What is the difference between ischemia and embolism

There are usually no warning signs and bleeding can be severe enough to cause coma or death. Subarachnoid hemorrhage results when bleeding occurs between the brain and the membrane that covers the brain meninges in the subarachnoid space. This type of hemorrhage is often due to an aneurysm or an arteriovenous malformation AVM.

It can also be caused by trauma. An aneurysm is a weakened, ballooned area on an artery wall and has a risk for rupturing. Aneurysms may be congenital present at birth , or may develop later in life due to such factors as high blood pressure or atherosclerosis. An AVM is a congenital disorder that consists of a disorderly tangled web of arteries and veins. The cause of AVM is unknown, but it is sometimes genetic or part of certain syndromes.

Recurrent strokes occur in about 1 in 4 people who have had a stroke within 5 years after a first stroke. The risk is greatest right after a stroke and decreases over time. The likelihood of severe disability and death increases with each recurrent stroke. At 88 years old, Mary is an avid Scrabble player and church choir singer.

She knows her way around the iPad. Health Home Conditions and Diseases Stroke. Strokes can be classified into 2 main categories: Ischemic strokes. What is an ischemic stroke? Ischemic strokes are further divided into 2 groups: Thrombotic strokes. Thrombotic stroke Thrombotic strokes are strokes caused by a thrombus blood clot that develops in the arteries supplying blood to the brain. Embolic stroke Embolic strokes are usually caused by a blood clot that forms elsewhere in the body embolus and travels through the bloodstream to the brain.

There are two kinds of stroke due to ruptured blood vessels:. In both types of hemorrhagic stroke, blood flow is disrupted to part of the brain. Victims of hemorrhagic strokes are often younger and the fatality rate is higher than for ischemic stroke.

Overall prognosis is also poorer for those who have hemorrhagic strokes. About 10 percent of strokes follow incidents called transient ischemic attacks, or TIAs. TIAs may occur days, weeks or months before the onset of a stroke. The symptoms of a TIA are like the warning signs of a stroke, but they usually last only a few minutes.

Blood clots are clumps that occur when blood hardens from a liquid to a solid. A blood clot that forms inside one of your veins or arteries is called a thrombus. A thrombus may also form in your heart. A thrombus that breaks loose and travels from one location in the body to another is called an embolus. A thrombus or embolus can partly or completely block the flow of blood in a blood vessel. A blockage in an artery may prevent oxygen from reaching the tissues in that area. This is called ischemia.

If ischemia is not treated promptly, it can lead to tissue damage or death. A blockage in the vein will often cause fluid buildup and swelling. Situations in which a blood clot is more likely to form in veins include: Being on long-term bed rest Sitting for long periods, such as in a plane or car During and after pregnancy Taking birth control pills or estrogen hormones especially in women who smoke Long-term use of an intravenous catheter After surgery Blood clots are also more likely to form after an injury.