Arteriovenous Malformations (AVMs)September 13, 2019
The High Court case concerning Tafida Raqeeb has been widely commented upon recently in the media. Tafida, aged 5, sadly suffered a serious deterioration after an Arteriovenous Malformation (AVM) ruptured in her brain in February, causing a serious bleed. She suffered a brain injury and has required life support ever since. Tafida’s parents have brought a High Court case seeking permission to transfer Tafida to Italy for treatment against the advice of her treating doctors here in the UK. The case is ongoing and a decision is expected shortly.
What is an AVM?
Little is known about the cause of this rare condition.
An AVM is where the arteries and veins grow tangled together rather than forming a network. They can be big or small and are able to form in several parts of the body including the spinal cord and the brain, as in Tafida’s case. They may be present in both children and adults.
AVMs are thought to develop before birth or shortly afterwards and are often present for a very long time without symptoms before they are diagnosed.
These can cause serious medical problems as the blood vessels sometimes expand, causing them to burst and bleed, disrupting the flow of blood to the brain.
What are the symptoms of an AVM?
An AVM can cause very few symptoms for years. Some symptoms of brain AVM include:
- Ringing in the ears (pulsatile tinnitus).
- Visual problems
- Memory issues.
However, the symptoms above are largely non-specific and could be attributed to a number of other medical conditions.
If an AVM bleeds, this can produce immediate symptoms such as a sudden intense headache, nausea, vomiting and reduced consciousness. Bleeding can also be diagnosed with scans or other tests.
It is important therefore that symptoms are properly investigated as the complications of an AVM may be life-threatening.
Treatment for AVM
Although bleeding from an untreated AVM has the potential to cause considerable problems, treatment for AVM itself can also carry its own risks.
There has to be a careful balancing exercise between the risks and benefits of treatment against the risks of the untreated clinical course.
For AVMs in the brain, there are three main methods of treatment:
- Neurosurgery – this is where the AVM is surgically operated on and removed. The risks of such surgery include bleeding, stroke and seizures.
- Embolisation – this is where the blood vessels are treated with a substance to reduce the blood flow through the enlarged blood vessels and reduce the risk of bleeding. The advantage of this procedure is that it is minimally invasive, although there may be risks of infection, damage to the blood vessels or other risks including stroke as above.
- Stereotactic radiosurgery – this is where a high treatment dose of radiation can be used to treat smaller AVMs
Unfortunately, some AVMs may not be treatable if the risks of treatment are considered to be too large to outweigh the potential benefits. For example, if an AVM is too large or is in a difficult position in the brain, it may be too risky to treat it as the potential damage to the brain could cause significant disability.
Complications of an AVM
An NHS study on adults with the condition, estimates that the risk of AVM bleeding where it is untreated is approximately 2% per year, but the risk of recurrent bleeding (after a first bleed) could be as high as up to 18%.
Bleeding can significantly increase the risks of a stroke. It is important therefore to consider treatment carefully as this has potentially life-changing implications.
As sadly in Tafida’s case, an AVM can rupture at any time, causing devastating consequences.
Investigations should be carried out appropriately and promptly where there may be symptoms or suspicions of an AVM. If left untreated, the risks to a person’s health could be significant.
It is important to reach a diagnosis, discuss the risks and treatment options with a medical professional at the earliest opportunity.
Deepti Patel is a senior solicitor in the Adult Brain Injury team at Bolt Burdon Kemp. If you feel you may have a claim or are enquiring on behalf of a loved one, you can contact Deepti free of charge and in confidence at firstname.lastname@example.org. Alternatively, complete this form and one of the solicitors in the Adult Brain Injury team will contact you. Find out more about the Adult Brain Injury team.