Borderzone infarct subtypes: preliminary study of the presumed mechanism.

Whether watershed infarcts and internal junctional infarcts have different mechanisms remains unknown. Of 493 consecutive patients with ischemic stroke or transient ischemic attack, 26 had 1 watershed infarct or more (8 anterior and 21 posterior) and 18 had 1 internal junctional infarct or more. Patients with watershed infarcts were more likely to have arterial hypertension [95% confidence intervals of odds ratio (CIOR): 1.04-6.15] and internal carotid artery stenosis > 50% (95% CIOR: 1.03-7.12) than patients without borderzone infarcts. Patients with internal junctional infarcts were more likely to have heart diseases than patients without borderzone infarcts (95% CIOR: 1.46-10.52). This preliminary study suggests that both subtypes of borderzone infarcts probably have different mechanisms.