Types of stroke (definition, symptoms, causes and severity)

To this day, the word stroke is not unknown to the majority of the population. Cerebrovascular accidents or ictus are one of the main causes of death in the world, being in our country the second largest cause of death and the first in women over 75 years of age, as well as the leading cause of disability.

This phenomenon is due to an obstruction in the circulatory system in the brain, which causes death by suffocation of part of the brain. But not all strokes occur in the same way or from the same causes. In order to better understand this phenomenon, in this article we are going to analyze the different types of stroke that exist.

Stroke or cerebrovascular accident

By stroke or cerebrovascular accident we understand the death or alteration of brain tissue produced by obstructions or ruptures of the blood vessels responsible for irrigating them. The effects of these phenomena will vary greatly depending on the area that is affected, being able to cause from death to the loss of skills such as sight or movement on the part of the Body.

In general, the factors that lead to the onset of stroke are silent (You have to be especially careful with hypertension and diabetes, as well as the consumption of tobacco and alcohol) and the person who suffers from it does not usually realize the possibility of suffering from it.

In addition, a large part of the population does not know the main warning signs that could be warning of the existence of a cerebrovascular accident. There are three very relevant symptoms whose joint presence is usually linked to suffering from a stroke: the existence of hemiparesis or sudden paralysis of one side of the face (it is common to see it in the smile), the existence of sudden speech disorders (uncoordinated, illogical, unintelligible or bizarre speech) and weakness or hypotonia (even paralysis) of one or more limbs of hemibody.

It is essential to go to medical services as quickly as possible, since early care will prevent or reduce the death of brain tissue. Even if it does not cause the death of the patient, it is likely that they generate some type of disability (although in many cases the lost skills could be recovered).

Types of stroke

As we have said, not all strokes have the same characteristics, occur in the same way, or are due to the same causes. That is why we have different classifications regarding the types of stroke.

As usual, The existence of two large groups has been considered, within which we can find different typologies.

1. Hemorrhagic stroke

Hemorrhagic stroke or cerebral hemorrhage is that type of cerebrovascular accident that occurs before the rupture of one or more blood vessels, flooding the brain tissue with blood and causing it to suffocate. And to this damage must be added the pressure that the accumulation of blood inside the skull can cause. They can not only occur in the brain but also at the level of the meninges and within the cerebral ventricles.

Different types of hemorrhagic strokes can be found, which can be caused in different circumstances.

1.1. Head injury stroke

A head injury can in turn cause a stroke in the form of a brain hemorrhage, by breaking the blood vessels of the brain.

1.2. Aneurysm stroke

Another common cause of cerebral hemorrhage is the presence of aneurysms, localized widening of the blood vessels that are generated due to the weakness of the blood vessels. These are protrusions filled with blood that, since they have a weakened wall, are very easy to break under the pressure exerted by the blood flow.

1.3. Stroke due to AVM and other malformations

There are different disorders and syndromes of genetic origin that cause the blood vessels of the brain to not develop correctly or are very fragile, as occurs in arteriovenous malformation syndrome, so it can be easy for them to break.

2. Ischemic stroke

Also called a cerebral infarction, ischemic stroke occurs when one of the arteries in the brain becomes blocked, causing interrupts blood flow to part of the brain. This means that the brain tissue does not have the oxygen and nutrients necessary to survive, dying in a short time. In general, when we talk about stroke we usually refer to those of this type, being the most frequent of the large types.

Within ischemic strokes we can find several types.

2.1. Stroke due to cerebral embolism

In embolism, the element that causes the artery to be blocked comes from outside the nervous system, traveled through the blood to reach said system and cause ischemia if it is larger than the blood vessel through which it passes. It is usually a blood clot that breaks loose from its place of origin.

2.2. Stroke due to cerebral or atherothrombotic thrombosis

In this type of ischemic stroke the blockage occurs within the blood vessels of the brain itself. It is usually common in people with arteriosclerosis.

2.3. Lacunar or small vessel stroke

Lacunar stroke is a subtype of ischemic stroke in which the blocked blood vessel is an arteriole, part of the branches of the arteries that reach the different points of the brain. The amount of tissue that dies is usually small, but it can also have serious effects depending on the area in which it occurs. Likewise, it is also possible that no type of symptoms are manifested, and the lesion may remain silent.

2.4. Transient ischemic attack

This type of ischemic stroke occurs when one of the blood vessels is blocked They irrigate a part of the brain, but the system itself is able to overcome it so that symptoms occur in a short period of time that can last up to 24 hours.

However, although it resolves on its own, it is usually indicative of the possibility of developing a further stroke. severe and permanent, being necessary that the affected person carry out prevention strategies and controls of their state of Health. It would be similar to the relationship between angina pectoris and a heart attack.

2.5. Hemodynamic stroke

It is a type of stroke in which there is a decrease in the level of blood pressure that causes the blood to not reach with enough force to properly irrigate the entire brain. Although there may not be an obstruction as such, it is considered one of ischemic strokes.

Bibliographic references:

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