Abstract 134: Recognizing Tirofiban Induced Thrombocytopenia After Acute Carotid Stenting in Mechanical Thrombectomy: A Case Report

• Published in: Stroke: vascular and interventional neurology Vol. 4; no. S1
• Main Authors: Alqudah, A, Antzoulatos, A, Haussen, D, Dolia, J
• Format: Journal Article
• Language: English
• Published: Phoenix Wiley Subscription Services, Inc 01-11-2024
• Subjects: Blood clots; Blood platelets; Case reports; Ostomy; Thrombocytopenia
• ISSN: 2694-5746; 2694-5746
• DOI: 10.1161/SVIN.04.suppl_1.134

IntroductionTirofiban, a glycoprotein IIb/IIIa receptor blocker, is commonly used in mechanical thrombectomy (MT) as an effective IV antiplatelet. A rare but significant side effect is severe thrombocytopenia, reported in 0.1%‐0.5% of clinical trials1. This reaction is thought to be caused by drug‐dependent antibodies binding to GP IIb/IIIa following conformational changes. While acute stenting for carotid stenosis is well established, data on this side effect remains limited2. We present a case of severe thrombocytopenia following second exposure to tirofiban in a patient undergoing mechanical thrombectomy and internal carotid artery stenting.MethodsCase report of severe thrombocytopenia associated with tirofiban use in acute carotid stenting.Case PresentationA 60‐year‐old Caucasian male with a history of hypertension and peripheral artery disease (PAD) presented with acute onset of right‐sided hemiplegia and aphasia, NIHSS 12, concerning for left middle cerebral artery (MCA) syndrome. CT angiography showed an occlusive thrombus in the left ICA and LM2. Thrombolytic therapy wasn't given due to an unknown last known well time. Initial management included mechanical thrombectomy (MT) for left M2 occlusion, achieving TICI3 reperfusion. Severe stenosis of the left ICA reoccluded but was successfully recanalized, followed by stenting. The patient was loaded with aspirin 300 mg and tirofiban 12.5 mcg/kg (total 1000 mcg). Tirofiban infusion at 0.08 mcg/kg/min for 80 kg (rate: 7.68 ml/hr) was discontinued after 25 hours.Nine hours post‐procedure, the patient became unresponsive, concerning for reocclusion. Angiogram showed a sub‐occlusive, non‐flow‐limiting thrombus in the ICA stent. The patient was transitioned to dual‐antiplatelet therapy (DAPT) with aspirin and ticagrelor. On day 4, 96 hours post‐infusion, the platelet count dropped from 216 times10⁹ on admission to 110 times10⁹, with a negative HIT panel. The patient stayed on DAPT until day 12, with platelet count at 133 times10⁹. Ticagrelor was held, and tirofiban was restarted for percutaneous endoscopic gastrostomy (PEG) tube placement. The second tirofiban infusion at 0.08 mcg/kg/min (rate: 7.06 ml/hr) lasted 29 hours, after which the platelet count dropped to 38times10⁹. Tirofiban discontinued, and the patient was maintained on ASA 81 mg. Platelet count improved, reaching 245 times10⁹ after 4 days.ConclusionThis case demonstrates a rare adverse effect of Tirofiban, severe thrombocytopenia after second exposure. While the mechanism is unclear, it is likely related to immune‐mediated thrombocytopenia from drug‐dependent antibodies (DDAbs)3. This highlights the importance of monitoring platelet count in patients on tirofiban and suggests that re‐exposure and the interval between exposures may increase the risk of this rare effect.