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Impaired Dynamic Cerebral Autoregulation as a Predictor for Cerebral Hyperperfusion After Carotid Endarterectomy: A
1Department of Vascular Ultrasonography, Xuanwu Hospital, Capital Medical University, Beijing, China; Beijing Diagnostic Center of Vascular Ultrasound, Beijing, China; Center of Vascular Ultrasonography, Beijing Institute of Brain Disorders, Collaborative Innovation Center for Brain Disorders, Capital Medical University, Beijing, China.
Insights
Dynamic cerebral autoregulation (dCA) can predict cerebral hyperperfusion (CH) after carotid endarterectomy (CEA). A lower ipsilateral phase in dCA measurements indicates a higher risk of developing CH, aiding in patient selection for CEA.
Area of Science:
- Neurology
- Vascular Surgery
- Physiology
Background:
- Cerebral hyperperfusion syndrome (CHS) is a serious complication following carotid endarterectomy (CEA).
- Identifying patients at high risk for cerebral hyperperfusion (CH) is crucial to mitigate CEA's reduced benefits.
- Dynamic cerebral autoregulation (dCA) is explored as a potential predictive marker for CH.
Purpose of the Study:
- To investigate the utility of dynamic cerebral autoregulation (dCA) in predicting cerebral hyperperfusion (CH) after carotid endarterectomy (CEA).
Main Methods:
- A prospective observational study involving 90 patients undergoing CEA.
- CH was defined as a ≥100% increase in middle cerebral artery mean flow velocity.
- dCA was assessed using transfer function analysis (phase, gain, coherence) in supine and squat-stand positions.
Main Results:
- Cerebral hyperperfusion (CH) occurred in 18 patients post-CEA.
- The CH group exhibited a significantly lower ipsilateral phase at very low and low frequencies compared to the non-CH group.
- A lower ipsilateral phase and a high preoperative peak systolic velocity ratio independently predicted postoperative CH.
Conclusions:
- The ipsilateral phase of dynamic cerebral autoregulation (dCA) demonstrates excellent predictive accuracy for cerebral hyperperfusion (CH) post-CEA.
- Lower ipsilateral phase values may serve as a valuable biomarker for identifying patients at risk of CH after CEA.
Objective:
Cerebral hyperperfusion syndrome (CHS) is a severe complication of carotid endarterectomy (CEA). Because cerebral hyperperfusion (CH) reduces the benefits of CEA, it is important to identify patients at high risk of developing CH. We investigated dynamic cerebral autoregulation (dCA) as a potential predictor of CH after CEA.
Methods:
In a prospective observational study of 90 patients, we defined CH as a ≥100% increase in the transcranial Doppler ultrasound-derived mean flow velocity of the middle cerebral artery compared to baseline, with or without clinical manifestations. We examined dCA in the supine position and during squat-stand maneuvers using the transfer function, analyzing phase, gain, and coherence. Logistic regression analysis and receiver operating characteristic (ROC) curves were used to assess the relationships between variables and outcomes.
Results:
Cerebral hyperperfusion (CH) occurred in 18 patients after CEA. The CH group had a lower ipsilateral phase for both body postures than the non-CH group at very low and low frequencies, respectively (both P < 0.01). Postoperative CH was independently associated with the preoperative peak systolic velocity (PSV)sten/PSVdis ratio and the ipsilateral phase in both body postures at a very low frequency. Receiver operating characteristic (ROC) curve analysis showed that the ipsilateral phase had excellent CH predictive accuracy in the supine position and squat-stand maneuvers at a very low frequency (areas under the curve: 0.809 and 0.839, respectively, both P < 0.001; cutoff values: 24.7 and 11.7, respectively).
Conclusions:
The lower ipsilateral phase may serve as a predictor of CH after CEA.
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