Objective: To assess whether patients with carotid artery occlusion (CAO) who have clinical features suggesting a haemodynamic origin have a poor haemodynamic or metabolic state of the brain.
Methods: In 117 patients with ischaemic symptoms of the eye or brain that were transient or at most moderately disabling and associated with a CAO, we compared CO(2) reactivity, quantitative flow measurement by magnetic resonance (MR) angiography, metabolic ratios measured by (1)H-MR spectroscopy, collateral blood flow patterns and the presence of infarcts of the borderzone type between patients grouped by the following clinical features: (1) presence or absence of at least one of the 'classical' haemodynamic symptoms: limb shaking, retinal claudication, precipitation of symptoms by exercise, by rising from a sitting or lying position, by transition from a cold to a warm environment, or by documented hypotension, and (2) symptoms having occurred after demonstration of the CAO or only before the occlusion was documented.
Results: Patients with (n = 16) and without (n = 101) one of the 'classical' haemodynamic symptoms did not differ in any of the measured indices. Patients with recurrent symptoms after documentation of the CAO (n = 56) had lower CO(2) reactivity (difference 8.3%, 95% confidence interval 0.1-16.5) than those with symptoms only before documentation of the occlusion (n = 61), whereas no significant differences were found in any of the other measured indices. The difference in CO(2) reactivity was no longer significant after adjustment for the interval between the patients' last symptoms and the CO(2) reactivity measurement.
Conclusion: In patients with CAO we could not find an association between symptoms that have been associated with hypoperfusion and a poor haemodynamic or metabolic state of the brain.