Carotid stenosis: Description
Carotid stenosis is the term used by doctors to describe a narrowing (stenosis) of the carotid artery. There is a right and a left common carotid artery, which run along the sides of the neck from the chest towards the head. They divide into an internal and an external carotid artery (internal and external carotid artery) approximately halfway up the neck. The internal carotid artery (ACI) primarily supplies the brain with blood, while the external carotid artery (ACE) mainly supplies the scalp, face and upper neck organs with blood. Carotid stenosis is usually located in the area of the bifurcation.
Carotid stenosis: frequency
The frequency of carotid artery stenosis increases with the age of the patient. For example, only around 0.2 percent of men under 50 have at least half of their carotid artery narrowed. Up to a good two percent of over 60-year-olds and a good seven percent of over 80-year-olds have such asymptomatic carotid stenosis. Compared to women, men are affected about twice as often.
Carotid stenosis: symptoms
Carotid stenosis often causes no symptoms for a long time. Doctors then speak of asymptomatic carotid stenosis. When symptoms do occur, they can vary. Example:
- Visual disturbances such as double vision or visual field defects
- Speech disorders
- Headaches
- Dizziness attacks
These carotid stenosis symptoms can occur in attacks and persist for minutes to hours. If they subside, this is also referred to as a transient ischemic attack (TIA), i.e. a temporary lack of blood flow to the brain. If the symptoms persist or even increase over a longer period of time, it is a stroke (apoplexy, insult).
Carotid stenosis: causes and risk factors
The most common cause of carotid artery stenosis is vascular calcification (arteriosclerosis). With increasing age, deposits (plaques) form on the inner vessel walls – including the carotid artery. These deposits narrow the vessel. Risk factors such as smoking, high blood pressure or increased blood lipids accelerate the process. Eventually, small pieces of the plaque can break off, enter the cerebral vessels with the blood flow and constrict or completely block one of them. This results in reduced or no blood flow to the brain tissue (ischemia). If the downstream brain tissue is not quickly supplied with sufficient oxygen again, it dies – an ischemic stroke (cerebral infarction) occurs.
Carotid stenosis: risk factors
Various risk factors contribute to a narrowing of the carotid artery. These include
- Age and gender
- Elevated blood lipids (hyperlipidemia)
- Diabetes mellitus (diabetes)
- Smoking
- Obesity
Lifestyle therefore has a major influence on the development of carotid stenosis. People who eat a healthy diet, get enough exercise and do not smoke are less likely to develop carotid stenosis, or at least develop it later, than those who lead an unhealthy lifestyle.
Carotid stenosis: examinations and diagnosis
Carotid stenosis is usually detected during an ultrasound examination, but in some cases it can also be detected by typical symptoms. The first point of contact is usually your family doctor, who may refer you to a neurologist. A doctor will first ask you in detail about your medical history (anamnesis). Possible questions include, for example
- Do you suffer from high blood pressure or diabetes?
- Do you smoke?
- Do you suffer from vision problems from time to time?
Carotid stenosis: physical examination
The doctor will then examine you. He will feel your pulse on your neck and wrists. If there is carotid stenosis in the section of the common carotid artery, it may be difficult to feel the pulse. The doctor will then listen to your heart and great vessels with a stethoscope. If you have carotid stenosis, you may be able to hear flow noises above the carotid arteries.
Carotid stenosis: laboratory tests
Carotid stenosis: instrumental examinations
Ultrasound examinations (sonography) are particularly helpful in the diagnosis of carotid stenosis – more precisely, a special form of ultrasound: duplex sonography. It can be used to visualize both the blood flow in the vessels and the vessels themselves. This allows the severity of the stenosis to be determined and the type of narrowing to be identified. If the deposits on the vessel wall are rather firm and compact, they are less likely to detach than if they are friable and uneven.
Doctors often carry out further examinations to better assess the risk of a stroke. These include an ultrasound examination of the heart. The doctor can determine whether clots have formed in the heart that threaten to be washed into the carotid arteries and block them.
In addition, a long-term electrocardiogram (long-term ECG) is carried out in order to find possible indications of cardiac arrhythmia. These increase the risk of clots forming in the heart, which can block the carotid arteries.
An angiography may also be performed. In this vascular imaging procedure, the patient is injected with a contrast agent and the patient’s head is x-rayed. The blood vessels fill with contrast medium, which makes possible constrictions visible. Sometimes computed tomography (CT) or magnetic resonance imaging (MRI) is also used for this purpose.
Carotid stenosis: treatment
The aim of treating carotid artery stenosis is to prevent a stroke and ensure the blood supply to the brain. To do this, it is important to first minimize the risk factors. As a patient, you can make a significant contribution to this: get into the habit of leading a healthy lifestyle with sufficient exercise, a balanced diet and avoiding nicotine. Furthermore, your blood pressure and blood sugar should be optimally regulated. A healthy lifestyle also helps here. If necessary, your family doctor will prescribe additional medication (antihypertensives, blood sugar lowering medication).
To minimize the risk of a stroke, the doctor may also prescribe “blood-thinning” tablets. These so-called platelet aggregation inhibitors (such as acetylsalicylic acid = ASA) prevent blood clots (thrombi) from forming and blocking the blood vessels.
Carotid stenosis: surgical treatment
There is a risk that the operation itself could lead to a stroke. Therefore, the procedure should only be performed in medical centers that have sufficient experience with TEA. In addition, the treating doctors carefully weigh up the benefits and risks of the operation. Life expectancy, the degree of stenosis and any pre-existing conditions all play a role.
Another procedure that is used for carotid stenosis is carotid angioplasty with stent placement. This involves using a balloon catheter to expand the affected vessel from the inside and inserting a vascular support (stent) that expands on its own.
Carotid stenosis: course of the disease and prognosis
Carotid stenosis can remain undetected for a long time and cause no symptoms. This is dangerous, as the narrowing of the carotid artery usually increases over time, which increases the risk of a stroke. Every year, around 2 in 100 asymptomatic carotid stenoses that are discovered by chance cause a stroke. In addition, patients with carotid stenosis have an increased risk of suffering a heart attack.
You should therefore talk to your doctor in detail about treatment options. Changing your lifestyle with sufficient exercise and healthy eating can improve the prognosis of carotid artery stenosis.
