Evaluation of aspirin resistance and the presence of unstable carotid plaque in patients undergoing carotid endarterectomy

Abstract

1. Prevalence of increased platelet reactivity despite ASA treatment (ASA resistance) in patients treated surgically for carotid artery disease is high, suggesting a possibility of ineffective antiplatelet therapy. 2. A modest correlation between abnormal platelet response during treatment with ASA and the presence of unstable plaques suggests that these two phenomena may coexist but we were unable to show a clear association between them.

Association of thrombelastographic parameters with post-stenting ischemic events

“…However, some patients show resistance to clopidogrel or aspirin and impaired inhibition of platelet aggregation 12. It has been estimated that 4.2–31.0% of patients treated with clopidogrel do not achieve an appropriate level of efficacy of platelet activity,13–15 and aspirin resistance accounts for 7.8–32.0% of patients with recurrent events 16 17. Many platelet function tests have been used to define the responsiveness of patients with cardiovascular disease to clopidogrel or aspirin 16.…”

Review of aspirin and clopidogrel resistance in peripheral arterial disease

“…37 In addition, a study of 66 patients taking 75 mg of aspirin monotherapy in the preoperative and perioperative period found that there was a possible correlation (P ¼ .051) between AR (32% of patients) and the presence of unstable carotid artery plaques at carotid endarterectomy. 36 Several studies have identified a transient AR in the perioperative period. A study of platelet response to AA in patients taking aspirin immediately before and immediately after carotid endarterectomy revealed a 570% increase in platelet aggregation to AA after the procedure compared with the low AA response before surgery, with no additional intake of aspirin.…”

The Pre- and Postoperative Prevalence and Risk Factors of ASA Nonresponse in Vascular Surgery

“…Temporary postoperative ASA nonresponse is clinically relevant since it may influence the rate of thromboembolic complications. [19][20][21] Lewszuk et al 21 investigated 66 patients who underwent a carotid endarterectomy and were pre-treated with ASA 75 mg/d. They measured platelet aggregation with the analyzer PFA-100 on the second day after the operation and identified a nonresponder rate of 32% (19 out of 66 patients).…”

“…Lewszuk et al 21 investigated 66 patients who underwent a carotid endarterectomy and were pre-treated with ASA 75 mg/d. They measured platelet aggregation with the analyzer PFA-100 on the second day after the operation and identified a nonresponder rate of 32% (19 out of 66 patients).…”