Abstract
Platelet activation in cerebrovascular diseases is associated with recurrent stroke and death. Aspirin is an effective antiplatelet agent, exhibiting its action by irreversibly inhibiting platelet cyclooxygenase-1 enzyme, thus preventing the production of thromboxane A2 (TXA2). Objectives: The study is designed to find the frequency of aspirin resistance (AR) among acute ischemic non-cardioembolic stroke patients, and to assess the clinical picture of those patients. Mehtods: This study included 80 patients39 males and 41 females (mean age: 63 years 11.8 SD), they were diagnosed clinically and via brain imaging within 24 hours following stroke onset. They were given non coated, same preparation of aspirin 150 mg/day regularly and under observation, Low molecular weight heparin 40 mg per day. The patients were followed up clinically and via GCS, NIHSS and APACHEII scales. Assessment of aspirin resistance was done one week after regular aspirin intake through: bleeding time, coagulation time and assessment of thromboxaneA2 level in serum using ELIZA. The patients were classified into two groups aspirin resistant (AR) and aspirin sensitive (AS) and the data were compared in both. Results: AR patients represented 33.75% of our sample. History of TIAs and stroke was more prevalent among them. In AR patients: the followings were also more frequent: more affection of consciousness, power, sensation, language, coordination, vertigo, vomiting, large size of cerebral infarcts, temporal and parietal infarcts. There were high significant negative correlation between GCS and TXA2level and between the later and changes in bleeding time in the first day and 7 days following stroke onset. On the other hand there were high positive correlation between TXA2 level and NIHSS score and infarct size. Coclusion: AR was frequent among ischemic non-cardioembolic stroke and they were associated with history of TIAs and previous strokes, and presented with more severe clinical presentation and larger size of cerebral infarcts, So early identification of AR prevents its fruitless use.
Highlights
Arterioarterial microthromboembolism is an important factor in the pathogenesis of ischemic stroke
Aspirin resistance was found to be present in 27 patients (33.75%) out of the 80 surviving ischemic stroke patients during the week of the study
Regarding other risk factors of stroke as smoking, diabetes, hypertension, dyslipideamia, migraine, obesity, obstructive sleep apnea and contraceptive pills, there was no significant difference between the two groups in our study and this is in agreement with Santos et al [12] and El-Mitwalli et al [11]; On the other hand Zheng et al [13] in his study found that smoking was significantly higher in patients with aspirin resistance, this may be due to different sample size and different methodology in their study as they did not exclude cardioembolic strokes
Summary
Arterioarterial microthromboembolism is an important factor in the pathogenesis of ischemic stroke. Platelet activation in cerebrovascular diseases is associated with recurrent stroke and death, and the inhibition of platelet function by antiplatelet drugs including aspirin lowers the risk of ischemic stroke [1]. TXA2 is a potent platelet agonist that, through stimulation of G protein-coupled receptors on platelets, brings about platelet aggregation and thrombus formation. Other factors have roles in platelet aggregation and thrombus formation, evidence shows that TXA2 is an essential contributor. TXA2 production is an early event platelet activation and potentiates other mediators with proaggregative effects. Platelet-derived TXA2 diffuses to subendothelial vascular smooth muscle, where it induces smooth muscle contraction and vasoconstriction
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callMore From: International Journal of Clinical and Experimental Neurology
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
