Left Atrial Appendage Outpouching Mimicking Coronary Artery Aneurysm on Pediatric Echocardiography.

IMAGE(S): Multimodality imaging of a tubular left atrial appendage outpouching mimicking coronary artery aneurysm on pediatric echocardiography.

CASE SUMMARY: A 3-year-old child with a recent history of febrile illness of unclear etiology underwent transthoracic echocardiography during evaluation of a heart murmur. A tubular outpouching adjacent to the proximal left coronary artery raised concern for possible coronary artery involvement, including coronary artery aneurysm. Doppler findings were nondiagnostic. Cardiac computed tomography demonstrated a narrow connection between the structure and the left atrial appendage. The findings were consistent with a tubular left atrial appendage outpouching without anatomical continuity with the coronary arteries. Three-dimensional reconstruction clarified the projection-dependent overlap responsible for the false echocardiographic appearance.

TAKE-HOME MESSAGES: Anatomical overlap between a tubular left atrial appendage outpouching and proximal coronary arteries may mimic coronary artery aneurysm on pediatric echocardiography. Careful multiplanar assessment and multimodality imaging can clarify the true anatomical relationship when echocardiographic findings remain inconclusive.