CNI Stroke Program
Stroke Diagnosis & Treatment
On a national level, only about 5% of stroke patients receive intravenous t-PA, a clot-busting drug, for acute ischemic stroke (caused by a blood clot). This is primarily related to missing the critical 3-hour window of opportunity for treatment.
The CNI Stroke Program works closely with Swedish Medical Center, where 22% of stroke patients are treated with IV t-PA. Our efficient Stroke Alert system provides coordinated, aggressive treatment for stroke patients. Our physicians are experienced in identifying the safe administration of t-PA, a complex treatment. Administered through an IV or vein/systemically, t-PA is currently the only FDA-approved treatment for stroke.
Blood Tests - Typically included as part of the general exam, the blood tests will help your physician identify any disorders of the blood and will provide levels of cholesterol and blood sugar to test for diabetes as well as other risk factors. Based on findings, your physician may determine that more specialized blood tests are required.
Computed Tomography (CT) Scan - One of the most common tests given to patients for stroke or stroke risk, the CT scan gives your physician a picture of the anatomy of your brain, helping to identify areas lacking adequate blood flow. For patients who are having a stroke, a CT scan is used to determine if it is caused by a blood clot, a ruptured blood vessel or aneurysm. Specifically, a CTA is used to scan the blood vessels, while a CT perfusion is used to scan how blood supplies the brain tissues. Patients who may be pregnant should discuss all potential risks with their doctors before proceeding with a CT scan. The CT scan administered at Swedish may include a CT, CTA and perfusion study because of the speed, 5 –10 minutes, required to complete the entire test. An MRI, while more specific than the CT, takes much longer to do and requires the patient to hold very still for an extended period of time—up to 30 minutes—so it is not used as the initial screening test.
Magnetic Resonance Imaging (MRI) - An MRI is a more sensitive scan that can help your physician identify areas in your brain lacking adequate blood flow—at earlier stages. Because of the strong magnetic field and radio frequencies, people who have a heart pacemaker or any kind of metallic implant in their body shouldn’t have an MRI unless their physician approves the procedure. Patients will not be able to wear anything metallic during this procedure. The MRI test, while more specific than the CT, takes much longer to do and requires the patient to hold very still for an extended period of time—up to 30 minutes—so it is not used as the initial screening test.
Angiography - A test where a catheter is threaded through an artery in the groin and up into the brain. X-rays and dye are used to see abnormalities in the vessels.
CT Angiogram - The CT Angiogram, “angiography,” is a minimally invasive medical test that helps physicians diagnose and treat medical conditions. Angiography uses one of three imaging technologies and, in some cases, a contrast material to produce pictures of major blood vessels throughout the body. Angiography is performed using x-rays with catheters, computed tomography (CT), and magnetic resonance imaging (MRI). CT imaging uses special x-ray equipment to produce multiple images and a computer to join them together in multidimensional views. In CT angiography (CTA), computed tomography using a contrast material produces detailed images of both blood vessels and tissues.
Non-invasive Vascular Assessment (NIVA)
Your physician may request a NIVA exam, if you have had symptoms suggestive of a TIA. The NIVA exam uses advanced imaging techniques to painlessly evaluate the circulatory system without the use of needles, dye or radiation. A carotid NIVA exam evaluates the carotid arteries in your neck for narrowing or obstruction. A venous NIVA exam is used to look for blood clots in your veins. This is performed with ultrasound, a non-invasive imaging technique that uses sound waves to look inside your veins and blood vessels. The reflected sound waves produce both auditory and visual signals. The patterns tell the doctor how much atherosclerotic obstruction exists in the arteries and, therefore, how compromised is the blood flow to the brain.
Echocardiogram - This test is done to check for any abnormalities of the heart, such as abnormal heart rhythms, coronary artery disease or previous heart attacks. An echocardiogram uses ultrasound waves, delivered at the chest wall, to examine the heart. It is a safe and painless procedure that helps doctors diagnose a variety of heart problems.
Transesophageal Echocardiogram (TEE) - A type echocardiogram is done from inside the esophagus (the tube leading from the mouth to the stomach). Because the esophagus lies just behind the heart, the TEE provides clearer images of the heart than a standard echocardiogram. The TEE provides better images and is generally performed when doctors want to examine hard-to-see structures of the heart.
An acute stroke (brain attack) is very similar to a heart attack in that a blood clot suddenly blocks a blood vessel feeding the brain. If that blood clot can be quickly dissolved, the effects of the stroke often can be partially or totally relieved, and blood flow is restored to that part of the brain. Just as treating heart attacks rapidly leads to positive outcomes, an effective therapy for treating acute stroke with clot-busting medicines is now available.
The faster a blood clot is dissolved in the brain, the better. If a stroke patient arrives at the emergency room when symptoms occur, the emergency room doctor and neurologist can administer t-PA intravenously within the first three hours of symptoms. However, if three hours of symptoms has elapsed, an x-ray guided angiogram and catheter-directed administration of t-PA often can be performed. This catheter-directed treatment has been shown to work well up to six hours after stroke symptoms occur. After six hours the brain often has suffered irreversible damage and these clot-buster drugs are not recommended.
Intravenous Clot-Busting Therapy - By dissolving blood clots to the brain quickly, the quality of life in stroke patients is improved medicine, Intravenous administration of tissue plasminogen activator (t-PA), has its best effect when given intravenously within the first three hours of stroke symptoms
Catheter-Directed Therapy - After three hours of symptoms has elapsed from onset of stroke, an x-ray guided angiogram and may be advanced from the groin directly into the brain and the offending blood clot. Using x-ray guidance, a physician guides a thin, hollow plastic tube from the groin directly into the blood clot to dissolve it by infusing only a small amount of the clot-busting drug. t-PA has been shown effective when administered up to six hours after stroke symptoms have begun and often reverses the effects of the stroke. After six hours the brain often has suffered irreversible damage and these clot-dissolving drugs are not recommended.