Case Report: Recurrent Intra-operative thrombosis in a patient undergoing carotid endarterectomy: possible sticky platelet syndrome?

Introduction: Sticky platelet syndrome (SPS) is an inherited autosomal dominant platelet disorder associated with arterial thrombosis. First described by Dr. Mammen in 1984, SPS leads to hyperaggregability of platelets in response to physiologic stimuli, often ADP and/or epinephrine. In this report, we describe a case of a patient undergoing carotid endarterectomy with multiple recurrent episodes of intraoperative thromboses and clot formation despite aggressive anticoagulation that resolved only with administration of antiplatelet aggregating agent.
Abstract/Methods: We report a case of a 77 year old male who underwent an elective left-sided carotid endarterectomy for asymptomatic internal carotid artery stenosis. Endarterectomy with patch angioplasty was performed under general anesthesia with evaluation of stump pressures and elective shunting. Intraoperative completion carotid duplex scan revealed formation of a thrombus at the distal native ICA that on examination revealed a white clot worrisome for heparin-induced thrombocytopenia. Despite removal of heparin and administration of dextran and direct thrombin inhibitors including argatroban and refludan, the patient continued to form clot. Patch revision and eventually excision with vein replacement failed to identify any anatomic or mechanical defects. Clot formation was eventually halted with administration of the GIIb/IIIa inhibitor, Reopro. Postoperatively, the patient remained without significant neurologic sequelae. Hematologic evaluation revealed no hypercoagulable predisposition. The patient has been maintained on aspirin and plavix with no appreciable re-stenosis on follow-up imaging.
onclusion: Sticky platelet syndrome (SPS) may be an underrecognized cause of thromboembolic complications in carotid endarterectomy patients who often sustain not only endothelial injury.