Siblings with Idiopathic Left Atrial Appendage Ostial Stenosis and Cor Triatriatum

Area of Science:

• Cardiology
• Pediatric Cardiology
• Medical Imaging

Background:

• Isolated left atrial appendage (LAA) ostial stenosis is an exceedingly rare condition typically identified incidentally in adults.
• Cor triatriatum, a congenital heart anomaly, shares some diagnostic considerations with LAA ostial stenosis.

Observation:

• A 3-month-old infant presented with suspected cor triatriatum, prompted by a sibling's history of surgical treatment for the condition.
• Echocardiography initially suggested cor triatriatum, leading to further investigation.

Findings:

• Cardiac catheterization confirmed an isolated narrowing of the left atrial appendage (LAA) ostium, establishing the diagnosis of LAA ostial stenosis.
• This represents the first documented pediatric case of idiopathic LAA ostial stenosis.

Implications:

• Highlights the importance of considering LAA ostial stenosis in pediatric differential diagnoses, particularly when cor triatriatum is suspected.
• The case underscores the need to differentiate between LAA ostial stenosis and cor triatriatum, aiding in understanding their distinct etiopathogenesis.