Adult Echocardiography Practice Exam

Which of the following is not a source of confusion in diagnosing left ventricular thrombus?

1. Prominent apical trabeculations

2. False tendon

3. Moderator band

4. Abnormally located papillary muscle

The correct answer is: Moderator band

The correct answer indicates that the moderator band is not a source of confusion in diagnosing left ventricular thrombus. The moderator band is a muscular structure that extends from the interventricular septum to the wall of the left ventricle and is usually not mistaken for a thrombus. Its position and structure are well understood in the context of echocardiographic imaging, which allows for clear differentiation from any thrombus that might form in the left ventricle. In contrast, prominent apical trabeculations, false tendons, and abnormally located papillary muscles can closely resemble or mimic the echogenicity and imaging characteristics of a left ventricular thrombus. Prominent apical trabeculations, for instance, can have high echogenicity and irregular shapes that may confuse the interpretation. False tendons can appear as linear structures within the left ventricle and can be misidentified as thrombus. Abnormally located papillary muscles can also create a diagnostic challenge because they might occupy areas where a thrombus might typically be encountered, leading to potential misinterpretation. Understanding these anatomical variations and their echogenic appearances is crucial for avoiding misdiagnosis. The moderator band, however, typically does not present such diagnostic difficulties, making it the clear choice