Stroke: Overview of Information

Stroke is an acute disorder of the cerebral circulation, which is characterized by sudden (within minutes, less often - hours) appearance of focal neurologic symptoms (motor, speech, sensory, coordinative, visual and other disorders) and / or cerebral infringements (impaired consciousness, headache, vomiting etc.), which persist for longer than 24 hours or lead to the death of the patient in a shorter period of time as a result of the cause of cerebrovascular origin. 

Strokes (acute impairment of cerebral circulation) is a heterogeneous group of diseases caused by sudden focal cessation of cerebral blood flow, which causes the appearance of neurological disorders. Strokes can be ischemic (80%), usually due to thrombosis or embolism; or hemorrhagic (20%) due to rupture of the vessel (subarachnoid or parenchymal hemorrhage). If focal neurological symptoms are resolved within 1 h, a disorder of cerebral circulation is classified as a transient ischemic attack (TIA). When a stroke occurs, damage to the brain tissue occurs, with TIA, if the lesions occur, they are significantly less extensive. In Western countries, stroke ranks third in the list of causes of death and the first among neurological diseases - in the list of causes of disability.

With a sudden blockage of the cerebral artery, supplying blood to the brain region, the function of the affected area of the brain is immediately lost. If the occlusion persists for a certain time, the brain tissue undergoes necrosis with the development of a cerebral infarction, which can lead to irreversible loss of function. In this regard, the goal of stroke treatment is to restore the blood supply (reperfusion) of the affected area, limit the amount of damage by increasing the resistance of the brain to ischemia and preventing subsequent arterial occlusion. Although the achievement of these goals is associated with a number of difficulties, recently there has been progress in developing effective treatments. This chapter discusses drugs that prevent ischemic stroke and limit the associated damage to the brain tissue.

[1], [2], [3], [4], [5]

What causes a stroke?

The risk of stroke is increased in cases of stroke in individual or family history, in elderly patients and in males, in chronic alcoholism, in the presence of arterial hypertension, smoking, hypercholesterolemia, diabetes mellitus, and with the use of certain drugs (particularly cocaine, amphetamines). Certain risk factors are associated with specific variants of cerebral circulation disorders (for example, thrombotic stroke is most likely in hypercoagulation, embolic stroke in atrial fibrillation, subarachnoid hemorrhage can be expected in patients with intracranial aneurysm).

Symptoms of a stroke

In stroke, the arteries of the anterior vascular basin (consisting of the internal carotid artery and its branches, the posterior vascular basin, consisting of vertebrates and the main arteries, are affected.

The nature of the neurologic symptoms of stroke corresponds to the localization of the lesion. Stroke in the anterior vascular basin, as a rule, is accompanied by unilateral neurologic symptoms, while a stroke in the posterior vascular pool often causes bilateral disorders, often with a violation of consciousness.

Focal neurologic symptoms of stroke alone do not allow us to determine the type of stroke, but some additional symptoms allow us to make assumptions. In particular, an acute and intolerable headache is most likely a symptom of a subarachnoid hemorrhage. A disorder of the mind or coma, often accompanied by headache, nausea and vomiting, suggests an increased intracranial pressure due to edema that usually develops after 48-72 hours with extensive ischemic strokes and at an earlier time in most cases of hemorrhagic strokes. The growth of edema is fraught with the development of a fatal transientorial wedging of the brain.

Classification according to ICD-10

• Ischemic strokes

Depending on the mechanisms of development of ischemic stroke, its following subtypes are distinguished: atherothrombotic, cardioembolic, lacunary, hemodynamic as hemorheological micro-occlusion.

• Intracerebral haemorrhage
• Subarachnoid hemorrhage
• Vascular cerebral syndromes in cerebrovascular diseases
• Syndrome of the middle cerebral artery, anterior cerebral artery, posterior cerebral artery, stroke syndrome in the brainstem, syndromes of Venedikt, Claude, Fauville, Miyar-Gübler, Wallenberg, Weber, and others.
• Effects of cerebral strokes
• Transient ischemic attacks (TIL)

Transient cerebral ischemic attacks (attacks) and related syndromes, vertebrobasilar arterial system syndrome, carotid artery syndrome (hemispheric), multiple and bilateral syndromes of cerebral arteries, etc.

[6], [7], [8]

Stroke Diagnosis

The purpose of the clinical examination is to confirm the diagnosis of a stroke, determine its nature (ischemic or hemorrhagic) and assess the need and scope of urgent measures.

Stroke should be suspected when there is a sudden development of neurological deficit, corresponding to the defeat of a certain zone of the arterial blood supply of the brain; especially when a sudden occurrence of severe headache, impaired consciousness or coma. An emergency CT of the brain is shown for differentiating hemorrhagic and ischemic stroke and revealing signs of intracranial hypertension. CT has a sufficiently high sensitivity for detecting foci of hemorrhage, however, in the first hours after an ischemic stroke in the anterior vascular basin, pathological changes in CT are unlikely. CT is also likely to fail to detect a small-scale ischemic stroke in the zone of the posterior vascular basin and up to 3% of subarachnoid hemorrhages. In cases where a violation of consciousness is not accompanied by obvious signs of lateralization, additional types of research are shown to establish the causes of the disease that are not related to the stroke. If the clinical diagnosis of stroke is not confirmed by CT results, an MRI is shown to verify the ischemic nature of the disease.

After determining the type of stroke, try to establish its causal relationship with the patient's existing concomitant diseases and conditions, such as infection, dehydration, hypoxia, hyperglycemia, hypertension).

Treatment of stroke

For a complete examination, you may need to stabilize the patient. As part of ongoing activities, the provision of artificial ventilation for patients with coma or stunned conditions, monitoring of intracranial hypertension and measures to stop cerebral edema should be considered. Symptomatic therapy and correction of concomitant disorders (ie, hyperthermia, hypoxia, dehydration, hyperglycemia and hypertension) are vital in the acute period and in the period of convalescence. The specific treatment of stroke in the acute period varies depending on the type of stroke. In the period of convalescence, measures to prevent aspiration, deep vein thrombosis, urinary tract infection, pressure sores and exhaustion (in immobilized patients) may be required. The early onset of passive gymnastics of paralyzed limbs and respiratory gymnastics for the prevention of contracture, atelectasis of the lungs and pneumonia is shown. Most patients require highly specialized drug therapy with active support for physical methods of treatment to achieve maximum functional recovery. Some patients require additional types of interventions (for example, treatment of speech defects, diet therapy). To treat post-stroke depression, antidepressants may be required, but in most cases there is enough psychotherapeutic support. In the rehabilitation period, the interdisciplinary approach is optimal. It is necessary to promote the improvement of the patient's way of life (for example, refusal of smoking) in order to prevent a stroke.