1 ︱ INTRODUCTION
With the improvement of echocardiography, cardiac catheterization, and device materials, transcatheter closure of atrial septal defect (ASD) has gradually replaced traditional thoracotomy surgery as the optimal treatment for patients with indications. However, long-term complications of catheter-based closure, especially device-related malposition, embolization, and thrombus formation, seriously threaten the life and health of patients 1. Bi-atrial thrombus formation-induced cerebral infarction and pulmonary embolism are rare but life-threatening late complications. Left atrial thrombus dislodges to the arteries of the brain, mesentery, and extremities, which can cause stroke, intestinal necrosis, and extremity ischemia; meanwhile, right atrial thrombus dislodges to the pulmonary artery and causes pulmonary embolism. Both conditions are common causes of acute cardiac arrest and sudden death.