This leaflet explains the procedure of embolisation of varices, its benefits, its risks and alternative treatments that will have been considered by the clinical team managing your care. It is aims to provide information for patient’s who are being considered for the procedure and also for their carers/relatives.
What are varices?
Varices are distended veins that appear in the lining of the oesophagus (gullet or food pipe) and stomach.
They commonly occur in patients who have liver scarring (cirrhosis). Liver cirrhosis causes a restriction in blood flow through the liver. This, in turn, causes an increase in the blood pressure in the vein that takes blood into the liver (the portal vein). Varices are ‘bypass’ channels which the body forms to allow blood to get from the portal vein back to the heart, when it cannot freely pass through the liver.
Varices can also occur in patients who have a normal liver but who have developed a blood clot in their portal vein. The blockage caused by the clot prevents blood from passing normally into the liver. The body then diverts blood through alternative veins, which form varices.
Because varices are veins that are larger and are under higher pressure than they would normally be, they are at risk of bleeding.
How are varices normally treated?
Varices are normally treated with endoscopy. Endoscopy is a procedure where a camera is placed through the mouth, down the oesophagus (gullet) and into the stomach.
Special equipment can then be passed through the endoscope to block the blood flow in the varices and prevent bleeding. This is done by either placing elastic bands over the varices (variceal banding/ligation) or by injecting medicines to cause the blood to clot within the blood vessel. However, sometimes, repeated treatment can lead to scarring and make further endoscopic treatment very difficult. The location of varices can also make endoscopic treatment more difficult, especially if the varices are found in some parts of the stomach.
In patients where endoscopic treatment is becoming difficult or no longer possible, the next step would be to consider a procedure called a TIPS (transjugular intrahepatic portosystemic shunt). This creates an artificial bypass around the liver, to reduce the pressure in the portal vein, which then stops varices from bleeding.
However, there are some instances where a patient may not be able to have a TIPS procedure, either because of clinical reasons or because a TIPS may not be technically possible.
What if my varices cannot be treated by endoscopy or a TIPS?
Alternative, less conventional, treatments are available for treating varices when endoscopy is no longer possible and TIPS is not ideal or feasible. These involve a procedure called embolisation.
Embolisation is a procedure to occlude (block off) blood vessels from the inside to prevent them bleeding. The procedure is performed by an experienced interventional radiologist, a specialist who performs image-guided surgery, using a tiny incision in the skin to access the blood vessels for treatment.
In the case of varices, embolisation is performed using a liquid glue (similar to superglue) which is injected into the varices and causes a blockage of blood flow as the glue sets inside the vein. The injection is performed under X-ray guidance to check that the glue flows into and blocks the blood vessel (varix).
How is embolisation of varices performed?
You will have an initial CT scan to work out which normal veins the varices connect to and how these can be accessed. The interventional radiologist will review the scan and work out how best to access the veins connecting to the varices. This could be through a vein in your liver, spleen, neck or groin, or a combination of these.
The procedure is normally performed under local anaesthesia. The skin at the site to be accessed is numbed and a very fine tube (catheter) is placed in the vein using ultrasound. The tube is then passed to the site of the varices. X-ray dye (contrast) is injected to assess how fast blood flows through the varices and where the blood flows to.
If the blood flow is sufficiently slow, embolisation with glue alone can be performed.
If the blood flow is fast, it initially needs to be slowed down to prevent the glue passing straight through the varices. This is achieved by placing a device in the vein to partially block the flow. A variety of devices are used for this, including temporary balloons to slow down the flow and more permanent metal coils or plugs to partially block the flow. Once the flow has been slowed sufficiently, the glue can then be injected into the varices.
What are the risks of embolisation?
The main risk of embolisation with glue results from passage of glue into normal veins adjacent to the injection site, causing unintentional blockage of these veins. It is difficult to predict what the consequence of this could be as it would be dependent on which veins blocked. This could range from no, or minimal, consequence if minor veins became blocked, through to increase in portal hypertension if major branches of the portal vein became blocked.
There is also a risk of the glue passing through the varices before it solidifies. If this occurs, the glue would pass through into the lungs causing a pulmonary embolus, similar to a blood clot in the leg (DVT) passing to the lung. Often these ‘glue’ emboli are very small in size and quantity, and do not cause any significant clinical problem. However, there is a small risk of causing breathlessness or chest pain if a larger quantity of glue emboli passed into the lungs. It may require treatment with oxygen.
When a balloon is used to temporarily slow the blood flow to allow glue embolisation, there is a small risk of the balloon bursting part way through the procedure.
This can result in the glue flowing away from the injection site, possibly into the lungs. This may cause shortness of breath or chest pain. It may require treatment with oxygen.
In rare instances, there have been a very few cases of glue passing through small connections in the heart (shunts) and into arteries supplying the brain. Although this complication is rare, this could result in a stroke and a risk of death.
Embolisation does not alter or the correct the portal hypertension. It only treats the varices (the consequences of high blood pressure in the portal vein) in a similar manner, but as an alternative, to endoscopy. Because the varices are bypass channels, blocking them can result in a further increase in portal hypertension. This increase in portal hypertension may present as new varices in a different location, or development of, or increase in, fluid collecting in the abdomen (ascites).
Embolisation of varices can also result in sluggish flow in the portal vein or its main branches, with subsequent thrombosis (clotting) of the portal vein and increase in portal hypertension. This could, again, lead to varices forming elsewhere and development of ascites.
How effective is embolisation at treating varices?
Embolisation is an effective treatment for preventing bleeding from varices in the short and medium term. There is currently very little information about the longer-term outcome following embolisation of varices, so the longer-term effectiveness of the procedure remains uncertain. However, because it does not correct the underlying portal hypertension, there is a risk of recurrent varices forming in the future.
I have read this leaflet and have questions,
what happens next?
Embolisation of varices is generally a procedure that is tailored to an individual, based on the location, size and distribution of their varices.
The doctors looking after you will arrange to have a conversation with you about the procedure and answer any questions you may have.
If you are in hospital, they will come and see you on the ward.
If you are an outpatient, they will arrange an appointment to discuss the procedure in clinic.