[Paroxysmal Atrial Fibrillation after Percutaneous Thrombectomy on Day 5 of Onset of Cerebral Embolism:A Case Report].

Introduction: We report a case of embolic stroke with an atypical course after endovascular therapy performed during the subacute stage of progressive stroke, where symptom relapse could not be controlled despite medical treatment.

Case Presentation: An 81-year-old woman developed slight weakness in her left leg and was hospitalized three days after the onset of symptoms. On admission, her consciousness was almost clear and she exhibited left hemiparesis. The computed tomography(CT)and magnetic resonance imaging(MRI)revealed a cerebral infarction in the right caudate head and corona radiata, and CT perfusion showed no difference in the cerebral blood flow. However, three-dimensional computed tomography angiography showed right M1 occlusion. Considering the clinical course of the leg weakness without atrial fibrillation, antiplatelet therapy for atherosclerotic cerebral infarction was administered. Five days after the symptom onset, the left hemiparesis deteriorated. CT and diffusion-weighted MRI showed increasing edema associated with the cerebral infarction, and CTP showed decreased cerebral blood flow in the right middle cerebral artery region. Because angiography revealed an obstruction involving a long lesion with loss of contrast, we suspected an embolic stroke. Endovascular surgery was performed successfully using the Penumbra system. Postoperatively, the hemiparesis resolved and the patient was transferred to the rehabilitation hospital.

Conclusion: In rare cases, patients with an embolic stroke develop gradual progression of symptoms. To differentiate between cardioembolic stroke and atherosclerotic cerebral infarction in such patients, a follow-up examination of the brain blood flow must be performed, especially when there is a change in symptoms. This may provide useful information for intravascular treatment even in the subacute period.