Thrombolytic (fibrinolytic) drugs help re-establish blood flow to the brain by dissolving the clots that are blocking blood flow. In June 1996, the “clot-buster” Activase® became the first acute ischemic stroke treatment to be approved by the Federal Food and Drug Administration (FDA). Activase is also known as tissue plasminogen activator (tPA). To be effective, thrombolytic therapy should be given as quickly as possible.
Tissue plasminogen activator is an enzyme found naturally in the body that converts, or activates, plasminogen into another enzyme to dissolve a blood clot. Doctors can give it to a patient by IV to speed up the dissolving of a clot. tPA should be given within three hours of the time symptoms first started. Time is an important factor associated with determining whether a patient can receive tPA.
The Merci Retrieval System was approved by the FDA in 2004 for patients who are ineligible for IV-tPA or fail to respond to IV-tPA. The system can be used for patients who are beyond the three-hour window for IV-tPA and does not have a time limit for its intended use. The system is a tiny corkscrew-shaped device that works by wrapping around the clot and trapping it. The clot is then retrieved and removed from the body.
The Penumbra System became available in 2008. It helps safely restore blood flow in or around blocked blood vessels after an ischemic stroke. The system also helps restore brain blood flow by using suction to grab blood clots in the brain. The Penumbra System is effective if used within eight hours from the time symptoms start.