Cerebral ischemic stroke
Ischemic stroke is a disruption of blood flow to the brain due to an occlusion of an artery, which causes insufficient oxygen and nutrient transport to that organ, followed by the death of its cells. This condition can cause symptoms that depend on the type of vessel affected and the portion of the brain affected by this pathology.
What's a stroke? What does it mean? The word "stroke" (or "stroke" or "brain attack" - for the Anglo-Saxons, this condition is called "stroke") is a Latin word that means "stroke", as it is a real trauma that our brain undergoes and which is caused by an alteration in the flow of blood inside the skull.
Two major types of stroke are distinguished:
- Hemorrhagic, caused by the rupture of one or more blood vessels and leading to the formation of an intracranial hemorrhage, which compresses the brain tissue and induces tissue distress;
- Ischemic, generated by an ischemia of the encephalic tissue, that is, from a deficient arterial blood flow to a specific portion of the brain, with consequent tissue suffering.
In theischemic stroke, this drop in flow can be caused by three different reasons:
- Thrombosis, that is by the presence of a mass of platelets and blood elements called "thrombus" that is created inside the brain and which clogs the vessel;
- Embolism, that is, the presence of a foreign body (such as a clot from another site, a piece of plaque or fat globules) within the blood flow that leads to the occlusion of the vessel.
- Hypoperfusion systemic, i.e. a condition of decreased blood flow at a systemic level with a consequent imbalance between the oxygen and nutrient requirements of the tissues and the transport capacity of blood.
These causes lead to a reduction in blood flow in a specific area of the brain, with the consequent appearance of the characteristic symptoms.
If this condition resolves spontaneously in a short period of time (less than an hour from the moment of the onset of the alterations), we speak of TIA, or Transient Ischemic Attack. In fact, in that period of time, the triggering cause is eliminated, allowing complete recovery in the patient.
If, on the other hand, the symptoms persist for a period of time exceeding an hour, we speak of stroke true ischemic, with a much worse prognosis than TIA.
Risk factors and causes
They are generally divided into two broad categories: those that cannot be changed, such as age and gender, and those that can be changed.
Among the latter, the most important risk factors for stroke are:
- Atrial fibrillation, which favors the formation of thrombi in the heart atria and their subsequent embolization in the brain
- Dyslipidemias, i.e. changes in blood lipid values, mainly cholesterol and triglycerides. These changes can lead to the formation of atherosclerotic plaques, which are plaques made up of aggregated lipid material on the wall of major arteries, including the carotids. This formation can ulcerate and lose material, which is sent into the circulation to obliterate the lumen of a cerebral artery, causing aischemia;
- Cardiovascular diseases such as heart disease and valve diseases;
- Diabetes mellitus;
- Cigarette smoke;
- Excessive alcohol consumption
- Sedentary lifestyle.
What are the main symptoms of ischemic stroke? The genesis of the symptoms in patients it is immediate and sudden and the type of warning symptoms it is strictly dependent on the vessel concerned and on its territory of vascularization at the cerebral level, as each brain area has a different task from the others. In particular, we have five symptoms that must make the "antennae stand up":
- Presence of a sudden tingling (paraesthesia or hypoesthesia) o muscle weakness, which can lead to complete muscle paralysis, in the face or limb;
- Mental confusion, difficulty speaking and understanding what is happening (dysarthria or aphasia);
- Visual problems in only one of the two eyes, such as double vision (diplopia);
- Difficulty walking, with dizziness is lost of equilibrium o coordination;
- Very strong and lightning fast ill of head, for no apparent reason.
In case of strong suspicion, it is necessary to call an ambulance promptly, avoiding going to the hospital by own means. There is absolutely no need to waste time, as every lost minute can change the prognosis and post-attack quality of life.
In severe cases, paralysis may appear (paresis or plegia) of half of the body (hemisyndrome) usually on the side of the body opposite that of the ischemic side of the brain.
A physician is usually able to recognize an ischemic stroke based on the patient's and family's medical history, along with the symptoms and how they occur. By examining the patient, he can then hypothesize the site where ischemia is occurring.
Detections are performed immediately parameters and exams, aimed mainly at evaluating:
- There blood pressure;
- Blood tests including blood count, renal function, indices of inflammation, ionmia;
- THE glucose levels blood (glycaemia), as the low concentration of glucose (called hypoglycemia) determines a presentation symptomatology similar to ischemic
A is then performed Brain CT (Computerized Tomography, often erroneously abbreviated as CT scan), in order to be able to distinguish between the two types of stroke, hemorrhagic and ischemic, but also to make a differential diagnosis with other possible causes. If available, a magnetic resonance imaging is performed (MRI of the brain), which diagnoses lesions of the brain tissue even after a few minutes from the start of the event.
Thereafter, tests are conducted to understand the underlying cause of the ischemic pathology. Among others, the following are carried out:
- Electrocardiogram (ECG), for the study of heart beat and rhythm;
- Ultrasound of the heart (echocarygram), in order to check for any structural or pump anomalies;
- Checks on the caliber of the main arteries of the body, for example the carotids, by means of echocolordoppler, standard angiography or by means of a CT or MRI;
- More thorough blood tests, including coagulation tests.
Prognosis and consequences
What are the consequences of ischemic stroke? Stroke is a leading cause of death in the Western world. If it is not recognized in time and if you do not act promptly, the patient can suffer irreversible brain injuries that lead to death in a short time. The timely action instead allows to quickly restore cerebral circulation, reducing the percentage of irreversible neuronal lesions.
Overall, of all those who manage to survive an ischemic event, the 15% is hospitalized in long-term care wards, the 35% develops a marked limitation of daily activities, while the 20% requires assistance in walking.
The ability to access facilities and staff dedicated to the management and care of stroke, called "stroke units", is essential. Their goal is to promptly recognize the cause of the stroke, implementing a therapy aimed at the immediate restoration of the encephalic blood circulation.
Each patient is therefore treated as a separate case, trying to minimize the risk of death and irreversible brain damage, avoiding ischemic recurrences, controlling the underlying cause of the ischemia and favoring as much as possible the recovery of the abilities compromised by the disease. .
Immediate drug treatment
We have clarified that the blood, in order to be able to give ischemic pathology, spontaneously forms these aggregates, called clots, which occlude the arteries. In order to dissolve them, therapy is administered thrombolytics through the tPA, or plasminogen activator, within 4 hours of the onset of symptoms.
If there are contraindications to using this drug, they can be used for the same reason anticoagulants (like theheparin) or antiplatelet agents platelets (like theaspirin and the clopidogrel) depending on the cause of the cerebral ischemia.
If the cause is linked to the presence of an atherosclerotic plaque of a large artery, such as the carotid artery, the possibility of using specific instruments aimed at removing the cause of the blockage of the circulation in the brain can be considered. There are two possible interventions:
- Carotid endarterectomy, in which, through an incision on the neck, the carotid artery is intervened, eliminating the occluded portion of the atherosclerotic plaque and replacing it with small pieces of artificial tissue.
- Angioplasty and stent, in which a small expandable metal tube, called a stent, is used, which is conducted at the level of the atherosclerotic plaque and is inflated to reopen the blocked vessel.
There rehabilitation of the patient should be designed and decided through the active interaction of the patient and his family with an interprofessional team, headed by a physician experienced in the recovery of post-stroke functions together with a group of professionals specialized in the recovery of lost functions, including which speech therapists, for the recovery of communication skills and social interaction; physiatrists, for the recovery of osteo-muscular function; psychologists, since about 1/3 of stroke patients undergo a depressive syndrome; nurses, for the care and cleaning of the sick. This working group must actively discuss the patient's clinical picture, clarifying the active problems, the primary rehabilitation objectives, any improvements or worsening. The patient should be informed about the severity of the clinical picture, the recovery time and the possible long-term consequences that the stroke can cause.
It can to prevent ischemic stroke? Appropriate information on stroke is necessary, especially as regards alarm symptoms, in order to be able to act actively and promptly on the ischemic problem, reducing the percentage of neurological damage. In the event that one is subject to TIA, continuous and frequent monitoring of the state of health is essential, as this population has a 40% greater risk of stroke than the normal population.
It has also been shown that there is a lifestyle that allows you to drastically lower the risk of stroke:
- Avoid smoking
- Maintain a healthy body weight by reducing the consumption of salt and animal fats;
- Consume fish 2 - 4 times a week
- Regularly consume three servings of vegetables and two of fruit per day
- Engage in physical activity
- Limit alcohol intake
- Check your blood sugar and blood pressure periodically