Stroke

Generality

The term stroke and its numerous synonyms ( stroke, apoplectic attack, cerebral infarction, stroke, etc.) indicate a loss of brain function, caused by insufficient blood supply to a more or less extensive area of the organ.

Figure: the image emphasizes the importance of immediate intervention of medical aid in the presence of the typical symptoms of stroke. From the site: strokeupdate.co.uk

According to the definition of the WHO (World Health Organization), in order to talk about stroke the following points must be met:

rapid appearance of signs and / or symptoms, due to a loss of brain function (focal or global), which:
- they must have a duration of more than 24 hours;
- they must not be attributable to other apparent causes other than vascular origin.

The main risk factors are represented by hypertension, atherosclerosis, cigarette smoking and alcohol abuse; not surprisingly, therefore, stroke is more frequent in men than in women and in industrialized countries compared to developing ones.

The symptoms are different and depend on different factors, such as the severity of the stroke, the area of the brain affected, the causes, etc .; the same applies to complications. The symptomatology can therefore be more or less reversible in the short term, while the long-term consequences can be partially corrected by adequate rehabilitation.

The most appropriate therapy is planned, case by case, based on the characteristics of the stroke, which affects an individual. The rapidity and timeliness of relief and prevention are essential.

What is a stroke?

Stroke, also known as stroke, is a serious pathological condition, which occurs when blood supplies to the brain are interrupted or severely reduced. Without this basic blood supply, the brain tissue begins to die from the absence of oxygen and nutrients.

Stroke is characterized by a sudden onset and, due to the deleterious effects it can have, requires immediate intervention. In fact, first we act with the appropriate countermeasures, and the less the brain damage will be.

Epidemiology

The incidence of stroke, in Italy and in the world, is very high; in our country, every year, it affects more than 200, 000 people, of which 80% are new episodes while the remaining 20% relapse (ie patients who have already had a past episode of stroke).

Still at national level, stroke is one of the major causes of death (the third, after heart disease and cancer ), and of disability. In fact, approximately 10-12% of all deaths and the majority of disabled adults are owed to it.

The individuals most at risk are the elderly; not surprisingly, 75% of stroke cases involve people aged 65 and over, while the remaining 25% involve younger people (including children).

If we think, then, that the population of industrialized countries is aging more than in the past (we live longer and longer), we can guess why the incidence of stroke is destined, in the future, to increase further .

Men are more affected than women, and the thesis according to which there are more predisposed breeds than others is by now consolidated: in fact, Asians, Africans and the Caribbean are, by far, the populations most at risk. The reason is due to a natural tendency of these ethnic groups to develop diabetes and heart disease, which are two of the most important factors triggering the stroke.

The epidemiology of stroke in brief:

More than 200, 000 cases every year, in Italy
Third cause of death in industrialized countries
More frequent among the elderly: 75% of cases are aged 65 and over.
Frequent cause of disability in adulthood
More frequent among Asians, Africans and Caribbean

Causes of stroke

WHY INSECTS ICUS?

Stroke occurs when the supply of blood to the brain is completely interrupted or largely reduced. This situation can occur due to an embolism, thrombosis or cerebral haemorrhage . This last condition, rarer than the previous ones, is often deadly.

WHERE IS ICT?

Often, the primary site of the disease is not the brain, but the heart or arterial vessels . As anticipated, in the great majority of cases, the obstacle to the blood flow responsible for the stroke is, in fact, determined by the presence of a clot ( thrombosis ), of a fragment of it detached from the artery in which it was formed ( embolism ), or from the rupture of an arterial wall ( hemorrhage ).

Types of Stroke

On the basis of the triggering causes, two forms of stroke are distinguished, each of which is divided into as many subgroups:

Ischemic stroke, whose subgroups are:

Thrombotic stroke, if it is due to thrombosis
The embolic stroke, if it is due to an embolism

Hemorrhagic stroke, whose subgroups are:

Intracerebral hemorrhagic stroke
Subarachnoid hemorrhagic stroke

For completeness of information, it is appropriate to specify that there is also another particular form of ischemic stroke, called transient ischemic attack ( TIA ).

Figure: this is what happens in the ischemic stroke (occlusion of a blood vessel) and in the cerebral stroke (rupture of a blood vessel). From the site: hardoctor.wordpress.com

The symptoms, with which the latter occurs, are quite similar to those of ischemic stroke (so much so that it is not possible to distinguish them except with a precise diagnosis); the only difference is that these symptoms, instead of being permanent as in the stroke, are exhausted after a short time (this is why it is called transitory).

ICTUS ISCHEMICO

Ischemic stroke is the most common form of stroke (approximately 85% of cases). It occurs following a narrowing, or complete closure, of one of the arterial vessels that pass through and supply the brain ( ischemia ). Ischemic stroke can be thrombotic or embolic.

Thrombotic type ischemic stroke

When there is thrombosis at the origin of the stroke, it is called a thrombotic ischemic stroke . In such situations, the interruption of the blood circulation is due to the formation of a blood clot, well anchored to the arterial vessel within which it originates. The thrombus (as this blood clot is called) is often subsequent to a vasal lesion (favored by hypertension) and is caused by the accumulation of platelets and cholesterol ( atherosclerotic plaque ).

Ischemic stroke of embolic type

When the cause of the stroke is an embolism, we speak of an embolic ischemic stroke . In these cases, the blood clot is not anchored to the wall of a vessel, but is detached and travels in the circulatory stream; if it does not melt in time, it is pushed into vessels of smaller and smaller diameter, until it remains stuck for its size; in this way, it acts as a "stopper" drastically reducing the normal blood flow downstream of the obstruction. The embolus (this is the name that takes the blood clot) usually originates in the heart and flows into the brain only later.

HEMORRAGIC ICTUS

The hemorrhagic stroke occurs when a blood vessel, which irrigates the brain, breaks or suffers a loss of blood, giving rise to the so-called cerebral hemorrhage . The main causes of cerebral hemorrhage are:

Chronic hypertension
A brain trauma
An aneurysm
A congenital arteriovenous malformation

The hemorrhagic stroke can be classified, based on the type of hemorrhage, in intracerebral hemorrhagic and subarachnoid hemorrhagic.

Intracerebral hemorrhagic stroke

Hemorrhage is intracerebral when the rupture of the blood vessel occurs within the brain. The blood that escapes, in addition to no longer replenishing the brain areas to which it was destined, exerts pressure on the surrounding brain tissue, damaging it.

Subarachnoid hemorrhagic stroke

Hemorrhage is subarachnoid when an arterial vessel located on the surface of the brain is broken, in the space between it and the skull. The appearance of this disorder is usually due to the rupture of an aneurysm and is reported by a sudden headache.

As in the previous case, after hemorrhage there is no supply of oxygen and nutrients to the brain tissue involved, which slowly begins to die.

What is an aneurysm?

To learn more: Aneurysms

The term aneurysm identifies a permanent pathological dilation of a blood vessel, usually arterial. The bulge, which resembles a ball, makes the vessel wall weaker and prone to breakage. Once the jar is broken, blood comes out of it, sometimes in considerable quantities. Hemorrhage damages the tissue surrounding the place of leakage and deprives of oxygen and essential nutrients the areas to which the lost blood was destined.

An aneurysm can develop in the brain or aorta, with dramatic results.

Risk factors

The risk factors associated with the appearance of a stroke are numerous. They can be divided into two categories: potentially treatable risk factors and untreatable risk factors.

By potentially treatable risk factors we mean all those situations, also linked to a heart attack, for which there is a pharmacological or behavioral remedy. For example, chronic hypertension (one of the main risk factors for stroke) can be treated either by hypotensive drugs or by adopting a healthy lifestyle (hyposodic diet and movement).

By untreatable risk factors, on the other hand, we mean some non-modifiable characteristics of the patient, such as age, race, genetic predisposition, etc.

The potentially treatable risk factors:

Chronic hypertension (pathological levels exceed 120/80 millimeters of mercury, mmHg)
Smoking and passive smoking
High cholesterol
Diabetes
Obesity and overweight
Physical inactivity
Cardiovascular diseases
Contraceptive pill and hormonal therapy (based on estrogen).
Excess alcohol
Use of drugs (cocaine and methamphetamine)

Untreatable risk factors: