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

This cerebrovascular disease is one of the leading causes of death in adults.

Today, the word stroke is no stranger to the majority of the population.. Strokes are one of the leading causes of death in the world, being in our country the second leading cause of death and the first in women over 75 years old, as well as the main cause of disability.

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

Stroke or cerebrovascular accident

Stroke or cerebrovascular accident is the death or alteration of brain tissue caused 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, and may cause from death to the loss of abilities such as sight or movement of part of the body.

In general, the factors that lead to the onset of stroke are usually silent (special care must be taken with hypertension and diabetes, as well as the consumption of tobacco and alcohol) and the person who suffers it is not usually aware of the possibility of suffering it.

In addition, a large part of the population is unaware of the main warning signs that could be warning of the existence of a stroke. There are three very relevant symptoms whose joint presence is usually linked to the suffering of a stroke: the existence of hemiparesis or sudden paralysis of one of the sides of the face (it is frequent to see it in the smile), the existence of sudden speech alterations (uncoordinated, illogical, unintelligible or strange speech) and weakness or hypotonia (even paralysis) of one or more extremities of one hemibody.

It is imperative to seek medical attention as soon as possible, since early attention will prevent or reduce the death of brain tissue. Even if it does not result in the death of the patient, it is likely to generate some type of disability (although in many cases the lost abilities may 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. This is why we have different classifications regarding the types of stroke.

In general, two large groups have been considered to exist, within which we can find various typologies.

Hemorrhagic stroke

Hemorrhagic stroke or cerebral hemorrhage is the type of stroke that occurs when one or more blood vessels rupture, 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 occur not only in the brain but also at the level of the meninges and inside the cerebral ventricles.

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

1.1. Stroke due to traumatic head injury

A head injury may in turn cause a stroke in the form of a cerebral hemorrhage.when the blood vessels of the brain rupture.

1.2. Aneurysmal stroke

Another common cause of cerebral hemorrhage is the presence of aneurysms, localized widening of blood vessels that occur due to weakened blood vessels.Aneurysms are localized widening of blood vessels that occur due to weakened blood vessels. These are blood-filled protrusions which, because they have a weakened wall, are easily ruptured by the pressure exerted by the blood flow.

1.3. Strokes due to AVMs and other malformations

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

2. Ischemic stroke

Also called cerebral infarction, ischemic stroke occurs when one of the arteries in the brain becomes blocked, causing it to interrupts blood flow to part of the brain.. This causes the brain tissue to lack the oxygen and nutrients necessary to survive, dying in a short time. Generally, when we talk about stroke, we usually refer to this type of stroke, being the most frequent of the major 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 obstructed comes from outside the nervous system and travels through the blood until it reaches the brain.It travels through the blood until it reaches the nervous system and causes ischemia if it is larger than the blood vessel through which it passes. It is usually a blood clot that detaches from its place of origin.

2.2. Stroke due to cerebral thrombosis or atherothrombotic stroke

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

2.3. Lacunar stroke or small vessel stroke

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

2.4. Transient ischemic stroke

This type of ischemic stroke occurs when one of the blood vessels supplying a part of the brain becomes blocked. that irrigate a part of the brain, but the system itself is able to overcome it so that the 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 more severe and permanent stroke, making it necessary for the affected person to carry out preventive strategies and controls of his or her state of health. It would be similar to the relationship between angina pectoris and a heart attack.

2.5. Hemodynamic stroke

This is a type of stroke in which there is a decrease in the Blood Pressure level, which causes the blood not to reach the patient's bloodstream with the correct amount of blood flow. which means that the blood does not arrive with sufficient force to properly irrigate the entire brain. Although there may not be an obstruction as such, it is considered within ischemic strokes.

Bibliographic references:

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