Some strokes are due to bleeding in or around the brain. These are called haemorrhagic strokes. Although they are not as common as ischaemic strokes (caused by a blockage), haemorrhagic strokes can be more serious.
A haemorrhagic stroke can happen when an artery inside your brain bursts causing bleeding within your brain. This is known as an intracerebral haemorrhage.
It can also happen because of bleeding on the surface of your brain. Your brain sits inside a cushion of membranes that protect it from your skull.
Between the layers of membrane is a space, which is filled with fluid. If blood vessels near the surface of the brain burst, blood can leak into this space. This known as a subarachnoid haemorrhage.
Some of the things that can cause bleeding in and around your brain include:
- High blood pressure, which is a contributing factor in around half of all strokes.
- Cerebral amyloid angiopathy is a condition where a protein called amyloid builds up inside the blood vessels in the brain. This causes damage and makes your blood vessels more likely to tear. This condition is more common among older people.
- An aneurysm is a weak spot on an artery, where the walls have become thin and weak. This means that they can sometimes burst, especially if you have high blood pressure. Some aneurysms are present from birth, but some things can make you more likely to develop one, including smoking, high blood pressure, and having a family history of aneurysm.
- Anticoagulant medication helps to prevent blood clots forming. If you have an irregular heartbeat (known as atrial fibrillation) it’s likely that you will be given this type of medication to help reduce your risk of stroke. When you are on anticoagulant treatment you will be carefully monitored to reduce the chance of bleeding.
- Illegal drugs, such as cocaine, can irritate blood vessel walls making them weaker and more likely to rupture.
A stroke is a medical emergency and if you have any stroke symptoms you need to call 999 immediately.
The quicker your stroke is diagnosed and treated, the better your recovery will be.
A brain scan can show what type of stroke you have had. A computed tomography (CT) scan or a magnetic resonance imaging (MRI) scan help doctors find out whether a stroke was caused by bleeding or by a blockage.
If you have a subarachnoid haemorrhage then doctors may carry out a lumbar puncture. To do this they remove a small amount of the fluid that sits around your brain and spinal cord, to see if any blood has leaked into it.
If you have a haemorrhagic stroke you may need surgery to stop the bleeding, remove blood or relieve any pressure that has built up around your brain.
This is usually done with an operation called a craniotomy. This is when a surgeon cuts away a small piece of your skull so that he or she can get to your brain and the cause of the bleeding.
If your stroke was caused by a burst aneurysm, an operation may be needed to seal it and stop it bleeding again.
You may be given medication to lower your blood pressure, or if your bleed was caused by anticoagulant medication, you will usually be given another drug to reverse the effects as soon as possible.