BOSTON — Intracranial plaques and stenoses are highly prevalent in fatal ischemic stroke patients, according to the results of a study presented at the annual meeting of the American Academy of Neurology.
The findings suggest that intracranial atherosclerosis might not be as rare a condition as previously believed and that intracranial stenoses in particular might be the cause of fatal brain infarction in many cases, according to Dr. Mikael Mazighi of the Hôpital Lariboisière in Paris.
Dr. Mazighi and colleagues performed a systematic analysis of intracranial and extracranial arteries, the aortic arch, and the heart in 339 consecutive autopsies of ischemic stroke patients. The analysis also included clinical history, risk factors, imaging data, and general autopsy reports for each patient. The control group comprised hemorrhagic stroke patients.
The prevalence rates of intracranial plaques and stenoses in the brain infarction patients were significantly higher, at 62% and 42%, respectively, compared with 49% and 18% in patients with brain hemorrhage, Dr. Mazighi reported. Additionally, in more than 5% of the ischemic stroke victims with at least one stenosis of 30%–75%, the stenosis was considered the cause of the infarction, he said.
Diabetes and male gender were significantly associated with intracranial plaques and stenosis in multivariate analysis, said Dr. Mazighi. In addition, a history of previous myocardial infarction was significantly associated with intracranial plaques, and previous stroke was associated with intracranial stenosis, he said.
The high prevalence of the intracranial atherosclerotic findings and the apparent causal role of moderate stenoses in fatal ischemic stroke observed in this investigation suggest that the prevalence of intracranial atherosclerosis is likely underestimated, probably because of the lack of appropriate diagnostic procedures, said Dr. Mazighi. The frequency and role of intracranial artery plaques in stroke patients should be reevaluated using new intravital imaging techniques, he said.