This Is Your Brain On Stroke
May Is Stroke Awareness Month
Part 2 of the Einstein Exponent Stroke Series with Dr. George Newman, Chairman, Department of Neurosensory Sciences, Einstein Healthcare Network
“If you are having symptoms of a stroke, what kind it is doesn’t matter,” says Dr. George Newman, chairman of the department of neurosensory sciences at Einstein Healthcare Network. “Get to a hospital.”
Those warning signs compose the acronym FAST: face, arm, speech, time. Face drooping, arm weakness and speech difficulty mean it is time to call 911.
What happens during a stroke? “It is an injury to the brain caused by a loss of blood supply,” Newman explains. There are three kinds of stroke: ischemic, transient ischemic attack (TIA) and hemorrhagic. All present with the same symptoms.
More than 80 percent of strokes are ischemic. They occur when there is blockage in a blood vessel that supplies the brain, Newman explains. More than 25 percent of blockages are caused by atherosclerosis of the arteries — like the carotid — that transmit blood to the brain. Nearly as many strokes result because of a clot traveling from the heart to the brain.
“The brain is not very big, but it is very active metabolically,” Newman says. “About 20 percent of all the blood leaving the heart goes to the brain, so a clot will travel there quickly. Also, the brain has very little reserve of ATP, the currency that makes it run, or of oxygen or sugar – and it can’t use fats. Basically, the brain is a big, expensive computer that absorbs a lot of the body’s resources — and it is constantly running. When something goes wrong, it goes wrong fast and interrupts the entire system.”
TIA is a transient ischemic attack. Basically, it is a blockage that clears on its own before any permanent damage to the brain occurs. “This is a golden moment,” Newman says, “because the patient has been given a warning without the lasting effects of a stroke. Smart patients will heed the warning and get their risk factors under control to avoid a future stroke.”
Hemorrhagic strokes occur when a blood vessel ruptures and bleeds into the brain, Newman explains. The blood pushes against brain tissue, compressing it and causing the stroke. There are two kinds of hemorrhagic strokes: intracerebral, which happen inside the brain, and subarachnoid, which happen on the brain’s outer surface. Cerebral aneurysms — in which a weak vessel balloons with blood and pushes against brain tissue — are among the causes of hemorrhagic strokes.
What causes the weakening of these vessels and the clogging of these arteries? The American Stroke Association says that high blood pressure is the leading cause of stroke. High cholesterol is another culprit. It clogs arteries that, when blocked, can deprive the brain of blood and result in stroke. Smoking, Newman says, is a huge contributor to strokes. “In fact, smoking is a much bigger risk factor for stroke than for heart attack,” Newman says. “Cigarette smoking accelerates atherosclerosis and makes the blood much more likely to clot.”
Diet, exercise and quitting smoking are three lifestyle factors that people can change to lower their risk of stroke. Newman recommends the Mediterranean diet, which is high in fruits, vegetables and healthy fats and low in cholesterol. “I also want people of all ages to get three hours of aerobic exercise every week,” he says. “That increases blood flow, reduces inflammation and lowers blood pressure. I don’t care if you walk, swim or do Zumba, but I want aerobic activity with the heart rate elevated. I want a good shvitz!”
Other methods for reducing the risk for stroke require the help of doctor. “There are blood pressure, cholesterol and blood sugar medications that we prescribe,” Newman says. “But even if I put you on those, I still want you to adopt those lifestyle changes. Diet and exercise are difficult but not as difficult as recovering from a stroke. We help many, many people recover. But I also want to help many, many people prevent them from happening.”