Classification. Hives and angioedema are described by the length of time that symptoms last. A rash and/or swelling lasting less than six weeks is called acute hives/angioedema. Episodes that last more than six weeks are described as chronic hives/angioedema. The causes and the bodyâs reactions that lead to development of hives are different in acute and chronic hives/angioedema, and so treatment is also different.
Types of Stroke. An ischemic stroke occurs if an artery that supplies oxygen-rich blood to the brain becomes blocked. Blood clots often cause the blockages that lead to ischemic strokes. The two types of ischemic stroke are thrombotic (throm-BOT-ik) and embolic (em-BOL-ik). In a thrombotic stroke, a blood clot (thrombus) forms in an artery that supplies blood to the brain. In an embolic stroke, a blood clot or other substance (such as plaque, a fatty material) travels through the bloodstream to an artery in the brain. With both types of ischemic stroke, the blood clot or plaque blocks the flow of oxygen-rich blood to a portion of the brain.
This buildup narrows the arteries, making it harder for blood to flow through. If a blood clot forms, it can stop the blood flow. This can cause a heart attack or stroke. A heart attack occurs when the blood flow to a part of the heart is blocked by a blood clot.If this clot cuts off the blood flow completely, the part of the heart muscle supplied by that artery begins to die.his buildup narrows the arteries, making it harder for blood to flow through. If a blood clot forms, it can stop the blood flow. This can cause a heart attack or stroke. A heart attack occurs when the blood flow to a part of the heart is blocked by a blood clot.