Coronary Angiogram

Coronary angiography involves a dye test looking at the arteries to the heart to establish whether there are any blockages. It remains the Gold Standard and is the only way of conclusively ruling out blockages or narrowing’s of the coronary arteries.  

What is an Angiogram?

An angiogram involves selectively injecting radio opaque contrast directly into the arteries of the heart whilst taking moving x-ray pictures such that you can watch the flow of blood down the coronary arteries. This is repeated at several different angles and repeated for all of the coronary arteries so that the arteries can be looked at from multiple different angles. The dye is injected into the coronary arteries directly using a long narrow tube called a catheter. This catheter is introduced either through the artery in the groin or through the artery in the elbow or wrist. The catheter is carefully guided to the heat where is it positioned at the beginning of each of the coronary arteries. 

What is involved with an angiogram? 

- Angiograms are only performed in certain hospitals but are normally performed as day-stay cases without the need for overnight hospitalization.

- You will be admitted to hospital and further assessed by experienced nursing staff. You would normally have localised shaving of the groin region, a resting ECG and blood tests will be performed. A small intravenous cannula will be placed into the vein on the back of your hand.

- You would then be moved into the “Catheter Lab”, the sterile operating room.

- The groin area (or arm) will be cleaned with antiseptic solution and you will be covered with a sterile drape to ensure that the area that your doctor is working on remains sterile.

- Your doctor will then locate the artery in the groin and administer local anaesthetic in this area. This normally stings a little bit, perhaps like a bee sting, but should soon make this area numb.

- A needle is then inserted into the artery in the groin ( or arm) and a further intravenous cannula is placed into the artery to give access to the coronary catheter. Once the catheter is in the artery you should not feel any discomfort or sensation.

- A catheter is then advanced through the groin up to the heart and carefully placed in the mouth of each coronary artery. Whilst holding your breath approximately 5-10mls of contrast dye will be injected into the artery whilst taking x-ray pictures. This will be repeated in several different angles.

- The shape of the catheter will be changed on several occasions to take a picture of the other coronary arteries. It is also possible than an internal picture of the heart will be performed. Whilst this is not uncomfortable, it may give a warm sensation flowing throughout the body.

- At the end of the procedure, the catheter is removed but the sheath in the artery of the groin will still be in place, which also needs to be removed. This will either be removed with sealing the small hole in the artery by placing a small collagen plug, or by applying prolonged pressure so that the body heals the hole itself by forming its own clot.

- Either way, you will then be required to lie flat and in bed for a period of one to four hours to allow the groin to heal and minimize the chance of bleeding from the needles site.

- You will then be allowed to mobilize for a period of one to two hours under supervision, and if the groin remains stable you will then be allowed to be discharged.  

How long does an Angiogram take?

Although the actual procedure itself is relatively quick, the time does vary depending on ease of access and how difficult the case is. This time can vary from ten minutes to forty five minutes for an average case. However, we do advise patients to devote the whole day to the procedure as there is always some preparation and several hours of lying and sitting to allow the groin to heal to minimize the chance of bruising and bleeding.  

Is there any preparation for an Angiogram?

Your doctor will discuss the angiogram with you prior to admitting you to hospital. You will be required to fast from midnight the night before the procedure. You should tell your doctor whether you have any allergies, particularly to iodide based substances. Your doctor will have discussed with you your medications, including diabetic medications such as insulin. He will give you appropriate instructions about these type of medications but most medications should be continued and brought to the hospital with you on the day of the procedure. You will not be allowed to drive home after your angiogram and therefore arrangements should be made for someone to drive you home and escort you. If you take Warfarin you must inform your doctor. 

Are there any precautions after the Angiogram?

You can not drive home after an Angiogram. In most situations patients can return to normal activity the following day. We do advise patients, however, not to do any heavy lifting and to avoid straining for 24 hours as this does put pressure on the groin, increasing the chance of bruising re-bleeding. You should arrange to have someone in the house with you the first night after an Angiogram in case there is further bleeding from the groin. 

What are the risks of having an Angiogram?

On the whole coronary angiography is an extremely safe procedure, but because it is invasive there are potential risks.

- The commonest risk involves the groin with approximately 5% chance of significant bruising and having further bleeding from the groin after the test has finished. This is the main reason we keep patients in hospital for several hours and the experienced staff are trained to deal with this. It is very common for patients to have a significant bruise without any swelling and this will subside over a couple of weeks.

- The more serious risks during angiography in total occur in less than 1 in a 1000 cases. These risks would include having an allergic reaction to the dye, a disturbance of the heart rhythm, a fainting episode, a transient heart attack or a transient stroke. These possibilities are extremely unlikely and the staff and your doctor will take very precaution to avoid their occurrence. Although very unusual, there are reported cases of death during angiography.  

How accurate is an Angiogram?

For narrowing of the arteries coronary angiography remains the Gold Standard and is close to 100% accurate. 

What to expect after an Angiogram?

After angiography the results will be available to you immediately and normally your doctor will discuss these with you. The results of your angiogram will dictate possible outcomes. Whilst in hospital possible results would include a normal angiogram or minor narrowing in some of the arteries which does not dictate any need for intervention at that stage.  If significant narrowing’s are detected, usually this information is relayed to your doctor who will decide whether appropriate management is required, such are coronary artery stenting. Under rare circumstances, such severe narrowing’s are found in critical coronary arteries, that the doctor performing your angiogram may feel it is safer to keep you in hospital to either offer you stenting or urgent bypass surgery.