Coronary angiography is an examination that allows the professional to visualize the arteries of the heart known as the coronaries. As a result, it is possible to demonstrate the presence of obstructions like the presence of atheromatous plaques in these arteries.
The first coronary angiography was performed in 1945.
The patient does not need an appointment. The cardiologist usually requests this exam after meeting with the patient.
Certain circumstance require an urgent coronary angiography, such as a myocardial infaction while other situations, like during a hospitalization due to unstable angina or other cardiovascular conditions, necessitate it as semi-urgent.
Before the exam
In general, the hospital calls the patient for pre-admission. When the patient arrives at the hospital, a blood test and an electrocardiogram are done.
The examination is explained to the patient and any questions he or she might have are answered at this point. In general, this pre-admission takes place a few weeks preceding the intervention.
After having been informed of the ricsks associated with this examenation, the patient must sign a consent form. These risks are details further in this text. At this point, the doctors considers that the benefits outweight the risks of the examination.
The day of the exam
Usually, a patient will remain hospitalized only one day for this examination.
The patient must have an empty stomach and must not take any medication as of midnight the night before unless otherwise specified in pre-admission.
Upon arrival, the patient must remove all clothing and put on a hospital jacket. A nurse then installs one or two catheters in a vein through which intravenous fluids and medications can be administered as needed during the examination.
Any hair on the right or left wrist as well as on both groins will be shaved off to allow the installation of the catheters in the artery chosen by the cardiologist.
Preparation in the examination room
At the scheduled time, the patient is brought to the examination room on a stretcher.
During the examination, the nurses and the doctor take the same precautions as in the operating room in order to avoid bacteria entering the patient's body (sterile environment). The doctor and his team are dressed in blue or green and wear surgical masks and bonnets.
The room temperature is cool, even cold, to allow radiology equipment to run smoothly. A sterile blanket covers the patient during the examination to minimize discomfort related to room temperature.
Preparation for the exam is often longer than the exam itself.
There are 2 arteries that ensure the circulation of the hand, which has a particularity. Indeed, connections exist between these 2 arteries. If one of them blocks, the other can do its job. A test with the hand is often done to verify the reciprocity between the 2 arteries or, in other words, to check if the connections work properly.
In some cases, the radial artery (artery of the wrist) may be unusable; we will then use the femoral artery (artery of the groin) to access the heart.
The benefits of going through the radial artery are the decreased risk of bleeding and the possibility of getting up one to two hours after the exam.
Iodine fluid is injected into the coronaries to make them visible on the screen using X-rays, medical imaging staff wear clothing to protect themselves daily.
After preparing the material for the exam, the nurse disinfects the groin and right or left wrist depending on availability and examination. Once these areas have dried out, she places a sterile blanket on the patient and plugs the devices that will be used for the examination. The patient must limit his movements as much as possible from this moment on.
During the exam
The doctor shows up and the examination begins.
The nurse gives medication to the patient to help him or her relax and to reduce pain during the puncture.
The doctor chooses the artery in which he will introduce the catheters.
In this case the artery of the wrist is used.
The doctor performs local anesthesia to minimize the pain.
A small incision is made and, with a hollow needle, he punctures the chosen artery.
Setting up the entrance
A plastic tube, called catheter, is installed in the artery and keeps this entrance accessible throughout the examination. The rest of the exam is painless.
It is the same when the artery of the groin is used.
Through the introducer, we pass a long metallic wire and a catheter, this long plastic tube, to reach the coronary arteries.
Once in place, the wire is removed and the catheter is manipulated to access the coronary arteries.
The creation of images
When the catheter is in place, an iodine dye is injected.
This allows to clearly see the path of the substance inside the coronary arteries on the images captured by the radiological device that moves around the patient.
These images highlight the presence of partial or complete blockages and give information on the size of the arteries, their position and their anatomical particularities.
The work of the heart
Once all images of the coronary arteries are taken, the examination is almost complete.
Most of the time, the cardiologist will take an additional image to visualize the function of the left ventricle, one of the four heart chambers. This last image makes it possible to evaluate the contraction and the work of the patient's heart.
During this injection, the patient feels a great burst of heat, descending from the head to the hips, which can give the impression of urinating. This sensation is normal; the injected iodinated contrast product causes it.
After the exam
The catheters are removed. A compressing wristband is placed on the wrist of the patient to prevent bleeding while the small hole in the artery clogs.
This bracelet is loosened gradually in the following hours.
If the procedure is performed through the femoral artery, a compression bandage is installed to prevent and control the bleeding. The leg must remain stable for four to six hours.
Most of the time, an arterial closure device can also be used to seal the small hole in the artery instead of compressing manually.
The cardiologist who performed the examination gives the results to the patient and can advise him on the next steps. The discovery of blockages leads to a variety of treatments, ranging from prescribing medications to angioplasty or bypass surgery.
The patient can request a copy of the results for another doctor
The patient may request that a copy of the results be sent to his or her family doctor or to any other doctor.
All you have to do is give the doctor's name and contact information to the staff. The patient can do this at the beginning or end of the exam.
Risks of the procedure
Coronary angiography is a very safe exam, but it carries risks like any other medical procedure done inside the human body.
The risks of death related to this examination are estimated at less than 1 in 10,000. Other risks of major complications, such as a stroke, an infarction, kidney problems or the need for an urgent surgery urgent, are evaluated at less than 1 in 1,000.
The risk of minor complications such as bleeding, or hematoma, that is, a build-up of blood, is estimated at about 1%.