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Carotid Artery Disease Damilola Matthew Learning Outcomes Carotid Artery Disease Anatomy ● Describe the boundaries of the anterior triangle in the neck ● Describe the arterial trunks that arise from the arch of the aorta in the thorax ● Describe the origins, courses and major branches of the common, internal and external carotid arteries ● Describe the carotid sheath and list its contents Clinical ● What is carotid artery disease ● Describe the pathophysiology behind carotid artery disease ● How is carotid artery disease classified (severity) ● What are the risk factors ● What’s the clinical presentation- asymptomatic vs TIA vs stroke ● What other differentials should you consider ● What are the appropriate investigations- bloods, ECG, imagining, follow up ● What are the management options including CEA ● What are the potential complicationsAnatomyANTERIOR TRIANGLE OF THE NECK The anterior triangle of the neck is made up of: - The anterior border of the sternocleidomastoid muscle laterally - The inferior border of the mandible superiorly - The midline of the neck mediallyOrigins, Courses and Major branches of the common carotid artery • The right common carotid artery originates from the brachiocephalic trunk immediately posterior to the right sternoclavicular joint and is entirely in the neck throughout its course. • The left common carotid artery begins in the thorax as a direct branch of the arch of the aorta and passes superiorly to enter the neck near the left sternoclavicular joint. No branches At the superior edge of the thyroid cartilage each common carotid artery divides into its two terminal branches-the external and internal carotid arteriesOrigins, Courses and Major branches of the internal carotid artery Passes in the carotid sheath whilst in the neck It gives off no branches in the neck and enters the cranial cavity through the carotid canal in the petrous part of the temporal bone. Branches in the brain: •Ophthalmic artery – supplies the structures of the orbit. •Posterior communicating artery – acts as an anastomotic ‘connecting vessel’ in the Circle of Willis (see ‘Circle of Willis’ below). •Anterior choroidal artery – supplies structures in the brain important for motor control and vision. •Anterior cerebral artery – supplies part of the cerebrum. The internal carotids then continue as the middle cerebral artery, which supplies the lateral portions of the cerebrum. SBA What is the name of receptors in the carotid sinus? q Chemoreceptors q Electroreceptors q Baroreceptors q Ligand receptors q GPCRsOrigins, Courses and Major branches of the external carotid artery Begin giving off branches immediately after the bifurcation of the common carotid arteries - Superior thyroid artery - Ascending pharyngeal artery - Lingual artery - Facial artery - Occipital artery - Posterior auricular artery - Superficial temporal artery - Maxillary artery SBA What is the name of the only arterial branch of the external carotid artery that supplies intracranial structures? Hint: has to do with some of their branches later. q Maxillary Artery q Facial artery q Superficial temporal artery q Lingual artery q Occipital artery The carotid sheath and its contents Each carotid sheath is a column of fascia that surrounds the common carotid artery, the internal carotid artery, the internal jugular vein, and the vagus nerve as these structures pass through the neckClinical Carotid artery disease How does it present? What is it? Carotid artery stenosis is Carotid artery stenosis refers to usually asymptomatic. Usually, it is diagnosed after a TIA or stroke. narrowing of the carotid arteries in the neck, usually secondary A carotid bruit may be heard on to atherosclerosis. Plaques build up in the carotid arteries, reducing the examination. diameter of the lumen. There is a risk of parts of the plaque breaking away and becoming an embolus, travelling to the How is it classified? brain and causing an embolic stroke. *The swelling at the bifurcation of the The severity of carotid artery stenosis is categorised as: common carotid arteries, the carotid Mild – less than 50% reduction in sinus, produces turbulent blood flow. diameter This increases the risk of atheroma Moderate – 50 to 69% reduction in formation in this area, with the internal carotid most susceptible.* diameter Severe – 70% or more reduction in diameter SBA Whichofthe following is the most commonofa carotid bruit? q Atherosclerosis. q Vasculitis. q Trauma. q Vasculitis. q Hypertension. Carotid artery disease Presentation of stroke? o F Presentation of TIA? o A New 'tissue-based' definition is now used: a transient Give me some differentials? o S episode of neurologic o T dysfunction caused by focal brain, spinal cord, or retinal ischaemia, without acute Investigations? infarction. Bloods ECG Risk factors? o Increased age o Male sex Imaging o Smoking o Hypertension o Poor diet o Reduced physical activity o Raised cholesterol Carotid artery disease Management: Carotid endarterectomy Conservative Endarterectomy involves an incision in the neck, opening the carotid • Healthy diet and exercise • Stop smoking artery and scraping out the plaque. • Management of co- morbidities (e.g., Complications: - Stroke (around 2%) hypertension and diabetes) - Facial nerve injury causes facial weakness (often • Antiplatelet medications (e.g., aspirin, clopidogrel the marginal mandibular branch causing drooping of the lower and ticagrelor) lip) • Lipid-lowering medications - Glossopharyngeal nerve injury causes swallowing difficulties - Recurrent laryngeal nerve (a branch of the vagus nerve) injury (e.g., atorvastatin) causes a hoarse voice Surgical - Hypoglossal nerve injury causes unilateral tongue paralysis • Carotid endarterectomy • Angioplasty and stentingAortic Dissections Damilola Matthew SBA Whichofthe following layers are primarily involved inanaortic dissection? q Tunica externa and tunica media. q Tunica intima and anintramuralthrombus. q Tunica intima and tunica externa q Tunica intima and media. Learning Outcomes Clinical ● Recognise an aortic dissection as a tear in the tunica intima ● Discuss how aortic dissections can be classified (Stanford vs DeBakey) ● Recognise the main risk factors for aortic dissection ● Discuss the clinical features of aortic dissection and recognise other appropriate differentials ● Discuss the appropriate investigations (bloods, ECG, CT angio, echo) ● Discuss the various management options and how they vary depending on the type of dissection ● Recognise the possible complications following surgical interventionAORTIC DISSECTION Aortic dissection refers to when a break or tear forms in the inner layer of the aorta, allowing blood to flow between the layers of the wall of the aorta. With aortic dissection, blood enters between the intima and media layers of the aorta. A false lumen full of blood is formed within the wall of the aorta. Classification The Stanford system: Type A – affects the ascending aorta, before the brachiocephalic artery Type B – affects the descending aorta, after the left subclavian artery The DeBakey system: Type I – begins in the ascending aorta and involves at least the aortic arch, if not the whole aorta Type II – isolated to the ascending aorta Type IIIa – begins in the descending aorta and involves only the section above the diaphragm Type IIIb – begins in the descending aorta and involves the aorta below the diaphragm AORTIC DISSECTION Other features that may suggest aortic dissection are: Clinical presentation o Hypertension - Sudden onset, severe, “ripping” or “tearing” chest pain. o Differences in blood pressure between the arms (more than a - Pain may be in the anterior chest when 20mmHg difference is significant) o Radial pulse deficit (the radial pulse in one arm is decreased or the ascending aorta is affected, or the absent and does not match the apex beat) back if the descending aorta is o Diastolic murmur affected. The pain may change location (migrate) over time o Focal neurological deficit (e.g., limb weakness or paraesthesia) o Chest and abdominal pain o Collapse (syncope) o Hypotension as the dissection progresses Conditions or procedures that affect the aorta increase Conditions that affect the the risk of a dissection: Risk factors? o Increased age connective tissues can also o Bicuspid aortic valve o Male sex increase the risk of a o Coarctation of the aorta o Smoking dissection: o Aortic valve replacement o Hypertension o Ehlers-Danlos Syndrome o Coronary artery bypass o Marfan’s Syndrome graft (CABG) o Poor diet o Reduced physical activity o Raised cholesterol SBA A man aged around 60 with a background of hypertension, presenting with a sudden onset tearing chest pain. What is the gold standard for the potential diagnosis? q MRI q Non-contrast CT q Ultrasound chest q Xray q CT angiogram AORTIC DISSECTION Diagnosis: - An ECG and chest x-ray are often used to exclude other causes (such as myocardial infarction), although they may be normal and falsely reassuring. Myocardial infarction can occur in combination with aortic dissection, and treatment of the myocardial infarction (e.g., thrombolysis) can cause fatal progression of the aortic dissection. - CT angiogram is usually the initial investigation to confirm the diagnosis and can generally be performed very quickly. - Transoesophageal echocardiography (TOE) - MRI angiogram provides greater detail and can help plan management but often takes longer to get. Differentials - WHAT DO YOU EXPECT TO FIND? - Angina (Stable and unstable) - WHAT BLOODS OR EXRA INVESTIGATIONS WOULD YOU DO? - Myocardial infarction - Cardiac tamponade - Pulmonary embolism - Myocarditis Management and complication Aortic dissection is a surgical emergency and needs immediate involvement of experienced seniors, vascular surgeons, anaesthetists and intensive care teams. There is a very high mortality. Analgesia (e.g., morphine) is required to manage the pain. Blood pressure and heart rate need to be well controlled to reduce the stress on the aortic walls. This usually involves beta-blockers. Complication o Myocardial infarction Surgical intervention from the vascular team will depend on the type of aortic o Stroke dissection. o Paraplegia (motor or sensory impairment in Type A may be treated with open surgery (midline sternotomy) to remove the the legs) section of the aorta with the defect in the wall and replace it with a synthetic o Cardiac tamponade graft. The aortic valve may need to be replaced during the procedure. o Aortic valve regurgitation Type B may be treated with thoracic endovascular aortic repair (TEVAR), with a o Death catheter inserted via the femoral artery inserting a stent graft into the affected section of the descending aorta. Complicated cases may require open surgery.Thanks to our partners!@supta_uk @SUPTAUK www.supta.uk