Intraoperative Transesophageal Echocardiographic Detection of Interatrial Septal Band in Ostium Secundum Atrial Septal Defect with Deficient Rims: A Clinical Image.

Ostium secundum atrial septal defect (ASD) is the most common form of interatrial shunt, and its management depends on defect size, shunt direction, and adequacy of surrounding rims. Device closure is not feasible when inferior vena cava (IVC) or posterior rims are deficient, and such cases require surgical repair. We describe a 19-year-old female with a 28 mm ostium secundum ASD, deficient IVC and posterior rims, and right heart chamber dilation who was scheduled for minimally invasive surgical closure. Intraoperative transesophageal echocardiography (TEE) revealed a linear band within the left atrium adjacent to the deficient septum. Surgical inspection confirmed an interatrial band traversing the defect from the coronary sinus to the superior vena cava. Partial excision of the band was carried out along with ASD repair. The postoperative recovery was uneventful, with no arrhythmias or conduction disturbances, and the patient was discharged in stable condition. This case underscores the value of intraoperative TEE in delineating both expected anatomy and rare anomalies such as interatrial septal bands, which may influence surgical planning and outcomes.