Antiplatelet Treatment in Ischemic Stroke Treatment

Abstract

Antiplatelets represent a diverse group of agents that share the ability to reduce platelet activity through a variety of mechanisms. Antithrombotic agents are effective in the secondary prevention of ischemic strokes. Most strokes are caused by a sudden blockage of an artery in the brain (called an ischaemic stroke) that is usually due to a blood clot. Immediate treatment with antiplatelet drugs such as aspirin may prevent new clots from forming and hence improve recovery after stroke. Several studies have evaluated the role of one antiplatelet agent, aspirin, in reducing stroke severity. The International Stroke Trial (IST) of 20,000 patients with acute stroke from other countries. In this study there was a significant 14% proportional reduction in mortality during the scheduled treatment period (343 [3.3%] deaths among aspirin-allocated patients vs 398 [3.9%] deaths among placebo-allocated patients; 2p = 0.04). There were significantly fewer recurrent ischaemic strokes in the aspirin-allocated than in the placebo-allocated group (167 [1.6%] vs 215 [2.1%]; 2p = 0.01) but slightly more haemorrhagic strokes (115 [1.1%] vs 93 [0.9%]. Few studies examined the role of ticlopidin in acute stroke setting the results showed treatment with ticlopidine improved the neurologic outcome. In the Examining the Safety of Loading of Aspirin and Clopidogrel in Acute Ischemic Stroke and TIA (LOAD) study, 40 consecutive ischemic stroke patients were treated with 325 mg of aspirin and 375 mg of clopidogrel within 36 hours of symptom onset. Overall, 37.5% (n = 15) of the patients had an improvement of 2 or more points on the NIHSS 24 hours after antiplatelet administration. The antiplatelet efficacy of aspirin in preventing secondary stroke was established by three studies conducted in the late 1980s and early 1990s: the Swedish Aspirin Low-dose Trial (SALT) trials have demonstrated that aspirin-even in doses as low as 30 mg/day-reduces secondary stroke, MI, or vascular death in patients with. Clopidogrel and aspirin have been used in combination in patients with diverse arterial vascular diseases However, combinations of antithrombotic agents do not necessarily improve clinical efficacy and are typically associated with increased toxicity.

Clopidogrel Plus Aspirin Prevents Early Neurologic Deterioration and Improves 6-Month Outcome in Patients With Acute Large Artery Atherosclerosis Stroke

“…Recurrence results in poor prognosis in patients with ischemic stroke, and antiplatelet therapy has been recommended for the secondary prevention of stroke in patients with a history of noncardioembolic stroke or TIA to reduce nonfatal MI, nonfatal stroke, or vascular death. 39,40 In the present study, we also found that dual antiplatelet therapy was superior to aspirin alone for the prevention of END and RIS. Dual antiplatelet therapy, compared with aspirin alone, was not associated with an increased incidence of hemorrhage.…”

“…The role of antiplatelet drugs may be different in each subtype of stroke. 40 Several studies have reported that combination therapy with clopidogrel and aspirin is more effective than aspirin alone in reducing microembolic signals and recurrent stroke in patients with predominantly intracranial symptomatic stenosis. 20,21 However, among patients with recent lacunar strokes, the addition of clopidogrel to aspirin therapy did not significantly reduce the risk of recurrent stroke but did significantly increase the risk of bleeding and death.…”

Functional enhancement of platelet activation and aggregation by erythrocytes: role of red cells in thrombosis

“…29 Furthermore, ASA administration has been shown to reduce stroke and myocardial infarction severity. 30,31 However, individuals that experience recurrent thrombotic events while undergoing aspirin therapy may be classified as "aspirin resistant". ASA resistance is thought to be caused by the inability of ASA to exert inhibitory effects on platelet activation.…”

Current Perspectives in Post-stroke Cognitive Impairment

“…[49][50][51] However, there is little evidence suggesting that non-steroidal anti-inflammatory drugs (NSAIDs) are effective in preventing cognitive decline following stroke.…”