Abstract
BACKGROUND: Juxtaposition of the atrial appendages is an extremely rare congenital cardiac malformation. It is usually discovered incidentally during autopsy or surgery. This report aims to increase awareness of right juxtaposition of the left atrial appendage. CASE PRESENTATION: We report a Chinese Han female aged 2 years and 10 months with recurrent lung infections after birth, who was diagnosed with congenital heart disease, corrected transposition of the great arteries, ventricular septal defect, and arterial ductus arteriosus at the local hospital and improved after the pulmonary artery banding procedure. The patient presented to our hospital with intermittent cough. During preoperative evaluation, a review of imaging data revealed a right juxtaposition of the left atrial appendage on enhanced computed tomography. CONCLUSION: Right juxtaposition of the left atrial appendage is a rare congenital heart anomaly that often occurs in conjunction with complex cardiac malformations. Diagnosis requires a combination of imaging modalities to improve detection rates. Careful identification of cardiac structures during surgery is crucial, as alterations in cardiac anatomy may increase surgical risks. For instance, the opening of juxtaposed atrial appendages could be mistaken for an atrial septal defect.