Hypoxemia After Inferior Atrial Septal Defect Repair Due to Iatrogenic Diversion of Inferior Vena Cava to Left Atrium: A Case Report

Abstract

Iatrogenic diversion of the inferior vena cava (IVC) into the left atrium (LA) is a rare but serious complication of surgical atrial septal defect (ASD) repair, particularly in inferior or low-lying defects. When echocardiography is inconclusive, cross-sectional imaging can be critical for diagnosis.

A 17-year-old girl with a history of surgical closure of a low-lying ASD at 15 years of age presented with exertional dyspnea and mild oxygen desaturation of 90%-94%. Transthoracic echocardiography showed an intact atrial septal patch. Still, it could not clearly demonstrate the relationship of the inferior vena cava to the right atrium or assess the inferior margin of the repair. Contrast-enhanced CT angiography demonstrated direct drainage of the IVC into the LA with exclusion of the IVC orifice from the right atrium by the atrial septal patch, confirming iatrogenic diversion of the IVC. The patient was referred for surgical re-exploration and corrective re-repair. However, the details of the revision surgery are not available. 

Iatrogenic diversion of the IVC should be suspected in postoperative ASD patients presenting with unexplained desaturation when echocardiography is inconclusive. CT angiography provides definitive delineation of caval drainage and patch anatomy, enabling accurate diagnosis. This case also underscores the importance of careful intraoperative identification of the inferior rim and confirmation of IVC drainage during repair of low-lying ASDs to prevent this complication.