|
|
 |
 |
|
|
| Different causes underlie internal and cortical border-zone infarcts |
|
03 February 2006
Internal border-zone (IBZ) infarcts are most often caused by haemodynamic compromise, whereas most cortical border-zone (CBZ) infarcts have an embolic origin, research published in the journal Stroke shows. "These findings suggest that patients with difference types of border-zone infarct would require different therapeutic approaches to prevent early clinical deterioration," say the South-Korean study authors.
From 946 patients with ischaemic stroke, the research team from Ajou University in Suwon, led by Dr Seok Yong, identified 45 patients with IBZ infarcts and 75 with CBZ infarcts. Patients with an IBZ infarct were more likely to have at least 75% stenosis or occlusion in the middle cerebral artery than those with a CBZ infarct. A rosary-like pattern of infarcts, which is believed to be indicative of haemodynamic failure, was observed in 60% of patients with IBZ infarcts, compared with just 19% of CBZ infarct patients. In contrast, 65% of patients with CBZ infarcts displayed small cortical infarcts, which are thought to represent embolic infarcts that originate in the heart or large arteries, compared with 29% of patients with IBZ infarcts. Taken together, these findings suggest that a haemodynamic mechanism is the main cause of IBZ infarcts, while embolic mechanisms are most commonly responsible for CBZ infarcts.
The CBZ lies relatively closer to the cortical surface, where penetrating arteries originate, and has better chance for collateral supply through leptomeningeal and dural anastomoses, which makes it more resistant to decreased cerebral perfusion. Importantly, patients with IBZ infarcts were significantly more likely to suffer clinical deterioration, and 32% of these patients had a poor outcome after 90 days compared with 5% of those with a CBZ infarct.
"These results suggest that more intensive care is warranted in the initial stages of an IBZ infarct, with the aim of ameliorating the vascular insufficiency," the researchers write. "In contrast, many of CBZ infarct patients may suffice with therapeutic approaches such as antiplatelet agents and statins that reduce microembolism and stabilise atheromatous plaques."
Reference:
Stroke 2006; online publication.
 Back to selection |
|
 |
|
|
|
