Recurrent thrombosis after carotid endarterectomy secondary to activated protein C resistance and essential thrombocytosis: A case report

A Case of Symptomatic Intraluminal Internal Carotid Artery Thrombus in a Patient with Essential Thrombocythemia Surgically Treated by CEA

We report a patient with a symptomatic intraluminal internal carotid artery thrombus clinically revealed by cerebral infarction. In the preoperative evaluation, it was revealed that essential thrombocythemia existed in the background. Therefore, medical treatment with antithrombotic agents in conjunction with hydroxycarbamide for essential thrombocythemia was initiated, but the thrombus was not dissolved by three weeks. At this time, the patient underwent carotid endarterectomy, which removed the thrombus completely with its adjacent plaque without any perioperative stroke. The possibility of essential thrombocythemia may also be kept in mind when an increased platelet count is observed in patients with internal carotid artery thrombus. It is a reasonable option to precede medical treatment, including anticoagulant therapy, by setting the time limit for surgical intervention in such a disease state.

Essential thrombocythemia with CALR mutation and recurrent stroke: two case reports and literature review

Cerebrovascular events, especially ischemic stroke, are common complications of essential thrombocythemia (ET). Compared to JAK2V617 F mutation, CALR mutation is considered as a lower risk factor of thrombosis in ET. Until now stroke in ET with CALR mutation has rarely been reported. We retrospectively investigated patients diagnosed with stroke and ET in Xijing hospital of Air Force Medical University, from 2015 to 2021. Clinical characteristics (including medical history, physical and auxiliary examination and prognosis) were recorded and associated literature was reviewed. Among the 19 patients diagnosed with both stroke and ET we retrieved, two cases were positive for CALR mutation. In case 1, a 71-year-old man developed the first ischemic event under the treatment of anagrelide, followed by a hemorrhagic stroke after receiving aspirin and clopidogrel for 4 months. Ischemic stroke reccurred and the neurological function deteriorated progressively. In case 2, a 44-year-old man presented with hypoxic-ischemic encephalopathy due to serious myocardial infarction and subsequent brain imaging indicated three times of ischemic stroke events. The patient gradually got improved through cytoreductive and antiplatelet therapy and rehabilitation. Literature review showed that cerebrovascular event is the most serious neurological complication of ET and may be the presenting symptom. Most of reported cases with ET accompanied by stroke were positive for JAK2 V617 F mutation, but with rare CALR mutation. ET with CALR mutation can cause both hemorrhagic and ischemic stroke. Identification of such rare causes of stroke is of great importance to provide precise and individualized prevention and therapy.