[Juxtaposition of the atria]

Area of Science:

• Cardiology
• Developmental Biology
• Pediatric Medicine

Context:

• Congenital heart defects (CHDs) represent a significant challenge in pediatric cardiology.
• Atrial appendage anomalies, particularly left juxtaposition, are infrequently encountered but associated with complex cardiac malformations.
• Understanding the embryological origins and clinical implications of these anomalies is crucial for diagnosis and management.

Purpose:

• To investigate the morphological features and associated cardiac defects in cases of right atrial appendage juxtaposition.
• To explore potential embryological explanations for the development of juxtaposed atrial appendages.
• To highlight the clinical significance of this anomaly as an indicator of severe cyanotic congenital heart disease.

Summary:

• This study examined six cases of right atrial appendage (RAA) juxtaposition, an anomaly where the RAA arises from the anterior wall, adjacent to the atrial septum, and is positioned left of the great arteries.
• Associated complex congenital heart defects included single outlet, right ventricular hypoplasia, absent atrioventricular connection, septal defects, and pulmonary outflow obstruction.
• Other observed malformations were anatomically corrected malposition of the great arteries, bilateral infundibulum, and right aortic arch.

Impact:

• The presence of juxtaposed atrial appendages, while not a syndrome itself, is a critical indicator of severe cyanotic congenital heart disease, necessitating heightened clinical and surgical awareness.
• This finding aids in understanding the spectrum of congenital heart anomalies and their embryological underpinnings.
• The study contributes to the knowledge base for diagnosing and managing rare cardiac malformations in neonates and infants.