Spontaneous echo contrast is an echogenic swirling pattern of blood flow, distinct from white noise artifacts, caused by an increased ultrasonic back-scatter from aggregation of the cellular components of blood in the conditions of blood stasis or low-velocity blood flow. 1,2 Although this phenomenon frequently develops in a dilated and dysfunctional left atrium and left atrial appendage during atrial fibrillation, it can develop in any cardiac chamber during any rhythm if the blood flow velocity is markedly low. 3,4 The presence of spontaneous echo contrast in the left atrium and left atrial appendage has been associated with a higher risk of thromboembolism and cerebrovascular accident. 5,6
A transesophageal echocardiogram was performed to evaluate a mitral valve prosthesis in a 51-year-old man. The patient was taking warfarin, and the international normalized ratio (INR) was 3.4 when we performed transesophageal echocardiography. The patient was in sinus rhythm. The transesophageal echocardiographic examination revealed a dilated left atrium and left atrial appendage. The left atrial appendage was multilobulated and contained homogenous finger-like pectinate muscles and spontaneous echo contrast (Figs. 1 and 2). No thrombi were seen in the left atrium or in the left atrial appendage. The contractile function of the left atrial appendage was markedly decreased, with a peak left atrial appendage systolic velocity of 15 cm/sec (normal, ≥40 cm/sec) on Doppler evaluation.
Fig. 1 Mid-esophageal echocardiographic view of the left atrium and left atrial appendage in a 123° plane shows spontaneous echo contrast.
Real-time motion image is available at www.texasheartinstitute.org/siddiqui284.html.
Fig. 2 Diagram illustrates various components of Figure 1.
1 = left atrium; 2 = left atrial appendage; 3 = pectinate muscles; 4 = lobules of left atrial appendage; 5 = spontaneous echo contrast; 6 = pulmonary trunk
Supplementary Material
Footnotes
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Address for reprints: Ijaz A. Khan, MD, Creighton University Cardiac Center, 3006 Webster Street, Omaha, NE 68131-2044
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