Preprocedural Planning
Carotid artery disease may be either symptomatic or asymptomatic. Symptoms include transient ischemic attack (TIA), stroke, stroke in evolution, or crescendo TIA. In symptomatic patients, imaging should begin with carotid duplex ultrasonography (US). Carotid duplex imaging uses qualitative and quantitative information to determine the severity of carotid artery stenosis with an overall accuracy of 80-97%.
If duplex imaging demonstrates severe stenosis or ulcerative plaque that correlates with clinical symptoms, no further carotid imaging is required in most cases. In patients with mild-to-moderate disease (< 50%) on duplex imaging and hemispheric TIAs, alternative causes may be sought with magnetic resonance angiography (MRA), computed tomography (CT) angiography (CTA), or catheter-based angiography of the chest, neck, and brain. These advanced imaging techniques may also be indicated for operative planning in the following situations [11] :
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Low carotid lesion (suggested by low common carotid artery [CCA] velocities)
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High carotid lesion (above C2)
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Previous carotid endarterectomy (CEA)
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History of other major neck operation (eg, radical neck dissection, laryngectomy, or tracheostomy)
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Cervical fusion
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Poor neck mobility
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Previous neck irradiation
A study by Qin et al suggested that low or high preoperative serum cortisol levels may adversely affect the stability of carotid plaque in patients with carotid artery stenosis who undergo CEA, and this effect may be associated with an increased risk of stroke. [12]
Patient Preparation
Anesthesia
Patients undergoing CEA are kept on nil per os (nothing by mouth) status from midnight the day before surgery.
Regional anesthesia using deep or superficial cervical blocks is commonly performed and allows direct observation of the patient for signs of cerebral ischemia, thereby reducing the need for intraoperative carotid shunting. However, use of regional anesthesia is contraindicated if either the patient or the surgeon has issues with anxiety or communication. Local anesthetic techniques result in less blood pressure lability.
Overall morbidity and mortality are not significantly affected by the choice of anesthetic technique. Although the type of anesthesia used for CEA does not impact outcomes, regional anesthesia is associated with shorter operating times, anesthetic times, and time to discharge. [13] In a 2021 Cochrane review, no difference in perioperative stroke or death was seen when regional and general anesthesia were compared for CEA. [14]
The main alternative to regional anesthesia in this setting is general anesthesia. General anesthesia has the advantage of reducing cerebral metabolic demand and increasing cerebral blood flow. Endotracheal intubation also provides good airway control and reduces patient and physician anxiety. Nasotracheal intubation can be used to facilitate exposure of the distal cervical segment of the internal carotid artery (ICA) in patients with high carotid artery stenosis or in patients undergoing reoperation.
Antiplatelet therapy should be continued throughout the perioperative period. Perioperative use of vasopressors or vasodilators to maintain blood pressure in the patient’s optimal physiologic range is critical.
Positioning
The patient is placed in the supine position with the head turned away from the side of the operation. A beach-chair configuration offers greater comfort to awake patients and provides excellent exposure while decreasing venous pressure. The neck is moderately extended by placing a shoulder roll or by tilting back the neck extension of the bed.
The endarterectomy site is prepared and draped from the midline in an area encompassing the clavicle, the sternal notch, and the mandible. Proper lighting is essential, and loupe magnification is routine.
Monitoring & Follow-up
As a rule, if no complication occurs, patients are discharged home on postoperative day 1. They continue their antiplatelet and secondary preventative therapy.
At 2-6 weeks after CEA, carotid duplex US should be performed. If the findings from duplex imaging are satisfactory, another duplex study should be done 6 months to 1 year later, then every year thereafter. If there is evidence of moderate contralateral disease or recurrent carotid artery stenosis, scanning may be performed at intervals of 6-12 months. [15]
The 2018 guidelines from the Society for Vascular Surgery (SVS) recommended that after CEA, surveillance with duplex US should be carried out at baseline and every 6 months for 2 years and annually thereafter until the patient is stable. [16] The first duplex study should be done soon after the procedure (preferably ≤ 3 months) to establish a posttreatment baseline. Surveillance should be maintained at some regular interval (eg, every 2 years) for the life of the patient.
In the Carotid Revascularization Endarterectomy versus Stenting Trial (CREST), restenosis and occlusion occurred infrequently and rates were similar after CEA and carotid artery stenting (CAS) during 2 years of follow-up. Female sex, diabetes, and dyslipidemia independently predicted restenosis or occlusion after the two procedures, and smoking predicted an increased rate of restenosis in patients who underwent CEA but not in those who underwent CAS. [17]
In a retrospective review of SVS Vascular Registry database subjects who underwent CEA or CAS from 2004 to 2011, Geraghty et al found that the 30-day outcomes of both procedures were significantly affected by the type of symptom presentation. [18] Presentation with stroke and TIA predicted higher rates of periprocedural complications, whereas TMB presentation with transient monocular blindness (TMB) predicted a periprocedural risk profile similar to that of asymptomatic disease.
Long-term data from the randomized International Carotid Stenting Study (ICSS) comparison of CAS and CEA in patients with symptomatic carotid stenosis indicated that the two procedures are comparable with respect to long-term functional outcome and risk of fatal or disabling stroke. [19]
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Carotid endarterectomy: operative techniques.
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Anatomy of internal carotid and vertebral arteries.
