Prevention of stroke

Diener HC, Cunha L, Forhes C, Sivenius J, Smets P, Lowenthal A. European Stroke Prevention Study. 2. Dipyridamole and asetylsalicylic acid in the secondary prevention of stroke. J Neurol Sci 1996 143 1-13. 

Gent M. A systematic overview of randomised trials of antiplatelet agents for the prevention of stroke, myocardial infarction and vascular death. In Hass WK, Easton ID, editors. Ticlo-pidine, platelets and vascular disease. New York Springer-Verlag 1993 p99-116. 

Warfarin has not been adequately studied in non-cardioembolic stroke, but it is often recommended in patients after antiplatelet agents fail. One small retrospective study suggests that warfarin is better than aspirin.30 More recent clinical trials have not found oral anticoagulation in those patients without atrial fibrillation or carotid stenosis to be better than antiplatelet therapy. In the majority of patients without atrial fibrillation, antiplatelet therapy is recommended over warfarin. In patients with atrial fibrillation, long-term anticoagulation with warfarin is recommended and is effective in both primary and secondary prevention of stroke.12 The goal International Normalized Ratio (INR) for this indication is 2 to 3. 

The most recent CHEST guidelines continue to recommend aspirin therapy for the secondary prevention of stroke.12 The... 

The main indications for aspirin as a platelet aggregation inhibitor are prevention of stroke in patients with cerebrovascular disease, prevention of myocardial infarct in patients with unstable angina or after myocardial infarction. For the prevention of myocardial infarction in someone with documented or suspected coronary artery disease, doses as low as 75 mg daily (or possibly even lower) are sufflcient. 

SHEP Co-operative Research Group Prevention of stroke by antihypertensive drug treatment in older persons with isolated systolic hypertension final results of the Systolic Hypertension in the Elderly Programme (SHEP). JAMA 1991 265 3255-64. 

A major focus of drug development has been to develop orally active anticoagulants that do not require monitoring. Rivaroxiban is the first oral factor Xa inhibitor to reach phase III clinical trials. The safety and efficacy of rivaroxiban appears to be at least equivalent, and possibly superior, to LMW heparins for prevention of deep vein thrombosis no routine monitoring is required. This drug is also in clinical trials for treatment of deep vein thrombosis and prevention of stroke in atrial fibrillation. 

Norris JW. Antiplatelet agents in secondary prevention of stroke a perspective. Stroke. 2005 36 2034-2036. 

In view of the perceived benefit of aspirin in the secondary prevention of stroke and myocardial infarction, two large trials involving physicians as subjects were initiated to study the effect of aspirin in the primary prevention of arterial thrombosis. In the American study, 22,000 volunteers (age 40 to 84 years) were randomly assigned to take 325 mg of aspirin every other day or placebo. The trial was halted early, after a mean follow-up of 5 years, when a 45% reduction in the incidence of myocardial infarction and a 72% reduction in the incidence of fatal myocardial infarction were noted with aspirin treatment. However, total mortality was reduced only 4% in the aspirin group, a difference that was not statistically significant, and there was a trend for a greater risk of hemorrhagic stroke with aspirin. Thus, the prophylactic use of aspirin in an apparently healthy population is not recommended at this time, unless there are risk factors for cardiovascular disease. 

Diener HC. Antiplatelet drugs in secondary prevention of stroke lessons from recent trials. Neurology 1997 49 S75-S81. 

Olsson SB, Halperin JL. Prevention of stroke in patients with atrial fibrillation. Semin Vase Med 2005 5 285-292,... 

Sherman D (2002) Long-term Anticoagulation Therapy in Prevention of Stroke. Curr Treat Options Neurol 4 411-416... 

Stroke is a global health problem affecting approximately 750,000 people annually in the United States alone and ranks as the third leading cause of death and the most common cause of disability in most developed countries. Traumatic brain injury (TBI) accounts for an estimated 34% of all injury-related deaths in the United States. Stroke and TBI can produce both focal and widespread damage to the brain, which can yield acute and chronic impairments of sensory, motor, and cognitive functions. Because of their enormous medical and socioeconomic impact, a tremendous research investment is being made in the treatment and prevention of stroke and TBI. 

The antiplatelet/antithrombotic activity of dipyridamole has been demonstrated in laboratory and in animal models, and has been shown to inhibit platelet aggregation and vessel-wall thrombogenesis [9-11]. Dipyridamole has been given either alone or with aspirin in the management of myocardial infarction and stroke. For the secondary prevention of stroke or transient ischemic attack, the drug may be given as a modified-release preparation in a dose of 200 mg twice daily. Dipyridamole administered intravenously results in a marked coronary vasodilation and is used in stress testing in patients with ischemic heart disease [5]. 

Mrs SL should be given aspirin 300 mg rectally daily from admission, once ischaemic stroke has been diagnosed. Dipyridamole SR 200 mg b.d. may be added when Mrs SL can swallow, following recommendations for secondary prevention of stroke (ESPRIT Study Group, 2006). 

Aspirin is used in secondary prevention of stroke as it reduces platelet aggregation and the clotting tendency of blood. 

Rothwell PM (2005). Prevention of stroke in patients with diabetes mellitus and the metabolic syndrome. Cerebrovascular Diseases 1 24-34... 

Some of the association between atrial fibrillation and stroke must be coincidental because atrial fibrillation can be caused by coronary and hypertensive heart disease, both of which may be associated with atheromatous disease or primary intracerebral hemorrhage. Although anticoagulation markedly reduces the risk of first or recurrent stroke, this is not necessarily evidence for causality because this treatment may be working in other ways, such as by inhibiting artery-to-artery embolism, although trials of warfarin in secondary prevention of stroke in sinus rhythm have shown no benefit over aspirin (Ch. 24). 

Diener HC, Cunha L, Forbes C et al. (1996). European secondary prevention study 2 dipyridamole and acetylsalicylic acid in the secondary prevention of stroke. Journal of Neurology Science 143 1-13 European Atrial Fibrillation Trial Study Group (1993). Secondary prevention in non-rheumatic atrial fibrillation after transient ischaemic attack or minor stroke. Lancet 342 1255-1262... 

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