Ischemic Cerebral Stroke - Causes, Symptoms And Consequences

2024 Author: Josephine Shorter | [email protected]. Last modified: 2023-12-16 21:43

Ischemic cerebral stroke

Acute cerebrovascular accidents (ACVI) are common causes of hospitalization, while the diagnosis of ischemic stroke is confirmed in about 70-80% of patients over fifty years of age. Possible consequences of ischemic stroke are premature death, human disability. In many cases, a stroke can be avoided with the correct organization of the daily routine, correction of arterial hypertension, and prevention of atherosclerosis.

What is ischemic stroke?

Ischemic stroke (IS) is an acute violation of cerebral circulation, a consequence of a lack of blood supply, accompanied by the death of a brain area. Another name for ischemic stroke - "cerebral infarction" also reflects the essence of pathogenesis in the brain.

Do not confuse the terms '' cerebral infarction '' and '' myocardial infarction ''. In the latter case, the pathogenesis develops in the heart muscle, has other clinical manifestations.

The definition of the nosological form of the disease is based on three independent pathologies that characterize a local circulatory disorder, designated by the terms ischemia, infarction, and stroke:

Ischemia is a lack of blood supply in a local area of an organ, tissue.

The causes of ischemia is a violation of the passage of blood in the vessels, caused by (spasm, squeezing, cholesterol plaques, blockage by blood clots, emboli). The consequence of ischemia is a heart attack (necrosis) of a tissue site around the vessel and its basin (vascular branches), in front of the place where the blood stops.

Stroke is a violation of blood flow in the brain during rupture / ischemia of one of the vessels, accompanied by the death of brain tissue.

There are five main periods of completed ischemic stroke:

• sharpest;
• acute;
• early recovery;
• late recovery;
• remote.

Content:

• Pathogenesis of ischemic stroke
• Ischemic stroke symptoms
• Causes of ischemic stroke
• Types of ischemic stroke
• Disease prognosis
• Consequences and complications
• Treatment and prevention of ischemic stroke

Pathogenesis of ischemic stroke

The pathogenesis of the acutest stage determines the severity, duration of the disease, strategy, treatment tactics, prognosis of the outcome of the disease (death, disability, partial or complete recovery).

'' Ischemic cascade ''

The ischemic cascade (IC) in the most acute stage causes tissue hypoxia, acidosis, impaired lipid and carbohydrate metabolism, and a decrease in the synthesis of neurotransmitters. The development of IC is accompanied by the formation of a heart attack nucleus, apoptosis of brain cells and the development of secondary diffuse cerebral edema.

Two interrelated directions of the ischemic cascade:

• Formation of a heart attack. It is caused by a decrease in the rheological properties of blood, turbulence of blood flow, aggregation of erythrocytes, platelets, and the formation of emboli / thrombi. Stopping blood flow leads to cell apoptosis, the formation of a heart attack, which after a while is transformed into the heart attack nucleus, with penumbra - the penumbra or perifocal zone around the nucleus.

• Vascular reactions of cerebral blood vessels to changes in regional cerebral blood flow are accompanied by focal cytotoxic edema in the form of filtration perifocal edema, or reflex vasodilation - `` not restored blood flow ''. Disruption of the ATP-dependent sodium pump leads to damage to the blood-brain barrier, secondary-type vasogenic edema and diffuse cerebral edema.

Neurons - brain cells located in the penumbra retain structural integrity, do not perform functions, but have the potential for self-healing. Therefore, one of the tasks of the therapy of the most acute period is to restore the activity of neurons located in the penumbra.

Options for completing the pathogenesis of the most acute period of ischemic infarction:

1. positive dynamics - a decrease in cerebral and focal neurological symptoms (up to 16 points on the NIHSS scale);
2. stabilization - the absence of clear positive dynamics;
3. negative dynamics - a clear worsening of the condition (more than 16 points on the NIHSS scale).
4. Death (respiratory / cardiac arrest).

Further pathogenesis is diverse, depending on the indicators of the state of the patient's pathogenesis.

The main factors that affect the severity of pathogenesis:

• the size of the damaged cerebral artery and involvement in the pathogenesis of its basin;
• the patient's condition (age, previous chronic diseases);
• time to start resuscitation after the first symptoms;
• localization of a heart attack and the depth of damage to nerve connections;
• the state of the psycho-emotional sphere of a person on the eve of the disease.

Ischemic stroke symptoms

Signs of acute disorders of cerebral circulation are a reason for a person to seek medical help.

Determine relatives of the patient, by his appearance, behavior, response to irritation:

• disturbances of consciousness (from mild lethargy to coma);
• decrease / loss of pain sensitivity of body parts;
• decrease / loss of motor, voice functions;
• headache, vomiting.

Easy tests have been developed to determine if a patient has a stroke at home.

Symptoms of acute cerebrovascular accident (ACVA) are a reason for a person's hospitalization.

Symptoms of stroke is determined by the doctor of the ambulance resuscitation team. Uses the Face-Hand-Speech test, in the case of a coma patient - the GCS test (Glasgow Coma Scale). The doctor confirms the clinical conclusions by the results of blood pressure measurements (up to 80% high blood pressure is detected), an electrocardiogram (used to differentiate similar diseases).

Upon confirmation of stroke, the patient is immediately taken to the hospital. The sooner the patient is delivered to the hospital for emergency therapy, the more chances for a favorable outcome!

Inpatient ischemic stroke symptoms

Exclude diseases mimicking a stroke - migraine, epilepsy, myocardial infarction, extensive bleeding, aspiration pneumonia, heart, renal failure. Immediate neuroimaging (CT) is performed to determine the types of stroke or its precursor, a transient ischemic attack. Other instrumental methods are used, a laboratory blood test is performed.

Symptoms of transient ischemic attacks (TIA)

They often precede ischemic stroke, and sometimes TIA is a continuation of the stroke. The symptoms of TIA are similar to the focal symptoms of a minor stroke. The main differences between TIA and strokes are revealed by CT / MRI examination, by clinical methods:

• there is no (not visualized) focus of cerebral tissue infarction;
• the duration of neurological focal symptoms is not more than 24 hours.

TIA symptoms are confirmed by laboratory, instrumental studies.

• Blood for the purpose of determining its rheological properties;
• Electrocardiogram (ECG);
• Ultrasound - dopplerography of the vessels of the head and neck;
• Echocardiography (EchoCG) of the heart - revealing the rheological properties of blood in the heart and surrounding tissues.

Symptoms of the most acute stage of ischemic stroke

The characteristic signs of cerebral blood flow disorders are verified in brain studies using combined MRI studies using magnetic resonance (MR) diffusion and magnetic resonance (MR) perfusion (MRI options).

Both methods of MR tomography are of priority in assessing the dynamics of cerebrovascular accidents in the acutest stage of ischemic stroke.

• MR perfusion is a technique for identifying the zone of perfusion disorders in a few minutes, the heart attack nucleus one hour after ischemic stroke.
• MR diffusion is a technique for predicting the volume of the formed ischemic stroke focus.

The main indicators of cerebral blood flow (perfusion) - CBV, CBF, MTT in the zones of the infarction nucleus, ischemic penumbra - in the penumbra or perifocal zone - are diagnostic guidelines for determining possible options for restoring blood flow, determining a treatment strategy for the acute period of ischemic stroke.

These indicators characterize:

• cerebral blood flow rate (CBF ml / min / 100 g.);
• cerebral blood flow (CBV ml / 100 g.);
• the speed of passage of the contrast agent (MTT, sec).

Other methods of instrumental research are widely used, which, when performing certain tasks, are of great value in comparison with methods of research of perfusion and diffusion.

The main variants of cerebral blood flow syndromes after the completion of the acute stage:

• Normal perfusion blood flow - the absence of blood flow disturbances around the heart attack nucleus in the brain;
• Postischemic (reactive) hyperemia - persistence of cerebral blood flow disorders, a slight increase in the heart attack nucleus;
• Persistent chronic ischemia - preservation of the volume of perfusion disorders against the background of a slightly increasing volume of the heart attack nucleus;
• Acute pathological hyperperfusion - an increase in the blood flow rate, a preservation or slight decrease in the volume of blood flow against the background of an increasing volume of the nucleus, an increase in the zone of the formed infarction;
• Unrecovered perfusion - the absence of positive dynamics in the restoration of the blood flow rate, a catastrophic increase in irreversible ischemia.

The symptoms of advanced stages of stroke depend on many factors, discussed below.

Causes of ischemic stroke

Not all causes of ischemic stroke can be classified. Many clinical examples of unclear cardiovascular pathologies, especially in people under fifty years of age. According to various sources, up to 40% of all strokes at a young age do not have an established cause. Nevertheless, several classifications of causes have been proposed, one of them assumes a conditional division of causes into two main components.

Uncorrectable causes of ischemic stroke

• age;
• floor;
• hereditary predisposition;
• stress factors;

Uncorrectable reasons are given at birth or are due to random factors.

Annual risk of ischemic stroke stroke at age:

• 20 years old is 1/3000 people.
• 84 years and above - 1/45 people.

A significant increase in the likelihood of stroke occurring after age 45.

In women under 30 and after 80 years of age, the risk of ischemic stroke is significantly higher than in men of the same age, and from 30 to 80 years, men have more causes of stroke. This statement applies to different age groups, gender groups with no history of chronic diseases that have been proven to affect cerebral blood flow. A number of researchers have proven a high familial predisposition to cerebral infarction.

Correctable causes of ischemic stroke

Correctable reasons in decreasing order of importance:

• atherosclerosis;
• arterial hypertension;
• hypodynamia;
• osteochondrosis of the cervical region of the skeleton;
• obesity;
• diabetes;
• alcohol abuse;
• smoking;
• the use of oral contraceptives.

Correctable causes are the result of chronic diseases or bad habits.

The leading factors - atherosclerosis and arterial hypertension, are caused by a violation of lipid carbohydrate metabolism. The risk of developing atherosclerotic plaques begins at the age of twenty.

Maintaining normal blood pressure levels within (120/80), by about 40%, reduces the risk of ischemic stroke after forty years.

The use of oral contraceptives in young women significantly increases the risk of stroke, namely: the risk of stroke is 13/100000 in the case of taking contraceptives, versus 3/100000 in women who do not take these drugs. One of the possible reasons for this phenomenon is the hypercoagulation of blood cells under the influence of drugs.

Types of ischemic stroke:

Acute ischemic stroke

Acute is characterized by a sudden onset, rarely a gradual increase in clinical manifestations. Symptoms are noted on the one hand, consciousness is usually normal or slightly impaired.

The main neurological disorders detected in the acute period:

• dysphasia - speech disorder;
• dysarthria - distorted pronunciation of individual words;
• hemianopia - loss of half of the visual field;
• weakness;
• ataxia - impaired coordination of movements, a sense of balance;
• loss of sensitivity on one side of the body.

In most cases, the diagnosis of ischemic stroke, with the exception of its unusual onset in some patients, namely: gradual onset, lack of consciousness, nervous seizure. In this case, a differential diagnosis is made.

The following possible pathologies are excluded:

• migraine;
• postictal paresis;
• hypoglycemic coma;
• subcortical hematoma;
• brain tumor.

In some cases, similar diagnoses are considered:

• dissecting aneurysm of the carotid artery;
• infective endocarditis;
• giant cell arteritis
• atrial fibrillation,
• hypertensive encephalopathy.

In clinical practice, various methods are used to identify neurological deficits. The most common NIHSS scale. Accurate detection of cerebral infarction is performed in all patients by CT or MRI of the brain. Both methods are highly sensitive. In some cases, CT is a more affordable method. However, the choice of methods is entrusted to the council of doctors.

Laboratory blood tests during the acute phase of ischemic stroke include determining:

• general blood counts;
• blood glucose levels (hypoglycemia is accompanied by similar symptoms);
• prothrombin time;
• activated partial thromboplastin time.

Major ischemic stroke

Proximal occlusions of major cerebral arteries are characterized by extensive areas of perfusion disorders. Extensive strokes are the generic term for massive cerebral infarctions. They arise when there is insufficient collateral blood supply to large arteries. Massiveness is determined based on the volume of the infarction and the magnitude of the neurological deficit, the consequence of stroke, determined by CT or MRI methods. The characteristic volumes of carotid infarctions were established:

• atherothrombotic stroke (atherosclerosis of large arteries) - 115 cm ³
• cardioembolic (blockage of an artery by an embolus) - 62 cm ³
• hemodynamic (decreased blood flow) - 32 cm ³
• lacunar (defeat of small adjacent arteries) - 2 cm ³
• rheological stroke (rheological changes in fibrinolysin) 1.5 cm ³.

Extensive cerebral infarctions occur in the carotid basin (carotid arteries) and vertebro-balisyar basin.

Carotid basin:

• internal carotid artery
• middle cerebral artery
• anterior cerebral artery
• posterior cerebral artery

Wind-basilar basin:

• vertebral artery;
• basilar artery

The clinical symptoms of extensive ischemic stroke of the left / right hemispheres of the brain are due to a decrease in cerebral circulation, cerebral hypoxia. In this case, a pathological process develops with a pronounced violation on the opposite side of the body.

General cerebral symptoms:

• disturbances of consciousness of varying degrees,
• vomiting
• sharp headache
• vestibular disturbances (dizziness, unsteadiness of gait).

Focal neurological symptoms

• movement disorders (paresis and paralysis)
• swallowing disorders
• vision
• speeches
• cognitive impairment
• which depend on the localization of the focus and the vascular area of the lesion.

Lacunar ischemic stroke

There are no perfusion disorders in the nucleus and penumbra of ischemia. This type of ischemia is not visualized on the first day. There are no cerebral disorders.

It is characterized by high blood pressure at the onset. The pathogenesis of lacunar ischemia (LI) is diverse and is determined, in descending order of the frequency of occurrence of pathogenetic subtypes of lacunar stroke:

• a history of hypertension of a patient with lacunar ischemia;
• atherosclerotic changes in the vessels;
• embolism of the perforating arteries of the brain.

Determination of the pathogenetic subtype of LI is revealed by clinical methods, MR diffusion (MRI variant), Doppler monitoring of the cerebral arteries, and laboratory blood tests.

1. Lacunar ischemia with a history of hypertension:

• a history of a patient admitted to the clinic with chronic hypertension with a crisis character of exacerbations;
• high blood pressure;
• instrumental studies do not reveal the sources of cardiac embolism, atherosclerotic plaques in the arteries of the head;
• normal blood cholesterol levels;
• Doppler monitoring of microemboli in the arteries of the brain is not detected;
• MR diffusion reveals a single small, approximately 15 mm LI focus, or its absence.

2. Lacunar ischemia with a history of vascular atherosclerosis:

• increased blood cholesterol and / or low density lipoprotein levels;
• atherosclerotic plaques in the vessels of the brain;
• MR diffusion reveals lacunar foci of one 15 mm and more or several small ones less than 15 mm.

3. Lacunar ischemia caused by embolism of cranial vessels:

• in the history of the admitted patient, previously transferred cerebral or myocardial infarctions, the presence of potential sources of emboli from the cavity of the heart and cerebral vessels;
• at the onset and three weeks after, a severe neurological deficit is revealed according to the NIHSS scale;
• Doppler monitoring reveals the presence of microemboli of the cerebral arteries;
• MR diffusion reveals multiple lacunar foci in several vascular basins, one to three large foci more than 15 mm in the basin, or a combination of lacunar and territorial foci.

Disease prognosis

In practice, several options for the clinical assessment of the patient's condition after a stroke are used, including the assessment of the patient's neurological condition is carried out in dynamics, upon admission and discharge of the patient according to three independent scales (NIHSS, Rankin, Bartel). These scales are most widely used for research purposes.

1. NIHSS scale

The NIHSS scale is a point assessment of the severity of neurological disorders in the acute period of ischemic stroke. It is intended for an objective assessment in dynamics, the patient's condition, the prognosis of the outcome of ischemic stroke.

The sum of points, scored on the result of the survey:

• less than 10 points - patient recovery within a year with a probability of up to 70%;
• more than 20 points - the patient's recovery within a year with a probability of up to 16%.
• more than 3-5 points - an indication for therapy with the aim of resorption of a thrombus in the heart attack;
• more than 25 points - a contraindication for thrombolytic therapy.

The NIHSS scale assumes an assessment of the neurological state, using generally accepted methods of clinical examination of reflexes, sensory organs, and the patient's level of consciousness. The results are ranged from the minimum indicators - burrow or close to normal, to the maximum - reflecting the degree of neurological damage.

The patient's condition is determined by the indicators:

• level of consciousness - performing simple actions at the request of the researcher, meaningfully answering simple questions;
• oculomotor reactions (reflexes) - the ability to perform simple coordinated movements of the pupils of the eyes;
• vision - tracking a moving object with a gaze;
• mobility of facial muscles - performing mimic actions (smile, closing eyes);
• control of the movement of the upper and lower extremities - the ability to passively lower the arm (10 sec.), legs (5 sec.) from the position of the arm, leg set by the researcher;
• control of the coordination of movements of the muscles of the extremities - the ability to perform finger-nose and heel-knee tests;
• pain sensitivity - a response to a slight pricking of the skin;
• speech function - the ability to meaningfully describe the image in the presented picture, name the objects in the picture, read sentences from the proposed list;
• attention - the ability to perceive information.

The study is carried out at the same pace, the patient is not informed about the purpose of the examination, and the patient is not prepared for the tests. The test is conducted by a trained neurologist.

2. Rankin scale - RS (modified)

Designed to determine the functional capacity of the patient after a stroke. It is used to obtain objective information about the dynamics of symptoms, to assess the effectiveness of rehabilitation measures, the need to use assistive devices for movement.

The Rankin scale is ranked according to five degrees of impairment:

• No violations.
• The first degree is a slight loss of legal capacity. Persistence of neurological disorders for some time after a stroke (see the NIHSS scale). The main criterion for determining the first degree of violations, the answer is the question: `` What usual actions did I do before the stroke, but now I can't? '' (Habitual affairs are those that are done more often than once a month).
• Second degree - mild disability. The main criterion is that the patient can stay at home unattended for more than one week.
• Third Degree - Medium Disability. The main criterion is that the patient moves independently, control more than once a week over the performance of actions around the house, psychological, intellectual advice is required (conducting financial affairs, the like).
• Fourth degree - moderate to severe disability. The main criterion is that the patient moves independently, needs constant care during the day.
• Fifth degree - severe disability. The main criterion is that the patient cannot move, is not able to serve himself on his own.

3. Bartel Index (IB)

It is used to assess the results of treatment of patients after a stroke.

Indicators are taken into account that reflect the ability of patients who have suffered a stroke to independently perform simple household actions at the stage of recovery (eating, transplanting in bed, taking a shower, dressing, controlling urination and defecation, etc.). The results are ranked 100 points. The maximum 100 points is the norm, the minimum is 60 and below - independent existence is impossible.

Consequences and complications of ischemic stroke

Recommendations for reducing the risk of ischemic stroke

The recommendations are based on the '' Guidelines for the Management of Patients with Ischemic Stroke and Transient Ischemic Attacks '', 2008, prepared by the team of the Executive Committee of the European Stroke Organization (ESO)

• Patients with diabetes mellitus are recommended to maintain blood pressure at the level (130/80), its correction should be carried out with `` Statins '' - pharmacological drugs used to reduce the level of cholesterol and atherogenic lipoproteins in the blood (Atoris, Akorta, Atomax, Atorvastatin, Vazimip, Vero -Simvastatin, Zokor, Zokor-forte, Cardiostatin, Lescol Forte, Liptonorm, Mertenil, Ovenkor, Rosucard, Rosulip, Roxera, Simva Hexal, Simvastatin Alkaloid, Simvastol, Simvar, Simgal, Tarkaverd, Tulip, Hollestar and others). All drugs from the pharmacological group - statins - have limitations and contraindications.
• Smoking doubles the risk of ischemic stroke, quitting smoking significantly reduces the risk of ischemic stroke by 50%
• Alcohol, high (60 g / day and more), moderate (12 to 24 g / day) doses increase the risk, while low (12 g / day) doses, on the contrary, reduce the risk of ischemic stroke. Alcohol abuse is associated with hypertension.
• Moderate physical activity, physical activity during free time from work (2-5 hours / week) significantly reduce the risk of ischemic stroke.
• Body mass. Mass index is more than 25 units. It is an equal cause of strokes for men and women in view of hypertension and the risk of developing diabetes in this category. A large belly in men increases the risk of stroke; in women, no dependence has been identified. Weight loss significantly reduces the risk of cardiovascular disorders, but not strokes.
• Postmonausal and estrogen replacement therapy in women. It has been proven that the risk of stroke increases in women taking substitution therapy for a long time (more than five years).

Ischemic stroke is one of the causes of disability among citizens. How do I get a disability?

The list of documents required for examination at the Bureau of Medical and Social Expertise (ITU):

1. Application of a citizen of the Russian Federation / his legal representative (notarized power of attorney).
2. Identity document - passport of a citizen of the Russian Federation.
3. Referral for medical and social examination (signed by the chief physician, certified by the seal of the institution);
4. A copy of the work book (certified at the place of work).
5. Medical documents confirming the state of health of a citizen (outpatient card, hospital extracts, consultants' opinions, examination results).
6. For working citizens - professional and production characteristics from the last place of work (according to the approved form).

Treatment and prevention of ischemic stroke

The algorithm of medical tactics includes: diagnosis of stroke, prediction of consequences. Based on this, the choice of optimal therapy tactics is carried out. The most promising area of treatment for ischemic stroke are:

• active reperfusion - restoration of blood flow;
• neuroprotection - preventing the destruction of nerve cells in the penumbra.

List of drugs for the treatment of the most acute period of ischemic stroke:

• Recombinant tissue plasminogen activator rt-PA (Aktilize)
• Enzyme inhibitors (Catopril, Enalopril, Ramnopril)
• Angiotensin II receptor blockers (Losartan, Condesartan)
• Platelet antiplatelet agents (Aspirin, Ticlopidine, Clopidopel, Dipyridamole, Pentaxifylline);
• Low molecular weight dextrans (Rheopolyglucin);
• Antagonists of glutamate and its receptors (Glycine, Rizulol, Lubeluzole);
• Calcium antagonists (Nimodipine);
• Antioxidants / antioxidant precursors (Mexidol, Alpha-tocopherol, Carnosine, Mildranat, Actovegin);
• Drugs affecting tissue metabolism (Inosie-F, Riboxin, Cytochrome C);
• Diuretics (Furosemide).

On the subject: folk remedies to help

In some cases, surgical methods of treatment are used to effectively treat ischemic stroke, including recanalization (removal) of a vascular thrombus, carotid endaterectomy (CEAE), angioplasty, and stenting of the carotid arteries.

Author of the article: Sokov Andrey Vladimirovich | Neurologist

Education: In 2005 completed an internship at the IM Sechenov First Moscow State Medical University and received a diploma in Neurology. In 2009, completed postgraduate studies in the specialty "Nervous diseases".