What is cardiac catheterisation?
This is a procedure to investigate the coronary arteries. The coronary arteries are vessels which leave the main blood vessel (aorta) and run along the surface of the heart supplying the heart muscle with blood. They can become lined/furred with cholesterol plaque (atherosclerosis) over time.
Most patients who are due for heart valve surgery will have a coronary angiogram prior to their surgery. This is because if there are narrowings of the heart arteries, these can be addressed during the heart valve operation with the addition of a coronary artery bypass procedure.
Cardiac catheterisation is an X-Ray dye test. The test may differ slightly according to whether you have a left heart catheterisation procedure only (coronary angiogram) or a right and left heart catheterisation procedure.
A left heart catheterisation (coronary angiogram) is usually a day-case procedure performed under local anaesthetic. You will be taken into the catheter laboratory/angiogram suite and asked to lie on a table wearing a gown. Usually your wrist (but occasionally the groin) will be cleaned and sterile drapes placed across you. Your wrist (or occasionally the groin) will be numbed with an injection of local anaesthetic and a small tube (catheter) is inserted into the artery and fed up toward the heart using X-Ray guidance. The tube is then directed towards the opening of the coronary artery. Once the tube (catheter) is in position, dye is inserted and an x-ray machine is used to make a video of the dye passing down the coronary artery. This should show narrowing in the coronary arteries. The x-ray camera will be moved around the body during the procedure to take pictures of the arteries from many different angles. You may be asked to hold your breath for a short time whilst the picture/video is being taken. Usually pictures are taken of the left coronary artery first, and then the tube swapped or moved and pictures of the right coronary artery are taken. Sometimes there is chest discomfort or you may feel unwell during the procedure; if this is the case you should tell the doctor immediately. The procedure usually takes around half an hour.
A right and left heart catheterisation is a very similar procedure to the coronary angiogram. X-Ray dye pictures of the heart arteries (coronary angiogram / left heart catheterisation) will be obtained as described above. In order to gain more information about the pressures within the heart an additional part of the procedure (right heart catheterisation) will also be performed. The doctor will introduce tubes (catheters) into the heart chambers and take direct measurements of the pressure in the heart. This is usually performed with a small tube introduced under local anaesthetic from a vein in the groin, arm or neck and takes about an hour.
What happens after the cardiac catheterisation procedure?
If the procedure is performed from the wrist, a band is applied to the wrist for several hours afterwards to prevent bleeding . If the procedure is performed from the groin, the puncture site is pressed firmly by the doctor or nurse for several minutes after the procedure (manual compression) or using a clamp device (often referred to as a Femstop). If you have the procedure from the wrist you will be able to sit up immediately and will be discharged from hospital after a few hours if you feel well. If you have the procedure carried out from the groin then you will need to lie flat for several hours after the procedure. If the procedure has been performed as a day-case then you will usually be able to go home the same day.
Are there any complications of cardiac catheterisation?
For most people cardiac catheterisation is a safe and straightforward procedure. It is however invasive and therefore can be associated with complications. These can include bleeding / bruising / damage to the blood vessels (more likely if the procedure is performed from the groin), allergy to the x-ray dye and associated kidney damage (extremely rare unless you have pre-existing kidney problems). Serious complications are rare (occurring in around 1 in 1000 people) and your doctor will discuss this with you during the consent process.