Drug response testing for elective carotid artery stenting: Prevalence of non-response to aspirin and clopidogrel and influence on post-interventional occurrence of cerebral ischemia.

BackgroundThe patient-associated prevalence of Clopidogrel (CPG)-and Aspirin (ASS)-nonresponse is not well understood and varies depending on the patient population. The influence of responder status for platelet inhibition in patients eligible for carotid artery stenting (CAS) on post-interventional cerebral ischemia is unknown.MethodsWe conducted a retrospective, mono-center analysis of all patients with response-test undergoing elective CAS between 2010 and 2024 and available MRI before and after CAS. Study groups were formed according to ASS- and CPG-response. Cerebral ischemia patterns were compared between study groups in univariate analysis and patient-associated co-morbidities were tested for association with drug resistance or infarction frequency.ResultsIn total, 50/68 (73.5%) of patients showed adequate response to ASS and CPG. Non-response to CPG was higher than to ASS (clopidogrel resistance rate: 14.8%, aspirin resistance rate: 9.2%). All patients with non-response were bridged with GP IIb/IIIa antagonist tirofiban during CAS. Under these conditions, the responder status did not influence post-interventional cerebral infarction patterns.ConclusionAntiplatelet non-response, especially for CPG, is very frequent in patients undergoing CAS. When bridging patients with tirofiban during intervention, responder status had no influence on post-interventional cerebral infarction patterns.