Aneurysms and AVMs
Hemorrhagic strokes are frequently caused by the bursting of an aneurysm (an abnormal "bulging" of a blood vessel in the brain) or an arteriovenous malformation (AVM), a cluster of abnormal blood vessels. In the case of an aneurysm, the weak spot in the vessel wall can be stretched out over the years, often by high blood pressure, which ultimately causes it to rupture. While aneurysms may not cause any symptoms until they burst (sometimes causing people to liken them to "time bombs" in the brain), AVMs may have many associated symptoms, including seizures, progressive neurologic problems and severe headaches that are unresponsive even to strong medications.
Until recently, some aneurysms and AVMs were virtually impossible to treat without high risk to the patient. New diagnostic and surgical advances have made it possible to treat these important causes of stroke and offer patients the likelihood of a cure.
There are many positive steps that you can take now to reduce your risk of stroke. The most common risk factors for stroke are listed below. These include some conditions that can be changed by lifestyle modification or medical treatment, and some, such as hereditary factors, that cannot be changed.