitral stenosis with atrial fibrillation was found in 36 patients (group
I); normal porcine valve in the mitral valvular area with atrial
fibrillation in 31 (group II); predominant mitral stenosis with normal
sinus rhythm in 26 (group III); moderate to severe mitral regurgitation
with atrial fibrillation in 25 (group IV); atrial fibrillation with normal
mitral valve in 21 (group V). The results showed left atrial spontaneous
contrast echo was found in only 1 of 139 patients by transthoracic
echocardiography and 62 of 139 cases were detected by transesophageal
echocardiography. There was a high incidence of left atrial spontaneous
echo contrast in cases of mitral obstruction with atrial fibrillation and
enlarged left atrium (group I, 88%; group II, 74%), but a lower incidence
in cases with normal sinus rhythm (group III, 4%), atrial fibrillation
alone (group V, 16%), and increased left atrial flow velocity (group IV,
9.5%). The diameter of the left atrium was significantly different between
presence and absence of left atrial spontaneous contrast echo (54.3 +/- 9.2
mm vs. 48.3 +/- 8.6 mm, p less than 0.01). The mean pressure gradient was
similar in groups I and III (14.6 +/- 0.6 mHg and 14.4 +/- 2.8 mHg,
respectively) but different in group II (10.9 +/- 3.2 mHg, p less than
0.05).(ABSTRACT TRUNCATED AT 250 WORDS)