The most common administration of tPA, tissue plasminogen activator, is intravenously or through the veins to the point of injection. Since it works fairly slowly to dissolve the clot, it needs to be administered within the first three hours of the onset of the stroke.
A faster way than the intravenous method for delivering clot-busting tPA to the blockage is through intra-arterial administration. The neurovascular specialist inserts a thin, flexible catheter into an artery, usually I the groin area, and steers it up to the area of the clot then administers the tPA through the catheter. This method of administration expands the window of treatment opportunity wider than the three hours recommended for IV tPA. Patients can be treated for up to six hours when tPA is administered intra arterially to the site of the blockage because blood flow will begin almost immediately. Less tPA is needed when it is delivered directly to the clot.
Removing a clot that is causing blockage is very successful in saving lives during a stroke. Scans are used to identify the blocked artery so physicians know precisely where to find the clot. The procedure also entails "collateral circulation," allowing some blood flow to bypass the clot.
The Merci Retrieval System is a clot removal system developed by two neuroradiologists used at Main Line Health. It travels to the site of the blood clot and removes the clot. After the blood clot in the brain is located by angiography, the surgeon inserts the Merci balloon guide catheter through a small incision in the groin. Under x-ray guidance, the catheter is maneuvered up to the carotid artery in the neck and a guidewire along with a Merci microcatheter are deployed through the catheter and into the brain where they are placed just beyond the clot. The Merci Retriever, a cork-screw shaped platinum wire, is then deployed to grab and ensnare the clot. Then the balloon guide catheter is inflated to stop the blood flow forward while the clot is withdrawn and gently pulled into the catheter and out of the body. Once the balloon is deflated, blood flow is restored through the now open vessel.
Call 911 if you believe you or someone else is experiencing a medical emergency.