17 May 2004 Recurrent ischemic stroke associated with severe aortic atherosclerosis Patients with a brain embolism and severe aortic atheroma are at higher risk of a recurrent stroke than are patients with less severe aortic lesions. Dr Shigeru Fujimoto (National Cardiovascular Center, Osaka, Japan) and colleagues measured intima media thickness (IMT) and extent of aortic arch atherosclerotic plaque in stroke patients who did not have significant cerebral artery lesions. Their results were published online ahead of print on April 29, 2004 in Stroke [1]. Previous studies have found aortic arch atherosclerosis to be associated with embolic brain infarction. However, many of these patients also have arterial or cerebral occlusive disease that can be an embolic source for ischemic stroke. In this longitudinal follow-up study Fujimoto et al sought to determine the relationship between the characteristics of aortic arch atherosclerotic lesions and brain infarction in patients both with and without proembolic heart conditions. The researchers recruited 283 stroke patients with brain embolism but without significant occlusive lesions in their cerebral arteries. Intima-media thickness (IMT) was measured to determine the severity of atheroma, and the extension of the aortic lesions was determined by echocardiography. IMT and extent of atheroma important factors The researchers found a wall thickness of >4.0 mm in a total 67 (25.3%) of patients, and in 51 patients the aortic lesions were both >4.0 mm and extended to the origin of at least one branch. Recurrent stroke occurred in 32 (11%) patients during a mean follow-up period of 3.4 years. Of these, 13 had an aortic atheroma >4.0 mm and 20 had an atheroma that extended to the origin of at least one branch. Although patients who experienced stroke recurrence were significantly older than those without recurrence (p<0.01), there were no other significant differences in baseline characteristics between these groups. Compared to patients without stroke recurrence, those with recurrence were more likely to have severe aortic atheroma (22% vs 41%, p<0.05), aortic atheroma extending to the branches (39% vs 63%, p<0.1), or both (16% vs 38%, p<0.01). The incidence of stroke recurrence was 9.1% per person-year in patients with an aortic atheroma >4.0 mm compared to 2.9% per person-year in patients with an atheroma <4.0 mm. After taking age and hypertension into account, severe atheroma extending to the aortic branches remained a significant, independent predictor of ischemic stroke recurrence [Table 1]. Table 1. Multivariate analysis of stroke recurrence by severity of aortic arch atheroma*
The authors discuss the results of the study, noting that there was no significant difference between the types of secondary medical prevention - antiplatelet vs anticoagulant agents - in terms of stroke recurrence. They do note that the incidence of stroke recurrence in patients with an atheroma >4.0 mm was lower than that found by the French Study of Aortic Plaques in Stroke Group [2], and that more patients in the present study were treated with anticoagulants (45% vs 20%) than in the French study. "These factors could effectively explain the difference in the rate of stroke recurrence," Fujimoto and colleagues write, but while "the difference in the use of anticoagulants between the studies is interesting, our study was not designed as a therapeutic trial." The researchers conclude that "a severe atheroma extending to the aortic branches has a significant association with ischemic stroke in patients with or without heart disease," and that both the thickness and degree of extension of the atheroma were important factors. "The optimal medical therapy (antiplatelet agents or anticoagulant agents) for patients with severe aortic atheroma remains to be determined by randomized trials," they comment. Erin O'Connell
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