Stroke, along with heart attack and cancer, is one of the most common causes of death and the most common reason for needing care in adulthood. In Germany, approximately 270,000 people suffer a stroke each year, not including unnoticed, “silent” cerebral infarctions. The consequences of strokes – from weakness in the arms or legs to paralysis and even death – are well known. But how does it happen?
Narrowing of the carotid artery (carotid artery).
About 18 percent of strokes (30,000) are due to narrowing of the carotid artery. The carotid arteries run upward into the head on both sides of the neck and supply blood to the brain. They are called carotid arteries because a disturbance of the blood flow deprives the person of consciousness. Narrowing or even blockage of the carotid arteries, known as carotid stenosis, is correspondingly dangerous.
Causes of carotid stenosis
The main cause of carotid stenosis is hardening of the arteries (atherosclerosis). It usually occurs in people over the age of 60. As with all vascular diseases, risk factors include high blood pressure, excessive blood fat, diabetes, smoking, lack of exercise and obesity. The gradual deposition of fat on the walls of the blood vessels leads to a narrowing of the carotid artery. Blood no longer flows freely to the brain – resulting in symptoms such as impaired circulation, vision and speech, numbness and tingling, paralysis, headaches and dizziness. Over time, plaques (clots) form on the walls of the blood vessels. It becomes really dangerous when these break loose and are carried into the brain with the bloodstream: The plaques can block smaller arteries, leading to neurological damage and even stroke and death. In Germany, about one million people live with more than 50 percent carotid stenosis.
How does a doctor determine if carotid stenosis is present?
Quite simply by listening with a stethoscope or using, for example, ultrasound, angiography, or computed tomography. Some calcification is part of the natural aging process. In these cases, the doctor only prescribes a drug that improves blood flow and prevents the formation of blood clots. If a stroke has already occurred or if there is a higher degree of carotid stenosis, surgery has usually been performed up to now (carotid TEA). In this procedure, the surgeon opens the carotid artery, cuts it off from the bloodstream, removes the calcification, cleans the vessel and sews it back together. In some cases, a “patch” made from a piece of vein or plastic material is sewn in (grafting).
Innovative treatment option
Select patients can now be spared surgery: Their carotid arteries are dilated via carotid stenting. This minimally invasive treatment can usually be done under local anesthesia and does not require a skin incision in the neck. It puts less stress on the vessel and surrounding cervical nerves, does not involve surgical trauma, and can reach vessels that are not amenable to surgery (for example, near the base of the skull).
How does carotid artery stenting work?
The principle is simple: widen, secure, support. By catheter – from the groin – the necessary instruments are pushed into the carotid artery. A balloon dilates the narrowing. Plaques can break loose in the process – if they reach the brain, there is an acute risk of stroke! To prevent this, the physician often introduces an additional safety system: a small umbrella unfolds in the vessel and catches the loose parts. A stent (mesh-like wire) is then inserted to support the vessel wall. The physician uses a small amount of contrast medium to check whether the occlusion has been successfully opened. If the findings are unremarkable, the balloon, catheter and collapsed umbrella are pulled out along with the dangerous loose plaques and tissue fragments. Only the stent remains in the body to prevent the carotid artery from narrowing again. Over time, the tissue of the artery wall grows around the stent, providing additional reinforcement to the artery. With all the preparations and monitoring, the procedure takes about 45 minutes.
Benefits for patients
- No surgical intervention, much less traumatic
- Local anesthesia instead of general anesthesia
- No surgical scar on the neck
- Objectively and subjectively shorter recovery times, meaning the patient can be discharged home sooner.
Key study findings
A recent study (SAPPHIRE) demonstrates the positive results of minimally invasive carotid stenting in patients with significantly increased surgical risk. For these patients with, for example, severe heart or lung disease, this is good news. Carotid stenting achieves just as good results for them as surgery, which is particularly risky for them. All other patients will continue to be advised to undergo endarterectomy or, in milder cases, drug therapy for the time being – until other study results are available.
Availability of carotid stenting
Carotid stenting is available nationwide in Germany. Not only university hospitals can perform the procedure, but any radiology, vascular surgery, or cardiology practice, as long as the staff there has appropriate training. Patients wondering where best to seek treatment can use the number of procedures as an evaluation criterion: The more experience and routine a medical team has accumulated, the greater the success of treatment.
Conclusion
Carotid stenting is another treatment option for narrowed carotid arteries. More and more physicians and patients are consciously opting for this form of stroke prophylaxis. The success and complication rates as well as long-term results of stent-assisted carotid angioplasty are currently being compared with the surgical procedure in further prospective randomized trials. When deciding which treatment option is right for you, you should carefully weigh the pros and cons with your physician.
