Patterns of cerebrovascular reactivity in patients with carotid artery occlusion and severe contralateral stenosis
M Matteis1, F Vernieri, C Caltagirone
1IRCCS 'S. Lucia', Roma, Italy.
Insights
Cerebrovascular reactivity, measured by breath-holding index (BHI), is significantly reduced in symptomatic patients with carotid steno-occlusive disease compared to asymptomatic individuals and controls. This indicates impaired cerebral hemodynamics are linked to stroke symptoms.
Area of Science:
- Neurology
- Vascular Medicine
- Medical Imaging
Background:
- Altered cerebral hemodynamics are implicated in stroke development in patients with carotid disease.
- Understanding cerebrovascular reactivity is crucial for assessing stroke risk.
Purpose of the Study:
- To investigate cerebrovascular reactivity patterns in patients with internal carotid occlusion and severe contralateral carotid stenosis.
- To examine the relationship between these patterns and patient symptomatology.
Main Methods:
- Transcranial Doppler ultrasound was used to assess cerebrovascular reactivity to hypercapnia.
- The breath-holding index (BHI) was measured in the middle cerebral arteries of 42 patients and 40 controls.
Main Results:
- Symptomatic patients showed significantly decreased BHI on the occluded side compared to asymptomatic patients and controls (P<0.0001).
- Asymptomatic patients also had significantly lower BHI than controls (P<0.0001).
- On the stenotic side, BHI was significantly higher in asymptomatic patients than symptomatic ones (P<0.0001).
Conclusions:
- Cerebrovascular reactivity in severe bilateral carotid steno-occlusive disease appears strongly correlated with the presence of symptoms.
- Further research is needed to determine the role of cerebral hemodynamics in therapeutic strategy planning for these patients.
Abstract:
There is evidence suggesting that among other factors, an alteration in cerebral hemodynamics plays a relevant role in the occurrence of strokes in patients with carotid disease. The purpose of this study was to investigate patterns of cerebrovascular reactivity in patients with internal carotid occlusion and severe contralateral carotid stenosis and their relationship with symptomatology. Using transcranial Doppler ultrasound, cerebrovascular reactivity to hypercapnia in middle cerebral arteries was evaluated with the breath-holding index (BHI) in 42 patients with internal carotid occlusion and severe contralateral carotid stenosis and in 40 control subjects. A significant decrease of BHI on the occluded side was observed in symptomatic patients with respect to asymptomatic ones (0.12+/-0.1 vs. 0.75+/-0.4, P<0.0001) and with respect to the control group (1.11+/-0.1, P<0.0001). The difference was also significant between asymptomatic patients and controls (P<0.0001). Breath-holding values on the stenotic side were significantly higher (P<0.0001) in asymptomatic patients (1.01+/-0.2) with respect to symptomatic ones (0.39+/-0.1). A significant difference (P<0.0001) was also present between controls and symptomatic patients. The pattern of cerebrovascular reactivity in patients with severe bilateral carotid steno-occlusive disease seems to be strictly dependent on the presence of previous symptoms. Further studies are needed to investigate whether the study of cerebral hemodynamics in patients with bilateral carotid artery disease is important for planning therapeutic strategies.
