Speed dial 911, if you suspect stroke
More than 795,000 people in the United States suffer an acute stroke every year, according to the Centers for Disease Control and Prevention (CDC). And the only Federal Drug Administration (FDA) approved medication to treat it is tPA (tissue plasminogen activator), also known as Alteplase.
The drug is used to treat ischemic strokes, which comprise about 80 percent of all strokes, according to Michael Markowski, DO, FAAN, a neurologist at Cape Cod Hospital.
“The relative benefit of receiving Alteplase is reduced disability at three months and beyond,” he said. “One out of three people will have minimal to no disability. If we treat 100 patients with Alteplase, 32 will benefit, and three will have adverse effects. We’re not helping everybody, but this is the only medication we have to treat ischemic stroke, so we want to use it when we can.”
Alteplase works by breaking up the clot that is blocking the vessel and cutting off oxygen to the brain. While it is available to all stroke patients, only 8 percent of patients in the United States receive the treatment, according to Dr. Markowski. The reason is that only about 22 percent of patients come into the emergency room within the three-hour window required for safe administration of the drug, said.
When Alteplase Is Used
“There are very strict criteria for administering the medication, and the four-and-a-half-hour time window is the most stringent of the criteria,” Dr. Markowski said.
The time for giving the medication begins when the symptoms of the stroke start, so getting to the emergency room as soon as possible is crucial.
The window is longer if you are under the age of 80. Those patients have up to four and one-half hours to receive Alteplase from the onset of symptoms. For patients over 80, Alteplase can only be given safely within 3 hours of stroke onset.
The acronym FAST is one way to remember symptoms that could indicate a stroke, according to the American Stroke Association:
- Face drooping
- Arm weakness
- Speech difficulty
- Time to call 911
“An important point to remember is that the symptoms will typically be on one side of the body,” said Dr. Markowski.
After your arrival in the emergency room, many assessments will happen very fast. You will have a neurological assessment by the emergency room physician, lab work will be drawn, a head CT scan will be done, medical history taken and another neurological exam after your CT scan.
“Our goal is to make sure there are no contraindications to giving the Alteplase and to administer it within 60 minutes of the patient’s arrival in the emergency room,” said Dr. Markowski.
Some of the criteria to receiving Alteplase include:
When you can receive Alteplase
- The stroke is an ischemic stroke and not a hemorrhagic stroke (bleeding in the brain)
- Your platelet count is normal
- Your blood pressure is not markedly elevated
- Head CT scan is normal (no bleeding)
- Meet the time and other criteria
When Alteplase cannot be given
- Your stroke is a result of bleeding in your brain (hemorrhagic stroke)
- You have uncontrolled high blood pressure (this may be treated with IV medications in the ER to bring it down so you can receive Alteplase)
- Your platelet count is low, this would increase your risk for bleeding
- You are taking blood thinners such as Warfarin or Coumadin
Other reasons you may not qualify for Alteplase is that you have stroke mimic syndrome, as similar symptoms may rarely occur with migraines or seizures. With this condition, your symptoms are like those of a stroke but may be caused by a migraine, or other neurological disease.
Another Tool to Prevent Disability
“Mechanical thrombectomy is a new tool in the toolbox of treating stroke in addition to Alteplase,” said Dr. Markowski. It is a procedure to remove blockages of larger blood vessels, and is done by a physician who is a specialist in interventional procedures in an academic hospital setting.
The physician removes the clot by going through a catheter inserted into the groin to the brain. It must be done within six to eight hours of onset of symptoms of your stroke.
The benefit of this procedure is even better than intravenous Alteplase, said Dr. Markowski.
“The absolute benefit of Alteplase is 12 percent; the addition of the mechanical thrombectomy raises it to 14 to 30 percent.”