Triatrial Appearance in a Patient With Atrial Septal Defect: A Case Report

Area of Science:

• Cardiology
• Congenital Heart Disease
• Medical Imaging

Background:

• Atrial septal defect (ASD) is a common congenital heart anomaly.
• Complex anatomical variations can mimic a triatrial heart, complicating diagnosis.
• Accurate differentiation is vital for appropriate clinical management.

Observation:

• A 25-year-old male presented with exertional dyspnea and fatigue.
• Initial transthoracic echocardiography suggested ostium secundum ASD with a right atrial membrane, raising suspicion for cor triatriatum dexter (CTD).
• Further evaluation with transesophageal echocardiography and cardiac CT revealed an incomplete CTD (iCTD).

Findings:

• Multimodality imaging successfully differentiated incomplete CTD from true triatrial division in an ASD patient.
• Cardiac catheterization confirmed an operable left-to-right shunt and mild pulmonary arterial hypertension.
• The patient underwent successful surgical closure of the ASD and membrane excision.

Implications:

• This case underscores the necessity of advanced imaging techniques for precise anatomical assessment in complex ASD cases.
• Misdiagnosis of iCTD can lead to suboptimal management strategies.
• Utilizing 3D TEE and cardiac CT is essential for accurate diagnosis, surgical planning, and improved patient outcomes.