Answer: Tissue plasminogen activator is a medicine that is used to treat ischemic stroke.
Stroke is a severe, life-threatening condition that results from a lack of blood flow to the brain. Because the neurons in the brain are very dependent on oxygen and nutrient flow, just a few minutes of blood deprivation can cause permanent damage.
There are two major types of strokes. An ischemic stroke is when a blood clot travels through the blood vessels in the brain and gets lodged in a narrow capillary. At this time, it is important to destroy the blood clot as soon as possible in order to maximize blood flow and prevent damage.
Tissue plasminogen activator (tPA) is a protein that aids in the process of clot destruction. While tPA is an endogenous substance, it can be delivered artificially by medical professionals. tPA deliver is most effective if given within 6 hours. When given within this time window, the odds of survival and complete independence after stroke are increased. However, evidence is scarce demonstrating efficiency of tPA when given after this time window.
It is also important to differentiate between the two different types of stroke, since tPA is actually contraindicated in hemorrhagic stroke. This type of stroke is caused by a ruptured blood vessel, possibly due to an arteriovenous malformation. If tPA is delivered in this case, it becomes more difficult for the blood to stop spilling, making tPA treatment more dangerous.