A rare case of non-obstructed total anomalous pulmonary venous connection with a giant superior vena cava aneurysm complicated by acute young ischemic stroke.

BACKGROUND: Non-obstructed total anomalous pulmonary venous connection (TAPVC) with a giant superior vena cava aneurysm (SVCA) is rare. This combination in a young patient presenting with acute ischemic stroke has not been previously reported. CASE PRESENTATION: We report a 32-year-old male who presented with acute ischemic stroke. He also had TAPVC, SVCA and atrial septal defect with a bidirectional shunt (primarily right to left), which may represent a potential mechanism for the index stroke. And we discussed the possible mechanisms in detail. CONCLUSIONS: This case underscores the need for comprehensive imaging and consideration of rare congenital heart defects in young stroke patients. Multimodal imaging is crucial for diagnosis and treatment planning. The combination of TAPVC with nonobstructive SVCA is extremely rare, and this case provides valuable insights into its presentation and management. TRIAL REGISTRATION: Qinhuangdao S&T Plan Program (No. 202401A076).