Antithrombotic Therapy For Stroke Prevention Research Articles

Selection of anticoagulants or antiplatelet-aggregating agents for prevention of stroke.

Stroke is one of leading causes of mortality and morbidity in the United States. Stroke prevention includes treatment of the stroke risk factors and long-term use of antithrombotic agents. Various agents have been studied for stroke prevention and other trials are ongoing. The aim of this article is to provide an overview of the recent guidelines, recommendations, and clinical trial results using antithrombotic therapy for stroke prevention.

Atrial fibrillation and stroke : concepts and controversies.

In 1985, patients with nonvalvular atrial fibrillation (AF) first entered randomized clinical trials that tested antithrombotic therapies for stroke prevention.1 2 3 Since then, >12 000 AF patients have been included in 25 trials that involved >40 randomized treatment comparisons (Table 1⇓). During this interval, we reviewed the pathogenesis and prevention of stroke in AF patients in 2 previous editorials in Stroke .4 5 Here, we offer commentary on selected concepts and controversies. View this table: Table 1. Randomized Trials of Antithrombotic Therapy in Atrial Fibrillation The prevalence of AF increases with age, affecting ≈5% of people at age 70 years. Although AF-associated stroke can occur at any age, it is predominantly a problem of the elderly. The median age of AF patients with stroke in population-based studies is ≈75 years; more than half are women. In people over age 75, AF is the most important single cause of ischemic stroke. This epidemiology is relevant when considering stroke prevention, because the risks of and ability to sustain preventive therapies are special problems for the very elderly. The left atrial appendage is a unique substrate for stroke. It is an elongated cul-de-sac lined with endothelium, a remnant of the embryonic atrium, trabeculated by pectinate muscles (Figure 1⇓). The contractility of the appendage is reduced in AF, but the degree varies widely and is an important determinant of stasis and thrombus formation. In AF patients, atrial thrombi almost always originate in the appendage, rather than in the smooth-walled atrium proper, and are not reliably detected with transthoracic echocardiography. Transesophageal echocardiography is much more sensitive for the detection of appendage thrombi in AF patients, but the complex structure is usually multilobed, projecting in unpredictable planes. This, coupled with the minute size of clinically important thrombi (2 to 3 mm), makes the exclusion of small …

Atrial Fibrillation and Stroke

Three new studies help clarify important clinical issues regarding antithrombotic therapy for stroke prevention in patients with atrial fibrillation. The European Atrial Fibrillation Trial compared the efficacy of oral anticoagulation, aspirin, and placebo for stroke prevention in patients with atrial fibrillation with a recent stroke or transient ischemic attack. The results of the Stroke Prevention in Atrial Fibrillation II trial, which compared the efficacy of warfarin and aspirin, provide new information regarding the risk of intracranial hemorrhage in elderly patients with atrial fibrillation. Finally, an analysis of pooled data from the first five randomized trials identified clinical features that are predictive of stroke risk in individual patients with atrial fibrillation. These studies address unanswered questions regarding atrial fibrillation and stroke and have significant implications for patient management.

Atrial fibrillation and stroke. Three new studies, three remaining questions

There new studies help clarify important clinical issues regarding antithrombotic therapy for stroke prevention in patients with atrial fibrillation. The European Atrial Fibrillation Trial compared the efficacy of oral anticoagulation, aspirin, and placebo for stroke prevention in patients with atrial fibrillation with a recent stroke or transient ischemic attack. The results of the Stroke Prevention in Atrial Fibrillation II trial, which compared the efficacy of warfarin and aspirin, provide new information regarding the risk of intracranial hemorrhage in elderly patients with atrial fibrillation. Finally, an analysis of pooled data from the first five randomized trials identified clinical features that are predictive of stroke risk in individual patients with atrial fibrillation. These studies address unanswered questions regarding atrial fibrillation and stroke and have significant implications for patient management. (Arch Intern Med. 1994;154:1443-1448)

Antithrombotic therapies for stroke prevention.

Aspirin is the most widely used antiplatelet agent, reducing nonfatal ischemic stroke by 22%. There is increasing evidence that the efficacy of aspirin may vary with the etiologic subtype of stroke. Although the cost and side effects have limited the use of ticlopidine, patients who are intolerant of aspirin and those experiencing transient ischemic attack or stroke during aspirin therapy should be given ticlopidine. Patients with atrial fibrillation have a five-fold increased risk of stroke and require prophylactic therapy with warfarin or aspirin. Aspirin is less effective than warfarin in preventing atrial fibrillation-associated stroke, but the higher risk of hemorrhagic complications and frequent monitoring associated with warfarin must be considered. Clinical and echocardiographic predictors of increased thromboembolic risk in atrial fibrillation patients have been identified and may direct the treatment choice.