Alternative anticoagulants in heparin-sensitive patients undergoing carotid artery interventions: A scoping review

BACKGROUND: Systemic unfractionated heparin (UFH) is routinely administered as procedural anticoagulation during carotid artery procedures. However, types I, II, and IV hypersensitivity to heparin can occur amongst patients with carotid artery disease who require carotid endarterectomy (CEA) or carotid artery stenting (CAS). Although rapid-acting nonheparin alternatives are available, their use for procedural anticoagulation in patients with suspected heparin hypersensitivity undergoing carotid intervention has not been thoroughly studied. We sought to evaluate the safety of nonheparin anticoagulant use in carotid artery interventions. METHODS: A PRISMA-structured scoping review was done to evaluate the outcomes of carotid interventions performed with nonheparin intraoperative anticoagulation. To do so, primary literature published between 1993 and 2025 was obtained using structured searches of PubMed, OVID Medline, and OVID Embase. Studies were included if they assessed major adverse cardiovascular events and excessive bleeding associated with nonheparin anticoagulation in CEA and CAS and were excluded if they did not have a primary focus on surgical outcomes or were not original research. Data on study characteristics, patient population, intervention, and clinical outcomes were extracted and summarized using a narrative synthesis to identify trends in the incidence and type of complication for a given alternative anticoagulant relative to UFH. RESULTS: A total of 90 deduplicated citations were identified, of which 21 met the criteria for inclusion. Eleven studies evaluated bivalirudin, six evaluated argatroban, and four evaluated low-molecular-weight heparin (LMWH). The bivalirudin literature included three case reports describing its use in CEA, as well as two randomized controlled trials and six retrospective cohort studies on its use in CAS. Bivalirudin was found to be safe for carotid procedures and was associated with less bleeding compared with UFH. Argatroban use was described in five case reports of CEA and one of CAS, none of which reported adverse events. Finally, two prospective randomized controlled trials, a retrospective cohort study, and a case series compared different LMWHs with UFH in CEA and found no significant difference in thrombotic or hemorrhagic events between the two treatment groups, but did note a lower risk of embolism with LMWH. CONCLUSIONS: In patients with suspected UFH hypersensitivity requiring carotid intervention, bivalirudin appears to be a safe alternative, while argatroban and LMWH may represent acceptable options based on limited available evidence. Bivalirudin, in particular, is associated with less perioperative bleeding and no increase in periprocedural complications.