Introduction
Most done noncardiac vascular surgery is carotid endarterectomy. 55 years old man complaints of weakness over left side of the body. Patient is confused and disoriented. He is not a hypertensive and not a diabetic. MRI brain and MR angiography of carotid vessels was done. It showed reduction in calibre of intracranial portion of left internal carotid artery. Left middle cerebral artery is narrowed and shows reduced flow magnitude. Left middle cerebral artery shows flow through left posterior communicating artery. Al segment of left anterior cerebral artery appears hypoplastic. A2 and A3 segments of left anterior cerebral artery receive collateral flow through anterior communicating artery from contralateral side. [ figure 1] Soft tissue plaque seen in the left carotid bulb extending into the left internal carotid artery. Left internal carotid artery is narrowed (50%) from its origin throughout its course. [Figure 2] Sagittal T1 and axial T1 and T2 weighted images of the brain findings. The study reveals acute infarct evident by diffusion restriction and corresponding low ADC value in the left capsule-ganglionic region. Old infarct with gliosis noted in right capsule-ganglionic region. Acute infarct in the left capsule-ganglionic region. [Figure 3]. Nonspecific treatment was given, and patient recovered completely.
Discussion
Carotid endarterectomy is a surgical procedure done for the removal of the fatty deposits called plaque which builds-up inside the carotid artery and leads to narrowing of the artery. Carotid endarterectomy is usual surgical procedure when one or both carotid arteries are narrowed due to atherosclerosis caused by the build-up of fatty deposits called plaque.
Indication for Carotid endarterectomy are stroke, mini-stroke, or TIA (transient ischemic attack) with moderate (50-79%) blockage of a carotid artery in patients producing symptoms.
Even if the narrowing is 70% or greater without history of a stroke or a TIA carotid endarterectomy is done to reduce the risk of stroke risk. Carotid endarterectomy will be helpful if the stenosis is over 50% if the patient had a stroke or TIA. For the moderate strokes with ipsilateral severe stenosis of the internal carotid artery the Carotid endarterectomy is very much useful.1 Carotid artery stenosis of 50% or more with one or more transient ischemic attacks (TIAs) in the preceding 6 months. In progressive stroke with Carotid artery stenosis more than 70%. If artery stenosis narrowing is more than 60% even without symptoms in good-risk patients the Carotid endarterectomy can be done. In these asymptomatic patients’ surgical mortality and morbidity is less than 3%.2
Usually carotid endarterectomy (CEA) is done 6 to 8 weeks after acute stroke because the stroke can progress during post operative period. But this delay can produce an interval stroke rate of 9% to 15%.
The important risks associated with carotid endarterectomy. They are:
Stroke –2 % of the patients can develop during the post operative period and it will be higher for patients who have or had a stroke before the surgery.
Death –1% or less people will die following the surgery due to stroke or heart attack.
2 to 4 % people develop recurrence of stenosis the carotid artery and require surgery.
Risk factors are previous TIA, Diabetes, hypertension, and diabetes are other risk factors.
CEA is contraindicated are poor general condition with serious illness which will increase morbidity and mortality. It is also contraindicated in patients who present with major stroke or who had a major stroke recently with little or no recovery or a patient with altered level of consciousness. While doing emergency CEA in an acutely occluded carotid artery there is the risk of converting an ischemic cerebral infarct into a haemorrhagic infarct resulting in death.
Other procedure are carotid artery balloon dilatation and placement of stent. Long-term result from a successful stent placement is same as carotid endarterectomy.3 A preoperative carotid angiography is mandatory to identify the patients who would benefit from surgical intervention and reduce the postoperative mortality rate. We do not know the condition of the opposite artery. Many authors have documented that if an endarterectomy is considered it must be done within 1 hour.4
For older people more than 70 years Carotid angioplasty and for younger people carotid artery stenting (CAS) is preferable but CEA can be done. For older people CEA may be associated with improved outcome when compared to CAS when the arterial anatomy does not favour endovascular intervention; For younger patients both CAS and CEA are equal in terms of risk for procedural complications and long-term risk for ipsilateral stroke.
Prophylactic endarterectomy
For patients with asymptomatic carotid stenosis and contralateral carotid occlusion, prophylactic endarterectomy can be considered. Toronto study showed that the patients with asymptomatic neck bruits have annual stroke rate is 1-2%, but the annual rate of cardiac death is 2-4%.5
Management of Risk Factors for Carotid Endarterectomy
Hypertension
Most important factor in developing post operative hypertension is Preoperative hypertension. During surgery the common carotid artery, vagus nerve and the carotid sinus must be protected to prevent carotid baroreceptor dysfunction.6
Postoperative hypotension
If there is significant postoperative hypotension myocardial infarction must be ruled out.
Hyper perfusion syndrome
Sudden increase in cerebral blood flow will cause a severe unilateral headache that subsides with upright posture.
Intracerebral haemorrhage
Intracerebral haemorrhage is 0.6% of patients and occurs within 2 weeks after surgery.
Seizures
Seizures without postoperative cerebral infarction or post endarterectomy intracerebral haemorrhage is due to cerebral hyper perfusion syndrome with hypertensive encephalopathy. Another cause is brain oedema secondary to hyperperfusion.7
Cerebral hyper perfusion syndrome
After carotid-endarterectomy, patients may develop cerebral hyper perfusion syndrome. Patients will complain of headaches and hypertension. There may be seizures or focal neurological signs.8, 9 If patients develop hypertension after carotid endarterectomy, hypertension must be treated aggressively. 10
