Ms DH is a 74-year-old lady presented to the Vascular team for elective left carotid endarterectomy (CEA).
Ms DH was first presented to the team following a transient ischaemic attack in 2011. At workup investigation, her right internal carotid artery (RICA) was found to be stenosed of 90 to 99% and left internal carotid artery (LICA) stenosis of 50 to 69%. She proceeded to have right CEA at the time, and has since regularly attended vascular clinic for follow up monitoring.
On her recent visit, her LICA stenosis has increased to 70 to 80%. She was asymptomatic, but however advised by the consultant surgeon to undergo carotid endarterectomy.
Patient has background of asthma, COPD, hypertension, type 2 diabetes mellitus, osteoarthritis, and gout. Her surgical history includes right CEA 6 years ago, and bilateral knee cartilage removal. She is of ASA grade 3.
Patient is an occasional drinker and an ex-smoker of 24 years with 35 pack-years history.
Pathophysiology of the condition
Carotid stenosis is an atherosclerosis disease caused by build-up of atheroma plaque inside the artery wall. These atheromatous plaques are composed of soft grumous lipid core, mainly of cholesterol. Over time, the plaques can mechanically block the blood vessel. Risk factors of atherosclerosis are generally divided into two big groups of constitutional and modifiable risk factors. Constitutional risk factors include strong family history, age, and gender. Modifiable risk factors are hyperlipidaemia, hypertension, cigarette smoking, and diabetes mellitus. The pathogenesis of disease is supported by the response-to-injury hypothesis. Atherosclerosis is said to be a chronic inflammatory response of arterial wall to endothelial injuries (caused by the risk factors stated). The atherosclerotic plaques can either be stable or vulnerable depending on the person fitness and health status. Vulnerable plaques particularly have thin fibrous cap, large lipid cores, and dense inflammatory infiltrates; causing it to be more susceptible to acute plaque changes such as rupture, ulcer, or erosion. Vessel thrombosis of ruptured plaque could potentially cause catastrophic events such as cerebrovascular accident
Choice of surgical procedure
Carotid endarterectomy is a surgical procedure consists of removing the diseased part of the carotid artery. CEA is performed through a neck incision. Vessels are first localised and mobilised; and the internal, common, and external arteries then clamped. The vessel is then opened and shunt is placed. Once shunt is placed, carotid plaque is then freed and removed. The endarterectomised surface must be inspected before repair to ensure removal of any residual plaques or debris. Repair of vessel can be done either primarily or patching the vessel with vein or Dacron.
Alternative treatment options
Alternatively, carotid stenosis can be managed conservatively with aspirin and statin. Risk of stroke is significantly lower with surgical and medical treatment in comparison to medical therapy alone.
In severe stenosis of 90 to 99%, patient would usually be advised on having endarterectomy whether they are symptomatic or asymptomatic. In general, symptomatic patients would usually be advised on surgery while those asymptomatic will be treated conservatively. Recommendation of endarterectomy in asymptomatic patients varies on their histories and co-morbidities.
Expected and potential outcomes
Patient is expected to be stenosis-free post operatively. However, incidence of recurrent stenosis post-endarterectomy ranges from 1 to 37% and is generally due to either hyperplasia of the myointimal cell postoperatively, or recurrent atherosclerosis. Patients are required to continue medical management and have a healthy life style. As Ms DH already had an experience of right CEA previously and recovered well, she is expected to have same recovery process with her left CEA.
In summary, atherosclerosis is a common disease we would usually see in the current society especially in those with poor health and diet control. Healthy lifestyle is important regardless of age and gender. Smoking is especially the enemy of the vascular system and awareness need to be continuously raised among the public for a healthier community.