Stroke
As a patient’s recovery from stroke is largely dependent on the amount of time that elapses between onset of symptoms and treatment, national efforts to educate the public center around one key message: stroke is a brain attack. Traditional treatments for ischemic stroke include tPA, a clot-busting drug given intravenously, which must be administered within three hours. In the last decade, intra-arterial (through the artery) catheter-based therapies were developed, extending the required treatment time to up to six hours. Designed to eliminate blockages in particular kinds of stroke, intra-arterial therapy is performed by inserting a catheter into the groin area and routing it through the blood vessels up to the blockage in the brain under X-ray guidance. Once the catheter is positioned, clot-busting drugs are delivered directly to the site of the blockage.
The most recent technological advancement in the treatment of stroke is the Merci® Retriever System manufactured by Concentric Medical. A tiny corkscrew-shaped device, the MERCI (Mechanical Embolus Removal in Cerebral Ischemia) Retriever is inserted through a catheter (as in other intra-arterial treatments) directly to the site of the clot. Once positioned, it is deployed to engage and ensnare the clot, pulling it back through the catheter and out of the body. Available at 120 hospital sites throughout the nation, the Merci Retriever can be used up to eight hours following symptom onset, and in some cases, even beyond this timeframe.
Ultimately, in the treatment of stroke, “time is brain.” If a patient gets to the hospital after too much time has elapsed, the damage is usually permanent and efforts to re-open the vessel may make things worse by causing a bleed in the brain.