A randomized trial of aspirin or heparin in hospitalized patients with recent transient ischemic attacks. A pilot study.

Abstract

In a randomized pilot study we compared the efficacy of temporary anticoagulation with intravenous heparin sodium to the efficacy of aspirin in preventing cerebral infarction in hospitalized patients with recent (<7 days) transient ischemic attacks (TIAs). Fifty-five patients (33 men, 22 women) aged 36-81 (mean 62.7) years met entry criteria and agreed to participate. Symptoms prompting hospitalization were referable to the carotid distribution in 43 patients (34 hemispheric, nine retinal); 12 patients had vertebrobasilar distribution TIAs. Twenty-seven patients received heparin and 28 received aspirin. Patients were treated until surgery or until long-term medical therapy was instituted, 3-9 (mean 5.5) days in the heparin group and 3-15 (mean 5.8) days in the aspirin group. Recurrent TIAs occurred in eight patients given heparin and in seven treated with aspirin. Infarction occurred in one patient in the heparin group and in four patients in the aspirin group (three brain, one retinal infarction). Initial symptoms in these five patients were referable to the carotid distribution in two and to the vertebrobasilar distribution in three. All patients but the one with a retinal infarction had recurrent TIAs prior to stroke. Our pilot study suggests that hospitalized patients with recent TIAs are at high risk for recurrent TIAs (15 of 55, 27%) and brain infarction (five of 55, 9%) and that patients with recent vertebrobasilar distribution TIAs have a marginally significantly higher risk (odds ratio 6.83, 95% confidence interval 0.

Stroke Risk After Posterior Circulation Stroke/Transient Ischemic Attack and its Relationship to Site of Vertebrobasilar Stenosis

“…7 Its results were consistent with our data showing a high early recurrent stroke risk in symptomatic VB stenosis.…”

“…8 In addition, 14 studies were identified, which only included patients with VB stenosis, without a control group with no stenosis. Two studies reported the risk of stroke in patients with extracranial vertebral artery stenosis only (see the online-only Data Supplement references I and II), 8 in intracranial VB stenosis9 (see the online-only Data Supplement references III through IX), and in 7 the risk relating to site of stenosis was unclear 2,3,7,8 (see the online-only Data Supplement references X through XII). No studies provided direct comparative data on the risk of extracranial versus intracranial stenosis in the same study population.…”

Definition and Evaluation of Transient Ischemic Attack

“…66 -74 Numerous studies also have shown that the short-term risk of stroke is particularly high, with most studies finding risks exceeding 10% in 90 days. 7,13,21,[75][76][77][78][79][80][81][82][83][84] Risk is particularly high in the first few days after TIA, with most studies finding that one quarter to one half of the strokes that occur within 3 months occur within the first 2 days. 7,21,75,79,82,84,85 For example, studies in northern California and Oxfordshire found the risk of stroke in the first 24 hours after TIA to be Ϸ4%, 75,86 which is about twice the risk of myocardial infarction or death in patients presenting with acute coronary syndromes (Ϸ2% at 24 hours).…”

Early risk of stroke after transient ischemic attack: back to the future

“…4 In a 1978 study, 40% of patients with a single TIA had a stroke within 1 month. 5 About 10 years later, 2 studies demonstrated a 9% risk of stroke within 6 days after a TIA, 6 and a 4.4% risk at 30 days. 7 The authors of these 2 studies respectively concluded that "patients with recent TIAs are at high risk for … brain infarction" and that "[t]he risk of stroke is greater immediately after TIA, which has important implications for clinical practice."…”

“…Robust analyses of attributable risk due to TIAs as a function of age should be the subject of future research, as should the continued search for short-term treatments to prevent stroke. 4,6 …”