Catheterization and angioplasty are two similar cardiology procedures but with different purposes. Dr. Loubad, cardiologist, explains the difference, what they are used for and what each one consists of.
What is catheterization and what is it used for?
Catheterization consists of introducing a catheter, which consists of a small cylindrical tube, into the artery and making it reach the aorta, where the coronary arteries originate, and injecting a contrast with the coronary arteries.
Nowadays it is performed under local anesthesia, with a puncture. It can be radial, femoral or other routes but, at present, it is almost always performed radially and, on some occasions, when it cannot be performed radially, the femoral route is used. With the patient lying in bed, sometimes a relaxant is applied so that the patient is not nervous, but will remain awake. Thus, local anesthesia is applied to the wrist and an introducer is placed and, through this, a wire is passed with the catheter which, when it reaches the aorta, where the coronary arteries begin, a contrast will be injected to visualize the arteries and the blood by means of X-rays.
Thus, the coronary arteries (which are basically three) that surround the heart in the form of a crown (for this reason they are called coronary arteries) are observed through screens. With several projections with the machine, the three coronary arteries are viewed: the anterior descending, circumflex and right coronary arteries, and their corresponding branches.
With this first part, which is the diagnostic catheterization, the condition of the coronary arteries is assessed and a decision is made as to whether a diagnostic angioplasty is also needed or whether the patient is really in need of surgery or medical treatment.
What is angioplasty and why is it performed?
Angioplasty is practically the same as catheterization, but the catheters are changed for slightly thicker ones, which go to the aorta where the coronary arteries originate or exit. With this new catheter, the coronary arteries are observed where the coronary obstruction is and how to unblock it. This unblocking is done by passing a very fine wire through the coronary artery at the end of the artery.
Actually, obstructions can be partial or complete: when an obstruction is 100% complete, if it is acute it is easy to open, but if it is chronic it is more difficult. On the other hand, if it is not obstructed, it is easier to pass with the guide.
A very small balloon is passed over the guidewire, one millimeter, one and a half millimeters, two millimeters, two and a half millimeters or three millimeters in diameter. This is introduced into the obstructed area, inflates on the outside and dilates the obstruction: this opens the artery to implant the stent. This stent is usually implanted because, since the artery wall has been slightly deconstructed, otherwise it often becomes blocked again. The stent is a kind of metal mesh mounted on a balloon. When we reach the area where we have dilated, we inflate the balloon inside the stent, the mesh is opened, it remains attached to the wall of the artery, we deflate the balloon, we remove it and the mesh remains attached to the coronary artery, thus completing the angioplasty. It is a painless procedure.
What are the risks involved?
The risks of catheterization and angioplasty are, in general, very low. Actually nowadays, with technological advances, with really new materials, it has been possible to reduce the risks to a minimum.
Most of the risks are vascular, local. If it starts in the radial artery, in general there would only be a hematoma, the hand would swell or there could be radial dissection. On very few occasions the hand has to be operated on, but these are rare cases.
There are usually more complications via the femoral artery, since it is a larger artery. There may be hematomas which, on occasions, may be more important, but in general they are minimal.
There may also be tachycardia, chest pain, the artery may be blocked, there may be an infarction, but these are minimal complications and, above all, they depend on the patient. A patient who comes from home for catheterization and angioplasty is not the same as a patient who comes from the emergency room with a heart attack and major problems. The risk, to some extent, depends on each patient and his or her clinical situation, but in general the risks are really minimal and the procedure is quite safe.
How long is the post-operative period for catheterization and angioplasty?
The post-operative period is very short. In the case of diagnostic catheterization, when we have not had to perform angioplasty or we have not placed a stent or dilated the artery, through the radial route, normally in three or four hours the patient goes home and does not have to take any special care. The first day it may be recommended not to make any effort with the hand where the catheterization has been performed, but the following day the patient can lead a normal life.
When the diagnostic catheterization is performed via the femoral artery, the patient normally has to stay overnight, although sometimes a closure can be made with special devices and the patient can leave the same day. When it is an angioplasty, the postoperative period generally lasts 24 hours: the first four hours the patient is monitored, the electrocardiogram, blood pressure and if he/she is in pain. After these four hours, in general, no monitoring is required and the patient can go to a normal hospital room.
The following day, if the hand or leg has a good hematoma and everything is all right, the patient can go home and return to normal life in a progressive manner, depending on the clinical situation prior to the catheterization. For example, a patient who comes for angina pectoris can normally start to lead a normal life immediately. If a patient undergoes angioplasty after a heart attack, he/she usually has to recover for more than three or four weeks and progressively return to an active life, since a heart attack requires a period of time for the heart to heal.
How does the life of a patient who undergoes catheterization or angioplasty change?
It will change depending on how they were and their clinical situation before the intervention. Patients, for example, who have angina pectoris, at the slightest effort it hurts them, since they present obstructions of 90, 95, 99%. In reality, the patient’s quality of life improves spectacularly: he begins to walk without pain and can do sports. As the patients tell us, they feel wonderful.
There are other patients who have pain when walking two or three floors, or with more effort. Once we fix the problem they start to have a very important quality of life and their self-esteem improves because they see that they can do sports, they can have a normal life, they can have a normal sexual activity. It is a very important benefit for them.
But not only quality of life, it also improves survival. In some patients who have more significant involvement in a main artery, such as the common trunk, and many of them also have dysfunction or involvement of the heart muscle when their arteries are repaired, percutaneous revascularization improves the contractility of the heart and increases survival in the sense that they live longer.