Everyone knows this entity. Everyone, if they think about it, fears this entity. Today, we will talk a little about stroke, define it, describe its various presentations, and talk about diagnosis and prevention.
The Difference in Strokes, TIAs and RINDs
A true stroke means there is some dead brain. Most commonly, the brain dies because of sudden lack of blood supply. When oxygen and nutrients are taken away from brain tissue, that tissue will die. Unfortunately, small amounts of brain death can result in severe mental and motor malfunction, depending on the location of the insult. This damage is permanent.
A “mini-stroke” is a misnomer. This is a term often used to describe a set of symptoms that comes on like a stroke, but then gets better within 24 hours. The true name for this type of event is a “TIA”. This stands for “transient ischemic attack” and is telling you that transiently (less than 24 hours) there were stroke symptoms, but they resolved within 24 hours. Ischemia means lack of blood.
The next step up in severity from a TIA describes brain damage that lasts longer than 24 hours, but then reverses itself back to normal. This type of injury is called a “RIND” or “reversible ischemic neurologic deficit”. This occurs when the symptoms are more severe than a TIA. These symptoms take longer than 24 hours to resolve, but they are reversible. Stroke is the worse and stands for permanent damage-cell death as opposed to cellular insult.
Causes of Strokes
The most common cause of stroke in this country remains blockage or partial blockage of the carotid artery, the main blood vessel leading to the brain. The most common scenario is frightening, in that there is usually no warning. The blockage (atherosclerosis or plaque) builds up over time, without the patient even knowing it. Suddenly, without warning, there is an event.
Most commonly, a piece of plaque is dislodged and it enters the blood stream, like a wood chip floating down a river. It enters the brain and continues to float into the interior of the brain. As it moves on, the size of the blood vessels gets smaller and smaller.
At some point the diameter of the vessel matches the diameter of the plaque. At this point the plaque is stopped, blocking the vessel. The part of brain that is supplied by this vessel suddenly has its source of oxygen and nutrients cut off. Depending on the size of the vessel blocked and the completeness of the blockage the result is one of the 3 scenarios described above: TIA, RIND, or stroke.
In Part 2 of our discussion, we'll talk about the discovery of this silent problem and prevention of strokes.
Dr. Robert W. Ruess, MD, of Five Star Vein Institute, is a Board Certified Cardiovascular, Thoracic Surgeon and is also certified by the American Board of Phlebology. Call today to schedule a free vein screening at Five Star Vein Institute.