Introduction  

The carotid arteries are the main blood vessels that run along each side of the neck to the head.  One can feel the carotid artery pulse by placing fingers on either side of their windpipe. They carry oxygenated blood to the head including the eyes, face, and brain.

Anatomy

The carotid arteries have three layers of tissue:

  • The outer layer (Adventitia)
  • The muscular middle layer (Media)
  • The smooth central layer (Intima)
     

Function

Each of the two main carotid arteries divides in the neck into two branches: 

  • The external artery that moves blood to the neck, face and scalp 
  • Internal artery which transports blood to the front part of the brain. This area of the brain handles thought, speech, personality, sensory and motor functions.

The carotid bulb, also called the carotid sinus, is a broadening of a carotid artery at the central branching point. It has sensors which help to regulate blood pressure.

Associated symptoms & disorders

Various conditions can affect the carotid arteries including:

  • Carotid artery vacuities – It is an inflammation of the carotid artery because of an infection or an autoimmune condition  
  • Carotid hypersensitivity syndrome - In some people, applying pressure to the carotid bulb can cause a sudden drop in blood pressure and fainting  
  • Carotid artery embolism - A piece of embolus or cholesterol plaque may peel off from the carotid artery wall and move to the brain, resulting in a stroke
  • Carotid artery atherosclerosis – It is a gradual build up of cholesterol plaque on the carotid artery walls causing them to narrow. It is also known as carotid artery stenosis and can lead to a stroke.
  • Stroke - A sudden pause in blood flow to a part of the brain. A blood clot or cholesterol plaque can block a carotid artery and interrupt blood supply to the brain causing a stroke. 
  • Carotid artery aneurysm – A condition where a weak part of the carotid artery bulges out with each heartbeat like a balloon. It poses a risk for breaking and could result in severe bleeding or stroke.
  • Transient monocular blindness (Amaurosis fugax) – It is temporary blindness in one or both eyes. It occurs when a fragment of embolus or cholesterol plaque breaks off from the carotid artery wall and blocks blood flow the eye(s).
  • Carotid artery stenosis - Blockage or narrowing of one or both of these arteries reduces oxygenated blood flow to the brain. It can occur due to atherosclerosis (buildup of waste products like calcium and cholesterol plaque) inside the lining of the arteries.

Diagnosis of associated disorders

A health care professional can diagnose carotid arteries by reviewing the patient’s medical history and conducting carotid artery tests. These may include:

  • Carotid sinus massage 
  • Carotid artery ultrasound
  • Carotid artery angiography 
  • Magnetic resonance angiography (MRA scan)
  • Computed tomography angiography (CTA scan)
     

Treatment of associated disorders

The nature and extent of the carotid arteries condition determine the method of treatment.

  • Aspirin – A daily aspirin may lower the risk of a stroke or heart attack for people at high risk. Aspirin interferes with platelets, the components of blood that help blood to clot.Blood clots in the arteries can blocks blood flow the eyes.
  • Clopidogrel (Plavix) – It may be used with or without aspirin in patients at high risk for heart attack or stroke. Clopidogrel works like aspirin by also interfering with platelets. 
  • Statins – These cholesterol-lowering medicines may decrease the risk of stroke and heart attack in some people with stenosis or narrowing of the carotid artery. Statins are taken daily in pill form. 
  • Other medications - Treatment for temporal arteritis may consist of steroids (corticosteroid medications), methotrexate or tocilizumab ( a biologic drug). Tocilizumab is administered as an injection. It may be combined with steroids to reduce the amount of steroids that a patient needs.
  • Carotid endarterectomy (CEA) - The procedure removes blood clots and cholesterol plaque from the affected carotid arteries. A vascular surgeon slices open the carotid artery, removes the clots and buildups and stitches the artery closed.
  • Carotid artery angioplasty with stenting (CAS) - It is an option for patients who are unable to have carotid endarterectomy. The surgeon moves a wire through an artery in the leg up to the carotid artery, and stent or a small wire tube is expanded inside a narrowing of the carotid artery.