Fatal disseminated paradoxical embolism in inferior sinus venosus atrial septal defect

Inferior sinus venosus arterial septal defect (ASD) is a rare congenital cardiac anomaly. As with other types of ASDs and patent foramen ovale (PFO), this results in arteri-venous shunting the risk developing paradoxical embolism (PDE) to systemic circulation from venous emboli. We report case 67-year-old lady presented emergency department (ED) massive pulmonary (PE) recurrent acute limb ischaemia. On CT angiography (CTPA), an incidental finding inferior ASD was discovered that has caused PDE. Thrombolysis administered followed by open mechanical thrombectomy. The patient developed lower gastrointestinal bleed post thrombolysis then passed away despite embolization. This describes catastrophic effect PDE cause disseminated multisystem thromboembolism. It also emphasizes importance early detection possible right-to-left shunt patients Transthoracic echocardiography reduced sensitivity for requiring further assessment transoesophageal selected cases.