Stroke is one of the leading causes of death in addition to heart attack and cancer and is the most common reason for long-term care in adulthood. In Germany, approximately 270, 000 people suffer a stroke each year, excluding unnoticed, "silent" cerebral infarctions. The consequences of strokes - from weakness in arms or legs to paralysis and even death - are well known. But how does that happen?
Narrowing of the carotid artery
About 18 percent of strokes (30, 000) are due to a narrowing of the carotid artery. The carotid arteries run up and down the head on both sides of the neck, supplying blood to the brain. They are called carotis, in German "sleeping" artery, because a disturbance of the blood flow robs the human consciousness. Correspondingly dangerous is a narrowing or even occlusion of the carotid arteries, the so-called carotid stenosis.
Causes of Carotid Stenosis
The main cause of carotid stenosis is arteriosclerosis. It usually occurs in people over the age of 60 years. The risk factors include - as with all vascular diseases - high blood pressure, too much blood fat, diabetes, smoking, lack of exercise and obesity.
The gradual deposition of fat on the vessel walls leads to a narrowing of the carotid artery. The blood does not flow freely to the brain - the result is symptoms such as circulatory, visual and speech disorders, feelings of numbness and tingling, paralysis, headache and dizziness. Over time, plaques (clots) develop on the vessel walls.
It really gets dangerous when they come loose and are carried along with the bloodstream into the brain: The plaques can close smaller arteries and thus lead to neurological damage to stroke and death. Around one million people in Germany live with more than 50 percent carotid stenosis.
How does the doctor determine if there is a carotid stenosis?
Simply by listening to the stethoscope or using for example ultrasound, angiography or computed tomography. A certain calcification is part of the natural aging process. In these cases, the doctor prescribes only one drug that improves blood flow and prevents the formation of blood clots.
If stroke has already occurred, or if there is a higher-grade carotid stenosis, an operation has usually been carried out (carotid TEA). The surgeon opens the carotid artery, separates it from the bloodstream, removes the calcification, cleans the vessel and sews it together again. In some cases, a "patch" of a piece of vein or plastic material is sewn in (grafting).
Innovative treatment option
The operation can now be spared selected patients: Your carotid arteries are extended by carotid stenting. This minimally invasive treatment can usually be done under local anesthesia and does not require a skin incision on the neck. It puts less strain on the vessel and the surrounding cervical nerves, is not associated with an operating trauma, and can also reach those vessels that are inaccessible to surgery (for example, near the base of the skull).
How does a carotid stenting work?
The principle is simple: width, safety, support. The necessary instruments are inserted from the groin into the carotid artery via a catheter. A balloon widens the constriction. In the process, plaques can come loose - if they reach the brain, there is an acute risk of stroke!
To avoid this, the doctor often introduces a safety system: A small umbrella unfolds in the vessel and catches the loose parts. Subsequently, a stent (mesh-like wire) is used to support the vessel wall. With a small amount of contrast, the doctor will check if the closure has been opened successfully.
If the findings are inconspicuous, balloon, catheter and the closed umbrella are removed together with the dangerous loose plaques and tissue parts. Only the stent stays in the body, so that the carotid artery does not narrow again. Over time, the tissue of the arterial wall grows around the vascular support, providing additional reinforcement of the artery. With all the preparations and the control, the procedure takes about 45 minutes.
Benefits for the patients
- No surgery, much less traumatic
- Local anesthesia instead of general anesthesia
- No surgical scar on the neck
- Objectively and subjectively shorter recovery times, that is, the patient can be discharged home faster.
Important study results
A recent study (SAPPHIRE) confirms the positive results of minimally invasive carotid stenting in patients with significantly increased surgical risk. This is good news for these patients with, for example, severe heart or lung disease. Carotid stenting gives them just as good results as their particularly risky operation.
For the time being, all other patients will continue to be advised to undergo endarterectomy or, in less cases, drug therapy unless other study results are available.
Availability of carotid stenting
Carotis stenting is offered nationwide in Germany. Not only university hospitals can perform the surgery, but any radiological, vascular surgery and cardiology practices, provided that the local staff has an appropriate training. Patients wondering where to get the best treatment can use the number of procedures as an assessment criterion: the more experience and routine a team of physicians has gained, the greater the success of the treatment.
Carotid stenting is another treatment option for narrowed carotid arteries. More and more doctors and patients are consciously opting for this form of stroke prophylaxis. Success and complication rates as well as long-term results of stent-assisted carotid angioplasty are currently being compared with the operative procedure in further prospective randomized trials. When deciding which treatment is right for you, you should weigh the pros and cons with your doctor.