Thrombus attached to a Sideris septal occluder device after 6 years

History and clinical findings: A 61-year-old man was admitted to hospital because of right-sided hypaesthesia. Additionally he reported a brief speech disturbance some weeks before. Neurological examination indicated right-sided sensomotoric hemiparesis and left-sided upper quadrant anopia. 6 years ago recurrent transient ischaemic attacks (TIA) was diagnosed caused by paradoxical embolism through a persistent foramen ovale (PFO). The PFO was closed with a 45mm Sideris button occluder device. After this, he reported no symptoms of cerebral ischaemia and he did not take any antiplatelet therapy. Investigations: Transesophageal echocardiography (TEE) showed a left atrial thrombus attached to the occluder. Cerebral computed tomography revealed infarction in regions supplied by the right posterior cerebral artery and left media cerebral artery. As additional risk factor for thrombosis a heterocygous factor V Leiden mutation was diagnosed. Diagnosis: Multiple cerebral infarctions caused by a thrombus attached to an occluder system 6 years after interventional closure of persistent foramen ovale in a patient with heterocygous factor V Leiden mutation. Treatment and course: The patient was anticoagulated (phenprocournon) and the thrombus gradually dissolved. Conclusion: A thrombosis on a Sideris occluder device may cause cerebral infarctions even years after transcatheter closure of a PFO.