Implantation of the stent
During treatment in the cardiac catheter laboratory, which is also called percutaneous coronary intervention, or PCI for short, the catheters and all other instruments are usually introduced via the groin. The patient is awake, only the puncture site where the doctor punctures the vessel is locally anesthetized and the patient is given a sedative. The inner walls of the vessel contain no pain receptors, so the cardiac catheterization and the implantation of the stent itself is not painful.
First, a guide wire is inserted into the punctured inguinal artery and advanced to the coronary arteries. For orientation in the body, it is important to note that the metal wire can be seen very clearly in an X-ray image. To check the position of the wire, the physician can therefore take X-rays again and again during the intervention and thus always knows exactly where it is located in the vessel.
Once the catheter has arrived at the right place, it can now be inserted over the wire. In order to be able to assess the degree of constriction exactly, contrast medium is injected through the catheter so that the vessel can be easily visualized. During the catheter examination of the heart, patients often perceive the administration of contrast medium as a warm feeling in the chest.
Once the position of the narrowing and the degree of constriction have been precisely determined, the decision to implant a stent is often made, since the stent can immediately expand the vessel again and the expansion created by the stent is kept open in the long term. Before a stent is implanted, a small balloon can be used to dilate the narrowed vessel. After selecting a suitable stent, the stent is then inserted on a balloon and advanced to the narrowed area of the vessel.
The vessel is dilated several times by inflating the balloon under very high pressure. Once the affected area has reached the desired inner diameter, the catheter and balloon are pulled out again and the stent remains in the previously constricted area, keeping it open.There are also stents that expand on their own, i.e. they do not have to be expanded to the desired diameter with a balloon, but when using such a stent, the vessel must first be sufficiently dilated. If everything went according to plan, the blood can now flow through the vessel again and supply all the cells with blood; the heart attack was successfully treated. After the intervention, the patient receives a pressure bandage in the groin to prevent bleeding at the puncture site.
