What is a stent?
A stent stabilizes narrowed vessels after they have been dilated. The aim is to prevent the vessel from becoming blocked again. In addition, the vascular support made of metal or synthetic fibers fixes vascular deposits, smoothes the surface of the interior of the vessel by pressing it against the vessel wall and thus improves the blood flow in the vessel. The most common variant is the “heart stent” on the coronary arteries, which is used in patients with coronary heart disease. Here, the stent has now replaced bypass surgery. The surgeon uses a thin plastic tube (catheter) to insert the stent, which can be tightly compressed thanks to its fine-mesh grid structure. There are different types.
Self-deploying stent
Balloon-expanding stent
The folded stent is attached to a so-called balloon catheter, which can be inflated as part of a vasodilatation procedure known as percutaneous transluminal angioplasty (PTA). The metal mesh of the stent then retains its expanded shape.
Coated stents
In addition to uncoated stents (bare metal stents, BES), drug-eluting stents (DES) are now being used more and more frequently. The released medication prevents the formation of new cells and thus counteracts re-occlusion (re-stenosis). Research is also being carried out into completely bioresorbable stents (BRS), which degrade after some time, for example to avoid the increasing risk of occlusion by blood clots if the stent remains in place for a longer period of time.
When is a stent implantation performed?
A stent is always used when a permanent expansion of an occluded vessel or hollow organ cannot be guaranteed by simply widening the vessels (percutaneous transluminal angioplasty, PTA).
This is most frequently the case in the following situations
- Narrowing of the coronary arteries in coronary heart disease (CHD)
- Circulatory disorders in the arm and leg arteries in peripheral arterial occlusive disease (PAD)
- Stroke due to narrowing of the carotid arteries (carotid stenosis)
- Dilation of the aorta (aortic aneurysm)
- Narrowing of the renal arteries (renal artery stenosis)
- Narrowing of ducts (e.g. bile duct stenosis)
How do vessels become blocked?
However, a blood clot (thrombus) can also block a vessel without arteriosclerosis. Three factors are responsible for the formation of a thrombus (Virchow triad): a change in the blood composition, a slowing of the blood flow and changes in the vessel walls. A so-called embolism can also cause a vascular occlusion. Thrombi detach from their original location and travel through the bloodstream into narrower vessels, where they cause the blockage. However, a stent does not usually need to be inserted in the event of such thromboembolic events.
What is done during stent implantation?
After administering a local anaesthetic, the doctor first punctures a blood vessel close to the surface, usually the artery in the arm or groin, and inserts a “sheath”. Under X-ray control, he pushes a special catheter through this to the constriction of the blocked vessel and injects contrast medium to visualize the constriction again.
In PTA, a folded balloon is placed at the tip of the catheter. As soon as this is placed at the constriction, it is filled with a mixture of saline and contrast medium and expands. The balloon presses the deposits and calcifications against the vessel wall and thus opens the vessel.
Once the stent insertion is complete, the doctors remove all catheters and the sheath and apply a pressure bandage. This must remain in place for several hours.
What are the risks of stent implantation?
In addition to the general surgical risks such as infections, wound healing disorders and minor bleeding, the following complications can occur in rare cases:
- Cardiac arrhythmia during the procedure
- Vascular occlusion
- Vascular perforation with life-threatening blood loss
- Heart attack or stroke
- Stent thrombosis: The stent becomes blocked by a blood clot
The complications ultimately depend heavily on the location of the stent implantation. The patient’s pre-existing conditions also influence the complication rate.
What do I need to consider after stent implantation?
Within the first few weeks after the stent operation, a doctor will examine you again thoroughly. He will listen to your heart and lungs and carry out various tests, such as a resting ECG, blood pressure measurements and laboratory tests. These are repeated at regular intervals.
Life with a stent
A stent does not restrict you in your everyday life. Examinations such as magnetic resonance imaging (MRI) are also possible. Not smoking, regular physical activity and a balanced diet are helpful in preventing vasoconstriction caused by plaques. If you manage to get the risk factors for arteriosclerosis under control, you may not need a new stent.
Sport with a stent
Regular physical activity has the following positive effects on the body:
- improves the oxygen supply to the body
- lowers blood pressure
- regulates blood sugar levels
- regulates blood lipid levels
- reduces fat deposits
- counteracts inflammatory processes
- promotes healthy body weight
- reduces stress hormones
A stent is not an exclusion criterion for sport. The stent does not cause any restrictions. However, it is important to choose a type of sport that does not place excessive strain on the cardiovascular system and is adapted to the underlying disease.
Moderate endurance training is particularly suitable for most heart patients. This includes, for example
- (fast) walking
- Walking on a soft mat/on sand
- hiking
- Walking and Nordic walking
- jogging
- Cross-country skiing
- Step aerobics
- Cycling or ergometer training
- Climbing stairs (e.g. on the stepper)
Starting training after stent surgery
How long should I rest after a stent has been inserted? That depends on the underlying disease. After a mild myocardial infarction, the patient can usually slowly return to activity after about a week. After a severe heart attack, on the other hand, they will be treated in hospital for longer. The first therapeutic mobilization usually begins there.
Note: If you have a heart condition, you should always discuss the start of training with the doctor treating you. They know your case and your physical constitution and can make an appropriate recommendation.
When starting training, it is important to start at a low intensity and increase it slowly.
