Background and methods: The cause of cerebral infarction is obscure in up to 40 percent of patients with this disorder who are studied prospectively. In this investigation, we determined the frequency of ulcerated plaques in the aortic arch and explored the part they may play in the formation of cerebral emboli. Using an autopsy data bank, we studied the prevalence of ulcerated plaques in the aortic arch in 500 consecutive patients with cerebrovascular and other neurologic diseases who were studied at autopsy.
Results: Ulcerated plaques were present in 26 percent of the 239 patients with cerebrovascular disease but in only 5 percent of the 261 patients with other neurologic diseases (P less than 0.001). After we controlled for age and heart weight, the adjusted rates were 16.9 percent and 5.1 percent, respectively (adjusted odds ratio, 4.0; 95 percent confidence interval, 2.1 to 7.8; P less than 0.001). Among the patients with cerebrovascular disease, the prevalence of ulcerated plaques in the aortic arch was 28 percent in the 183 patients with cerebral infarcts and 20 percent in the 56 patients with brain hemorrhage. The prevalence of ulcerated plaques was 61 percent among the 28 patients with no known cause of cerebral infarction, as compared with 22 percent among the 155 patients with a known cause of cerebral infarction (P less than 0.001). After adjustment for covariates, the prevalence was 57.8 percent among patients with no known cause of cerebral infarction and 20.2 percent among those with a known cause (adjusted odds ratio, 5.7; 95 percent confidence interval, 2.4 to 13.6; P less than 0.001). The presence of ulcerated plaques in the aortic arch was not correlated with the presence of extracranial internal-carotid artery stenosis, suggesting that these were two independent risk factors for stroke.
Conclusions: Ulcerated plaques in the aortic arch may play a part in causing cerebral infarction, especially in patients in whom cerebral infarction has no known cause.