Transient ischemic attack in the elderly

Introduction

Introduction to transient ischemic attack in the elderly Transientcerebralischemicattack refers to a local blood supply disorder that occurs briefly and frequently recurrent, resulting in a sudden transient focal neurological dysfunction in the blood supply area. Each episode lasts for several minutes to 1 hour, no more than 24 hours. That is, it is completely recovered, but it can be repeated. basic knowledge The proportion of illness: 0.0652% Susceptible people: good for 50 to 70 years old Mode of infection: non-infectious Complications: aphasia

Cause

The cause of transient ischemic attack in the elderly

Microembolism (20%):

Microemboli can be derived from the extracranial artery or heart. The former is more, the contents of aortic-cerebral atherosclerotic plaque and the debris of the wall thrombus clot when ulceration occurs. These are cellulose, Microemboli composed of platelets, white blood cells and cholesterol crystals enters the brain to form microembolism, which presents with ischemic symptoms. The embolus is tiny, easily ruptured, or decomposed by the action of enzymes, or is blocked by distal vascular ischemia. The expansion causes the emboli to move toward the distal end of the blood vessel, causing the blood supply to recover, and the symptoms disappear. Animal experiments have shown that the micro-emboli of the same source is sent to the same cerebral arteries again and again because the blood flow in the blood vessels is stratified. The clinical symptoms of recurrent episodes, the embolus of the source heart is relatively large, the embolization duration is longer, mostly more than 1h, because only 8% of carotid angiography is abnormal; and within 1h, most of the arterial to arterial embolism, because 37 % has arterial stenosis.

Hemodynamic changes (15%):

Severe stenosis or occlusion of the internal carotid artery or vertebral-basal artery, mostly caused by arteriosclerosis, poor blood vessel elasticity, weakened self-regulation ability, and can still maintain blood supply by collateral circulation. Once blood pressure is lowered, cerebral blood flow is reduced. The ischemic symptoms can occur in the blood supply area of the collateral circulation, the blood pressure rises, the collateral circulation recovers, and the symptoms disappear.

Vasospasm (10%):

Often due to severe hypertension and microemboli in the stimulation of nearby small arteries, but in severe arteriosclerosis, blood vessels are not prone to paralysis, it is controversial, and more and more clinical and animal experiments have confirmed cerebrovascular It can occur, such as subarachnoid hemorrhage, cerebral angiography, surgery, cerebral embolism can occur, cerebral atherosclerotic stenosis, stenosis of the wall wall, such as turbulent acceleration, can stimulate the blood vessel wall Vasospasm, smooth blood flow slowed down, sputum disappeared, treatment of TIA with calcium antagonists is effective, also supports vasospasm.

Neck arterial compression (5%):

Mainly the vertebral-basal artery insufficiency, vertebral atherosclerosis, arterial distortion, stenosis, combined with cervical spondylosis, especially sudden head or overextension, can press the vertebral artery to appear TIA, in addition, some congenital malformations; If the occipital macropores are deformed, the atlantoaxial subluxation can also cause symptoms of insufficient blood supply to the brain when the head is overactive.

Blood composition changes (5%):

Various effects on blood oxygen, blood sugar, blood lipids, blood protein content, blood viscosity and coagulative blood composition changes and blood pathological conditions, such as severe anemia, polycythemia, leukemia, thrombocytopenia, abnormal proteinemia, high Lipoproteinemia, etc., may be the trigger for TIA attacks.

Other (10%):

Cardiac dysfunction and various arrhythmias, myocardial infarction, myocarditis or infective endocarditis, air, fat, defoaming agents and other emboli caused by cardiovascular surgery, heart failure leading to pulmonary congestion, thrombosis, emboli, etc. Can lead to TIA.

None of the above several theories can explain the occurrence of all TIAs. Different cases have different pathogenesis. It is not excluded that the lesions may be located in the brain microcirculation system, which accounts for 80% to 90% of the cerebral vascular bed. However, it cannot be displayed on cerebral angiography.

Prevention

Elderly patients with transient ischemic attack prevention

Although the cause of TIA is not fully understood, most patients have hyperlipidemia, heart disease, hypertension and hyperviscosity before the disease, and cervical spondylosis, various arrhythmia, heart failure and other elderly patients are susceptible to TIA, so the first grade Prevention should focus on prevention and treatment of the above-mentioned diseases, regular review to prevent premature TIA, timely detection of patients with existing TIA attacks or prognosis, early diagnosis, early treatment, ie secondary prevention, this work is particularly important, TIA is easy to develop According to the investigation of 1987, a total of 15,854 patients with cerebrovascular disease (including TIA), including 869 cases of cerebral infarction diagnosed by CT on the head, cerebral hemorrhage Of the 313 patients, TIA was found to be an important risk factor for cerebral infarction (OR=13). Patients with a history of TIA had a 13-fold chance of having a cerebral infarction without a TIA control group, and were also a risk factor for cerebral hemorrhage (OR=4.6). The patient with a history of TIA is 4.6 times more likely to have cerebral hemorrhage than the normal elderly. Therefore, early diagnosis and proper treatment of TIA is a key and important part of prevention and treatment of stroke in the prevention and treatment of acute cerebrovascular disease. Stroke disease You should seek medical advice promptly, and restrict the development of permanent and severe disability after mild disability or defect, that is, tertiary prevention. At the same time of drug treatment, rehabilitation treatment is adopted to achieve the purpose of prevention of grade III. The goal of rehabilitation is to pass Physical therapy, comprehensive therapy based on occupational therapy, maximally promote dysfunction recovery, prevent disuse and misuse of syndromes, reduce sequelae; fully strengthen and exert residual functions, through compensation and use of auxiliary tools, and living environment Reconstruction, etc., in order to strive for patients to achieve self-care and return to society.

Complication

Complications of transient ischemic attack in the elderly Complications aphasia

Complications are rare, but there is a transient aphasia, blindness, and the possibility of a complete stroke.

Symptom

Symptoms of transient ischemic attack in the elderly Common symptoms Monocular blindness Visual impairment Falling episodes Tinnitus vertigo Dysphagia Blood changes Sensory disorder Double vision ataxia

Symptom

TIA occurs in middle-aged and elderly people (50-70 years old), males are more than females, sudden onset, rapid localized neurological function or retinal dysfunction, peaking more than 5 minutes, short duration, rapid recovery, no sequelae It can be recurrent, the symptoms are relatively constant; usually do not manifest as symptoms, only a few seconds to disappear the flash-like episodes, often have a history of hypertension, diabetes, heart and hyperlipidemia.

(1) Internal carotid artery system TIA:

1 common symptoms: the most common with paroxysmal or single-limb palsy, sputum usually upper limbs, heavier face, is the ischemic manifestation of the middle cerebral artery blood supply area or the middle cerebral artery and the anterior cerebral cortex branch.

2 characteristic symptoms:

A. Short-term blindness of one eye, but not common, cross-exclusion of the ophthalmic artery (single-sided monocular ocular blackness or blindness, contralateral hemiplegia and sensory disturbance).

B. Carotid ischemia on the primary side (usually the left side) can be aphasia.

3 symptoms may appear:

A. Symptoms of the contralateral limb or half body (performance of the middle cerebral artery blood supply area).

B. contralateral unilateral hemianopia, less common (brain middle cerebral artery and posterior cerebral artery cortex or anterior cerebral artery, middle artery, posterior artery cortex branch watershed area ischemia, and caused by the involvement of the top, pillow, and sacral junction areas ), short-term mental symptoms and disturbances of consciousness are also visible.

(2) vertebral-basal artery system TIA:

1 common symptoms: dizziness, balance disorders, most are not accompanied by tinnitus, for the vestibular ischemia of the brain stem, a small number can be associated with tinnitus, internal auditory arterial ischemia leads to inner ear involvement.

2 characteristic symptoms:

A. Drop attack: When the patient turns his head or looks up, the lower limb suddenly loses tension and falls, unconsciously lost, and is caused by ischemia of the lower brainstem reticular structure.

B. Transient global amnesia (TGA): Sudden transient memory loss, immediate memory and far memory retention, self-knowledge and personality preservation, conversation, writing, and computational power are good, seizures last for several minutes Sudden recovery in a few hours, can completely restore memory; only the experience of the episode can not be recalled, most of them are thought to be caused by the posterior cerebral artery occlusion and the limbic system of the hippocampus, hippocampus and Qianlong.

C. Binocular visual acuity episode: It is the optic cortex involvement of the occipital lobe caused by bilateral posterior cerebral artery ischemia, causing transient skin blindness.

3 possible symptoms:

A. Dysphagia, unclear articulation: manifestations of bulbar palsy or pseudobulbaric paralysis caused by brain stem ischemia.

B. Ataxia: caused by involvement of the cerebellar artery branch.

C. Consciousness disorder with or without pupil dilation: is caused by high brainstem reticular formation ischemia and reticular activation system and sympathetic descending fibers (connected fibers from the hypothalamic sympathetic zone to the spinal ciliary center).

D. One or both sides, perioral numbness or cross-sensory disturbance: is the trigeminal nucleus and the ipsilateral spinal cord thalamic ischemic manifestations.

E. Extraocular muscle paralysis and diplopia: for midbrain or pons ischemia.

2. Signs

The TIA has a short onset time, and the typical signs appear to be transient and quickly disappear. Typical signs:

(1) Internal carotid artery system: the paralyzed paralysis of the contralateral limbs, positive pathological reflex, Horner's sign crossover (Horner's sign on the lesion side, contralateral hemiplegia).

(2) vertebral-basal artery system: cross-sectional sputum, is a typical manifestation of one-sided brain stem ischemia, may have different syndromes and signs due to different parts of brain stem ischemia, such as one side of the oculomotor nerve, the nerve And/or facial nerve paralysis, contralateral limb paralysis.

Examine

Examination of transient cerebral ischemic attacks in the elderly

Laboratory examination: blood routine, blood biochemical examination is generally normal, if there is diabetes, hyperlipidemia, there may be corresponding biochemical changes.

1. Video room inspection

(1) CT and MRI examination: TIA patients were mostly normal by CT or MRI. Some cases were found to have cerebral infarction. A considerable number of infarcts were not consistent with the symptoms, and there were still old lesions. Diffusion-weighted MRI or PET showed flaky ischemia. Area.

(2) Single photo-emission computed tomography (SPECT): This test uses a single photon emitted from a radionuclide injected into the human body as a source of radiation, due to the concentration of concentrated radionuclides in different tissues. Different, and constitute different images, general SPECT can be found abnormal in the TIA attack and remission period.

(3) cerebral angiography (CAG) and digital angiography (DSA): This is a case of stenosis or obstruction of the extracranial segment of the carotid system by B-mode Doppler tomography or TCD, and TIA attacks frequently consider surgery. , this check can be performed.

(4) cervical X-ray examination: used to confirm the diagnosis of cervical spondylosis, can be taken according to the neck double oblique slice.

2. Electric examination room inspection

(1) Electroencephalogram (EEG): Basically normal.

(2) Transcranial Doppler scan (TCP) and type B real-time Doppler tomography: can understand the degree of vascular stenosis and arteriosclerosis, TCD microemboli monitoring for patients with frequent TTA, B-type real-time Doppler fault Scanning can detect the common carotid artery, arteriosclerosis such as the common carotid bifurcation and internal carotid artery.

Diagnosis

Diagnosis and diagnosis of transient ischemic attack in the elderly

Diagnostic criteria

1. Transient, reversible, local cerebral blood circulation disorder, recurrent, from 1 to 2 times, up to dozens of times, mostly related to atherosclerosis, can also be a pre-onset of cerebral infarction.

2. Can be expressed as symptoms and signs of the internal carotid artery system and / or vertebral-basal artery system.

3. The duration of each episode usually lasts from a few minutes to about 1 hour, and the symptoms and signs should disappear completely within 24 hours.

Differential diagnosis

Partial epilepsy

Symptoms, convulsions, symptoms often expand according to the cortical functional area, EEG can have localized abnormal epileptic discharge, head CT or MRI can find local lesions in the brain, anti-epileptic treatment is effective.

2. Meniere syndrome

The main cause of vertigo is confusion with the TIA of the vertebral-basal artery system, but the patient is younger, has a long episode, is often accompanied by tinnitus, hearing loss after multiple episodes, and even deafness, without signs of brain stem positioning.

Migraine

Young people are more common, characterized by recurrent pulsatile headaches, often accompanied by nausea, vomiting, visual aura before the attack, and sometimes dyskinesia and mood changes, the duration of the attack can exceed 24h.

4. Syncope

After the level of the upright position, the face is pale, cold sweat, loss of consciousness, pulse is fine, blood pressure drops, when the patient's body is level, the pulse can be powerful, the complexion turns red, the consciousness recovers, and there are many reasons. It is associated with increased vagal excitability, orthostatic hypotension or strong emotional factors.

5. Heart disease

Patients with cerebral arteriosclerosis with coronary atherosclerotic heart disease, arrhythmia, myocardial infarction with hypotension, heart failure, etc. can be confused with transient ischemic attack, but only pay attention to pulse, blood pressure, heart condition and An electrocardiogram is easy to diagnose.

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