Lysis of a thrombus in the internal carotid artery by a glycoprotein IIb/IIIa receptor antagonist

History: A 55-year-old man was admitted with acute right-sided arm and leg paralysis and motor aphasia, which were regressing at time of admission. He was known to have had several episodes of abnormal motor function in the right arm resulting from transitory cerebral ischaemic attacks. He was a heavy smoker. Investigations: Cranial computed tomography (CCT) excluded acute bleeding and there was no evidence of a stroke. Duplex sonography showed a filiform stenosis at the origin of the left internal carotid artery (ICA) with an echo-poor structure in the distal lumen. Subsequent angiography demonstrated an inoperable thrombus adherent to the filiform left ICA stenosis and extending to the base of the skull. Diagnosis, treatment and course: The neurological symptoms regressed over 24 hours, confirming the diagnosis of prolonged ischaemic neurological deficit. CCT having excluded bleeding, but significant left ICA stenosis by a thrombus having been demonstrated, treatment with acetyl salicylic acid (aspirin) and heparin was initiated. After the described angiographic confirmation of a thrombus adherent to the filiform stenosis, treatment with Tirofiban, a glycoprotein (GP) IIb/IIIa receptor antagonist, was begun and the thrombus completely dissolved. The filiform ICA stenosis was then treated surgically. Conclusion: This case demonstrates complete lysis of a long thrombus in the ICA by Tirofiban, making a primarily inoperable stenosis amenable to surgical intervention. It is not yet clear whether administration of CP IIa/IIIb receptor antagonists provides a therapeutic option in the treatment of intracranial arterial thromboses.