To examine practice variations in anti-thrombotic management of patients with “hot carotids” awaiting carotid endarterectomy(CEA) or angioplasty/stenting(CAS)

Patients with acutely symptomatic carotid stenosis(“hot carotid”) have high up-front risk of recurrent strokes. Uncertainties remain regarding optimal anti-thrombotic management, particularly while awaiting revascularisation with CEA/CAS. Systematically examining equipoise could inform future trials.

We administered a worldwide electronic survey through Neurology: Clinical Practice containing three representative cases with symptomatic 80% extracranial internal carotid artery stenosis. Respondents(n=668,71 countries) chose their preferred revascularization procedure, typical CAS/CEA wait-time, and favoured anti-thrombotic regimen. We also interviewed 20 stroke physicians regarding their approach to “hot carotid” anti-thrombotic management. We used snowball sampling, continuing until we interviewed neurologists, neurosurgeons, internists/geriatricians, and interventional neuroradiologists from ≥3 continents and achieved thematic saturation.

The majority of respondents favoured CEA(69.1%), an aspirin-containing regimen(88.5%), and a clopidogrel-containing regimen(64.4%) if already on aspirin. Monotherapy was favoured by 54.4-70.6% across scenarios. The preferred dual-therapy was low-dose aspirin(75-100mg) plus clopidogrel(22.2%), or high-dose aspirin(160-325mg) plus clopidogrel if already on aspirin(12.2%). Respondents favouring CAS more often chose ≥2 agents(aOR vs CEA:2.00,95%CI 1.36-2.95,p=0.001) or clopidogrel-containing regimens(aOR:1.77,1.16-2.70,p=0.008). Regional differences included European respondents choosing multiple agents less commonly if already on aspirin(aOR vs USA/Canada:0.57,0.35-0.93,p=0.023) whereas Asian respondents did so more often(aOR:1.95,1.11-3.43,p=0.020). Factors increasing enthusiasm for ≥2 anti-thrombotics included: multiple TIAs(57.2%), intra-luminal thrombus(58.5%), and ulcerated plaque(57.4%); 56.3% identified MRI microbleeds as decreasing enthusiasm. The qualitative interviews demonstrated that surgeons’ concerns about beeding often resulted in patients being on single anti-platelet peri-operatively, especially in USA/Canada, whereas neuroradiologists favoured performing CAS on dual therapy.

Our results highlight the heterogenous anti-thrombotic management of “hot carotids”. Future trials should likely include high-dose aspirin monotherapy or low-dose aspirin/clopidogrel dual-therapy as a comparator arm to stimulate enrolment. Given differences in equipoise between surgeons and neuroradiologists, such a trial would ideally involve one procedure(e.g.CEA) rather than a mix of CEA/CAS.