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Transient Ischemic Attack (TIA)

Transient ischemic attack (TIA) is a temporary episode of neurologic dysfunction caused by ischemia Ischemia A hypoperfusion of the blood through an organ or tissue caused by a pathologic constriction or obstruction of its blood vessels, or an absence of blood circulation. Ischemic Cell Damage without infarction that resolves completely when blood supply is restored. Transient ischemic attack is a neurologic emergency that warrants urgent medical attention Attention Focusing on certain aspects of current experience to the exclusion of others. It is the act of heeding or taking notice or concentrating. Psychiatric Assessment. A “tissue-based” definition is currently used rather than the former time-based limit Limit A value (e.g., pressure or time) that should not be exceeded and which is specified by the operator to protect the lung Invasive Mechanical Ventilation of symptoms lasting less than 24 hours. The causes of TIA may be small clots or thromboemboli imposed on a blood vessel compromised by atherosclerosis Atherosclerosis Atherosclerosis is a common form of arterial disease in which lipid deposition forms a plaque in the blood vessel walls. Atherosclerosis is an incurable disease, for which there are clearly defined risk factors that often can be reduced through a change in lifestyle and behavior of the patient. Atherosclerosis, inflammation Inflammation Inflammation is a complex set of responses to infection and injury involving leukocytes as the principal cellular mediators in the body's defense against pathogenic organisms. Inflammation is also seen as a response to tissue injury in the process of wound healing. The 5 cardinal signs of inflammation are pain, heat, redness, swelling, and loss of function. Inflammation, or amyloid; inadequate cerebral blood flow Blood flow Blood flow refers to the movement of a certain volume of blood through the vasculature over a given unit of time (e.g., mL per minute). Vascular Resistance, Flow, and Mean Arterial Pressure from vasoconstriction Vasoconstriction The physiological narrowing of blood vessels by contraction of the vascular smooth muscle. Vascular Resistance, Flow, and Mean Arterial Pressure; or severe hypotension Hypotension Hypotension is defined as low blood pressure, specifically < 90/60 mm Hg, and is most commonly a physiologic response. Hypotension may be mild, serious, or life threatening, depending on the cause. Hypotension. The clinical presentation Presentation The position or orientation of the fetus at near term or during obstetric labor, determined by its relation to the spine of the mother and the birth canal. The normal position is a vertical, cephalic presentation with the fetal vertex flexed on the neck. Normal and Abnormal Labor includes transient neurologic deficits Neurologic Deficits High-Risk Headaches that resolve spontaneously. Management includes the reduction of risk factors to decrease the risk of a future stroke.

Last updated: Aug 13, 2021

Editorial responsibility: Stanley Oiseth, Lindsay Jones, Evelin Maza

Overview

Definition

A transient ischemic attack (TIA) is a temporary episode of neurologic dysfunction caused by ischemia Ischemia A hypoperfusion of the blood through an organ or tissue caused by a pathologic constriction or obstruction of its blood vessels, or an absence of blood circulation. Ischemic Cell Damage without infarction that resolves completely when blood supply is restored.

Epidemiology

  • Difficult to determine due to other mimicking disorders
  • Incidence Incidence The number of new cases of a given disease during a given period in a specified population. It also is used for the rate at which new events occur in a defined population. It is differentiated from prevalence, which refers to all cases in the population at a given time. Measures of Disease Frequency: approximately 500,000 cases per year in the US
  • The estimated overall prevalence Prevalence The total number of cases of a given disease in a specified population at a designated time. It is differentiated from incidence, which refers to the number of new cases in the population at a given time. Measures of Disease Frequency of TIA in the US is 2%.

Etiology

  • Thrombosis Thrombosis Formation and development of a thrombus or blood clot in the blood vessel. Epidemic Typhus with rupture of atherosclerotic plaques
  • Emboli from cardiac Cardiac Total Anomalous Pulmonary Venous Return (TAPVR) sources:
    • Left atrial thrombi/ atrial fibrillation Atrial fibrillation Atrial fibrillation (AF or Afib) is a supraventricular tachyarrhythmia and the most common kind of arrhythmia. It is caused by rapid, uncontrolled atrial contractions and uncoordinated ventricular responses. Atrial Fibrillation
    • Left ventricular thrombi
    • Rheumatic mitral or aortic valve Aortic valve The valve between the left ventricle and the ascending aorta which prevents backflow into the left ventricle. Heart: Anatomy disease
    • Bioprosthetic and mechanical heart valve emboli
    • Carotid atherosclerosis Atherosclerosis Atherosclerosis is a common form of arterial disease in which lipid deposition forms a plaque in the blood vessel walls. Atherosclerosis is an incurable disease, for which there are clearly defined risk factors that often can be reduced through a change in lifestyle and behavior of the patient. Atherosclerosis
    • Bacterial endocarditis Bacterial endocarditis Inflammation of the endocardium caused by bacteria that entered the bloodstream. The strains of bacteria vary with predisposing factors, such as congenital heart defects; heart valve diseases; heart valve prosthesis implantation; or intravenous drug use. Endocarditis (septic emboli)
    • Patent foramen ovale Foramen ovale An opening in the wall between the right and the left upper chambers (heart atria) of a fetal heart. Oval foramen normally closes soon after birth; when it fails to close the condition is called patent oval foramen. Patent Foramen Ovale
    • Arterial dissection Arterial dissection Arterial dissection is a violation of the structural integrity of the arterial wall that results in blood accumulating between the layers. Dissection of the Carotid and Vertebral Arteries (rupture of an arterial wall followed by thrombus formation and embolization Embolization A method of hemostasis utilizing various agents such as gelfoam, silastic, metal, glass, or plastic pellets, autologous clot, fat, and muscle as emboli. It has been used in the treatment of spinal cord and intracranial arteriovenous malformations, renal arteriovenous fistulas, gastrointestinal bleeding, epistaxis, hypersplenism, certain highly vascular tumors, traumatic rupture of blood vessels, and control of operative hemorrhage. Gastrointestinal Bleeding)
  • Atherosclerosis Atherosclerosis Atherosclerosis is a common form of arterial disease in which lipid deposition forms a plaque in the blood vessel walls. Atherosclerosis is an incurable disease, for which there are clearly defined risk factors that often can be reduced through a change in lifestyle and behavior of the patient. Atherosclerosis may also be embolic (in addition to thrombotic):
    • Iatrogenic Iatrogenic Any adverse condition in a patient occurring as the result of treatment by a physician, surgeon, or other health professional, especially infections acquired by a patient during the course of treatment. Anterior Cord Syndrome embolization Embolization A method of hemostasis utilizing various agents such as gelfoam, silastic, metal, glass, or plastic pellets, autologous clot, fat, and muscle as emboli. It has been used in the treatment of spinal cord and intracranial arteriovenous malformations, renal arteriovenous fistulas, gastrointestinal bleeding, epistaxis, hypersplenism, certain highly vascular tumors, traumatic rupture of blood vessels, and control of operative hemorrhage. Gastrointestinal Bleeding after an angiogram or other vascular procedures
    • Emboli released during carotid artery surgery

Risk factors

  • Hypertension Hypertension Hypertension, or high blood pressure, is a common disease that manifests as elevated systemic arterial pressures. Hypertension is most often asymptomatic and is found incidentally as part of a routine physical examination or during triage for an unrelated medical encounter. Hypertension (most important)
  • Previous history of TIA
  • Diabetes Diabetes Diabetes mellitus (DM) is a metabolic disease characterized by hyperglycemia and dysfunction of the regulation of glucose metabolism by insulin. Type 1 DM is diagnosed mostly in children and young adults as the result of autoimmune destruction of β cells in the pancreas and the resulting lack of insulin. Type 2 DM has a significant association with obesity and is characterized by insulin resistance. Diabetes Mellitus mellitus
  • Smoking Smoking Willful or deliberate act of inhaling and exhaling smoke from burning substances or agents held by hand. Interstitial Lung Diseases
  • Hyperlipidemia
  • Atrial fibrillation Atrial fibrillation Atrial fibrillation (AF or Afib) is a supraventricular tachyarrhythmia and the most common kind of arrhythmia. It is caused by rapid, uncontrolled atrial contractions and uncoordinated ventricular responses. Atrial Fibrillation
  • Carotid stenosis Stenosis Hypoplastic Left Heart Syndrome (HLHS) or other arterial stenoses
  • Patent foramen ovale Foramen ovale An opening in the wall between the right and the left upper chambers (heart atria) of a fetal heart. Oval foramen normally closes soon after birth; when it fails to close the condition is called patent oval foramen. Patent Foramen Ovale

Pathophysiology and Clinical Presentation

The presentation Presentation The position or orientation of the fetus at near term or during obstetric labor, determined by its relation to the spine of the mother and the birth canal. The normal position is a vertical, cephalic presentation with the fetal vertex flexed on the neck. Normal and Abnormal Labor depends on the pathophysiologic mechanism: embolic, lacunar (small penetrating vessel) TIA, or large artery TIA.

Pathophysiology

  • Temporary occlusion of a blood vessel (due to a small thrombus, embolus, vasoconstriction Vasoconstriction The physiological narrowing of blood vessels by contraction of the vascular smooth muscle. Vascular Resistance, Flow, and Mean Arterial Pressure, or systemic hypoperfusion Systemic Hypoperfusion Ischemic Stroke) to the brain Brain The part of central nervous system that is contained within the skull (cranium). Arising from the neural tube, the embryonic brain is comprised of three major parts including prosencephalon (the forebrain); mesencephalon (the midbrain); and rhombencephalon (the hindbrain). The developed brain consists of cerebrum; cerebellum; and other structures in the brain stem. Nervous System: Anatomy, Structure, and Classification, spinal cord Spinal cord The spinal cord is the major conduction pathway connecting the brain to the body; it is part of the CNS. In cross section, the spinal cord is divided into an H-shaped area of gray matter (consisting of synapsing neuronal cell bodies) and a surrounding area of white matter (consisting of ascending and descending tracts of myelinated axons). Spinal Cord: Anatomy, or retina Retina The ten-layered nervous tissue membrane of the eye. It is continuous with the optic nerve and receives images of external objects and transmits visual impulses to the brain. Its outer surface is in contact with the choroid and the inner surface with the vitreous body. The outermost layer is pigmented, whereas the inner nine layers are transparent. Eye: Anatomy
  • Reduction in blood flow Blood flow Blood flow refers to the movement of a certain volume of blood through the vasculature over a given unit of time (e.g., mL per minute). Vascular Resistance, Flow, and Mean Arterial Pressure to the region supplied by the vessels →
  • Cerebral or other tissues undergo ischemia Ischemia A hypoperfusion of the blood through an organ or tissue caused by a pathologic constriction or obstruction of its blood vessels, or an absence of blood circulation. Ischemic Cell Damage
  • Neurons Neurons The basic cellular units of nervous tissue. Each neuron consists of a body, an axon, and dendrites. Their purpose is to receive, conduct, and transmit impulses in the nervous system. Nervous System: Histology are deprived of glucose Glucose A primary source of energy for living organisms. It is naturally occurring and is found in fruits and other parts of plants in its free state. It is used therapeutically in fluid and nutrient replacement. Lactose Intolerance and oxygen → failure of mitochondria Mitochondria Semiautonomous, self-reproducing organelles that occur in the cytoplasm of all cells of most, but not all, eukaryotes. Each mitochondrion is surrounded by a double limiting membrane. The inner membrane is highly invaginated, and its projections are called cristae. Mitochondria are the sites of the reactions of oxidative phosphorylation, which result in the formation of ATP. They contain distinctive ribosomes, transfer RNAs; amino Acyl tRNA synthetases; and elongation and termination factors. Mitochondria depend upon genes within the nucleus of the cells in which they reside for many essential messenger RNAs. Mitochondria are believed to have arisen from aerobic bacteria that established a symbiotic relationship with primitive protoeukaryotes. The Cell: Organelles to produce ATP
  • Minutes to hours later, before infarction occurs, blood flow Blood flow Blood flow refers to the movement of a certain volume of blood through the vasculature over a given unit of time (e.g., mL per minute). Vascular Resistance, Flow, and Mean Arterial Pressure is restored and all neurologic dysfunction resolves.

Clinical presentation Presentation The position or orientation of the fetus at near term or during obstetric labor, determined by its relation to the spine of the mother and the birth canal. The normal position is a vertical, cephalic presentation with the fetal vertex flexed on the neck. Normal and Abnormal Labor

The affected individual may not recall the time of onset of neurological symptoms. Establish a precise account of the event, if possible, from family members or caregivers, and include the time of onset and resolution, if the symptoms have already improved.

Symptoms of TIA relate to the vascular territory that is being compromised:

  • Internal carotid artery Internal carotid artery Branch of the common carotid artery which supplies the anterior part of the brain, the eye and its appendages, the forehead and nose. Carotid Arterial System: Anatomy and middle cerebral artery Middle cerebral artery The largest of the cerebral arteries. It trifurcates into temporal, frontal, and parietal branches supplying blood to most of the parenchyma of these lobes in the cerebral cortex. These are the areas involved in motor, sensory, and speech activities. Cerebrovascular System: Anatomy (MCA) symptoms:
    • Transient monocular blindness Blindness The inability to see or the loss or absence of perception of visual stimuli. This condition may be the result of eye diseases; optic nerve diseases; optic chiasm diseases; or brain diseases affecting the visual pathways or occipital lobe. Retinopathy of Prematurity ( amaurosis fugax Amaurosis fugax Transient complete or partial monocular blindness due to retinal ischemia. This may be caused by emboli from the carotid artery (usually in association with carotid stenosis) and other locations that enter the central retinal artery. Carotid Artery Stenosis) or hemianopia
    • Motor Motor Neurons which send impulses peripherally to activate muscles or secretory cells. Nervous System: Histology weakness in the arm Arm The arm, or “upper arm” in common usage, is the region of the upper limb that extends from the shoulder to the elbow joint and connects inferiorly to the forearm through the cubital fossa. It is divided into 2 fascial compartments (anterior and posterior). Arm: Anatomy/ hand Hand The hand constitutes the distal part of the upper limb and provides the fine, precise movements needed in activities of daily living. It consists of 5 metacarpal bones and 14 phalanges, as well as numerous muscles innervated by the median and ulnar nerves. Hand: Anatomy > leg Leg The lower leg, or just “leg” in anatomical terms, is the part of the lower limb between the knee and the ankle joint. The bony structure is composed of the tibia and fibula bones, and the muscles of the leg are grouped into the anterior, lateral, and posterior compartments by extensions of fascia. Leg: Anatomy > face
    • Milder sensory Sensory Neurons which conduct nerve impulses to the central nervous system. Nervous System: Histology loss in the same areas
    • Aphasia Aphasia A cognitive disorder marked by an impaired ability to comprehend or express language in its written or spoken form. This condition is caused by diseases which affect the language areas of the dominant hemisphere. Clinical features are used to classify the various subtypes of this condition. General categories include receptive, expressive, and mixed forms of aphasia. Ischemic Stroke and alexia (inability to interpret written language)
  • Vertebral artery Vertebral artery The first branch of the subclavian artery with distribution to muscles of the neck; vertebrae; spinal cord; cerebellum; and interior of the cerebrum. Lateral Medullary Syndrome (Wallenberg Syndrome)/basilar artery symptoms:
    • Quadriparesis
    • Crossed motor Motor Neurons which send impulses peripherally to activate muscles or secretory cells. Nervous System: Histology weakness and sensory Sensory Neurons which conduct nerve impulses to the central nervous system. Nervous System: Histology abnormalities (1 side of the cranial nerve distribution with the opposite side limbs and the trunk)
    • Gait ataxia Gait ataxia Impairment of the ability to coordinate the movements required for normal ambulation (walking) which may result from impairments of motor function or sensory feedback. This condition may be associated with brain diseases (including cerebellar diseases and basal ganglia diseases); spinal cord diseases; or peripheral nervous system diseases. Friedreich’s Ataxia
    • Brainstem and cranial nerve symptoms:  dizziness Dizziness An imprecise term which may refer to a sense of spatial disorientation, motion of the environment, or lightheadedness. Lateral Medullary Syndrome (Wallenberg Syndrome), diplopia Diplopia A visual symptom in which a single object is perceived by the visual cortex as two objects rather than one. Disorders associated with this condition include refractive errors; strabismus; oculomotor nerve diseases; trochlear nerve diseases; abducens nerve diseases; and diseases of the brain stem and occipital lobe. Myasthenia Gravis, tinnitus Tinnitus A nonspecific symptom of hearing disorder characterized by the sensation of buzzing, ringing, clicking, pulsations, and other noises in the ear. Objective tinnitus refers to noises generated from within the ear or adjacent structures that can be heard by other individuals. The term subjective tinnitus is used when the sound is audible only to the affected individual. Tinnitus may occur as a manifestation of cochlear diseases; vestibulocochlear nerve diseases; intracranial hypertension; craniocerebral trauma; and other conditions. Cranial Nerve Palsies
  • Posterior cerebral artery Posterior cerebral artery Artery formed by the bifurcation of the basilar artery. Branches of the posterior cerebral artery supply portions of the occipital lobe; parietal lobe; inferior temporal gyrus, brainstem, and choroid plexus. Cerebrovascular System: Anatomy (PCA):
    • Hemianopia/ blindness Blindness The inability to see or the loss or absence of perception of visual stimuli. This condition may be the result of eye diseases; optic nerve diseases; optic chiasm diseases; or brain diseases affecting the visual pathways or occipital lobe. Retinopathy of Prematurity
    • Hemisensory loss in the arm Arm The arm, or “upper arm” in common usage, is the region of the upper limb that extends from the shoulder to the elbow joint and connects inferiorly to the forearm through the cubital fossa. It is divided into 2 fascial compartments (anterior and posterior). Arm: Anatomy/ hand Hand The hand constitutes the distal part of the upper limb and provides the fine, precise movements needed in activities of daily living. It consists of 5 metacarpal bones and 14 phalanges, as well as numerous muscles innervated by the median and ulnar nerves. Hand: Anatomy > leg Leg The lower leg, or just “leg” in anatomical terms, is the part of the lower limb between the knee and the ankle joint. The bony structure is composed of the tibia and fibula bones, and the muscles of the leg are grouped into the anterior, lateral, and posterior compartments by extensions of fascia. Leg: Anatomy or face
    • Amnesia
    • Alexia
  • Lacunar infarcts:
    • Hemiparesis Hemiparesis The term hemiparesis refers to mild to moderate weakness involving one side of the body. Epidural Hemorrhage
    • Hemisensory loss in the face > arm Arm The arm, or “upper arm” in common usage, is the region of the upper limb that extends from the shoulder to the elbow joint and connects inferiorly to the forearm through the cubital fossa. It is divided into 2 fascial compartments (anterior and posterior). Arm: Anatomy or leg Leg The lower leg, or just “leg” in anatomical terms, is the part of the lower limb between the knee and the ankle joint. The bony structure is composed of the tibia and fibula bones, and the muscles of the leg are grouped into the anterior, lateral, and posterior compartments by extensions of fascia. Leg: Anatomy
    • Limb ataxia Ataxia Impairment of the ability to perform smoothly coordinated voluntary movements. This condition may affect the limbs, trunk, eyes, pharynx, larynx, and other structures. Ataxia may result from impaired sensory or motor function. Sensory ataxia may result from posterior column injury or peripheral nerve diseases. Motor ataxia may be associated with cerebellar diseases; cerebral cortex diseases; thalamic diseases; basal ganglia diseases; injury to the red nucleus; and other conditions. Ataxia-telangiectasia/weakness
    • Mild dysarthria Dysarthria Disorders of speech articulation caused by imperfect coordination of pharynx, larynx, tongue, or face muscles. This may result from cranial nerve diseases; neuromuscular diseases; cerebellar diseases; basal ganglia diseases; brain stem diseases; or diseases of the corticobulbar tracts. The cortical language centers are intact in this condition. Wilson’s Disease and dysphagia Dysphagia Dysphagia is the subjective sensation of difficulty swallowing. Symptoms can range from a complete inability to swallow, to the sensation of solids or liquids becoming “stuck.” Dysphagia is classified as either oropharyngeal or esophageal, with esophageal dysphagia having 2 sub-types: functional and mechanical. Dysphagia
  • Atypical TIA symptoms:
    • Gradual increase in symptoms over > 5 minutes
    • Progression of symptoms from 1 body part to another
    • Isolated visual disturbances (e.g., flashing lights)
    • Isolated sensory Sensory Neurons which conduct nerve impulses to the central nervous system. Nervous System: Histology symptoms (e.g., in a finger or the tongue Tongue The tongue, on the other hand, is a complex muscular structure that permits tasting and facilitates the process of mastication and communication. The blood supply of the tongue originates from the external carotid artery, and the innervation is through cranial nerves. Lips and Tongue: Anatomy)
    • Isolated brainstem symptoms (e.g., dysarthria Dysarthria Disorders of speech articulation caused by imperfect coordination of pharynx, larynx, tongue, or face muscles. This may result from cranial nerve diseases; neuromuscular diseases; cerebellar diseases; basal ganglia diseases; brain stem diseases; or diseases of the corticobulbar tracts. The cortical language centers are intact in this condition. Wilson’s Disease, diplopia Diplopia A visual symptom in which a single object is perceived by the visual cortex as two objects rather than one. Disorders associated with this condition include refractive errors; strabismus; oculomotor nerve diseases; trochlear nerve diseases; abducens nerve diseases; and diseases of the brain stem and occipital lobe. Myasthenia Gravis, or hearing loss Hearing loss Hearing loss, also known as hearing impairment, is any degree of impairment in the ability to apprehend sound as determined by audiometry to be below normal hearing thresholds. Clinical presentation may occur at birth or as a gradual loss of hearing with age, including a short-term or sudden loss at any point. Hearing Loss)

Diagnosis

Since the etiologies for stroke and TIA are very similar, the diagnostic evaluation for TIA resembles that for ischemic stroke Ischemic Stroke An ischemic stroke (also known as cerebrovascular accident) is an acute neurologic injury that occurs as a result of brain ischemia; this condition may be due to cerebral blood vessel occlusion by thrombosis or embolism, or rarely due to systemic hypoperfusion. Ischemic Stroke.

  • History as above; always ask about:
    • Past episodes of TIA
    • Medications
    • Cardiovascular risk factors
    • Prior carotid or heart surgeries
  • Physical examination:
    • Neurologic symptoms may have been resolved by the time the affected individual arrives at the ED.
    • Vital signs and simultaneous point-of-care glucose Glucose A primary source of energy for living organisms. It is naturally occurring and is found in fruits and other parts of plants in its free state. It is used therapeutically in fluid and nutrient replacement. Lactose Intolerance
    • General exam including cardiac Cardiac Total Anomalous Pulmonary Venous Return (TAPVR) exam
    • Detailed neurological exam as much as feasible:
      • Signs and symptoms depend on the vascular territory affected.
      • Affected individuals may exhibit some degree of memory Memory Complex mental function having four distinct phases: (1) memorizing or learning, (2) retention, (3) recall, and (4) recognition. Clinically, it is usually subdivided into immediate, recent, and remote memory. Psychiatric Assessment loss or amnesia of the events.
  • Labs:
    • CBC including platelet count
    • Chemistry: electrolytes Electrolytes Electrolytes are mineral salts that dissolve in water and dissociate into charged particles called ions, which can be either be positively (cations) or negatively (anions) charged. Electrolytes are distributed in the extracellular and intracellular compartments in different concentrations. Electrolytes are essential for various basic life-sustaining functions. Electrolytes, glucose Glucose A primary source of energy for living organisms. It is naturally occurring and is found in fruits and other parts of plants in its free state. It is used therapeutically in fluid and nutrient replacement. Lactose Intolerance, BUN, and creatinine
    • Serum lipid profile Lipid profile Lipid Disorders provides a baseline but may not be accurate in an acute emergency situation.
    • PT and PTT
    • Cardiac Cardiac Total Anomalous Pulmonary Venous Return (TAPVR) enzymes Enzymes Enzymes are complex protein biocatalysts that accelerate chemical reactions without being consumed by them. Due to the body’s constant metabolic needs, the absence of enzymes would make life unsustainable, as reactions would occur too slowly without these molecules. Basics of Enzymes
    • Direct factor Xa activity assay: if the affected individual is taking a direct thrombin inhibitor Direct Thrombin Inhibitor Anticoagulants or direct factor Xa inhibitor Direct Factor Xa Inhibitor Anticoagulants and is a candidate for thrombolytic therapy
    • Urinalysis Urinalysis Examination of urine by chemical, physical, or microscopic means. Routine urinalysis usually includes performing chemical screening tests, determining specific gravity, observing any unusual color or odor, screening for bacteriuria, and examining the sediment microscopically. Urinary Tract Infections (UTIs) in Children
  • Other tests: ECG ECG An electrocardiogram (ECG) is a graphic representation of the electrical activity of the heart plotted against time. Adhesive electrodes are affixed to the skin surface allowing measurement of cardiac impulses from many angles. The ECG provides 3-dimensional information about the conduction system of the heart, the myocardium, and other cardiac structures. Electrocardiogram (ECG) for arrhythmia or ischemic changes
  • Imaging:
    • Noncontrast head CT:
      • Only for differentiation between ischemic and hemorrhagic strokes
      • Acute ischemic zones are NOT visualized (can be mistaken for a normal scan).
      • Preferred emergency imaging modality
    • MRI brain Brain The part of central nervous system that is contained within the skull (cranium). Arising from the neural tube, the embryonic brain is comprised of three major parts including prosencephalon (the forebrain); mesencephalon (the midbrain); and rhombencephalon (the hindbrain). The developed brain consists of cerebrum; cerebellum; and other structures in the brain stem. Nervous System: Anatomy, Structure, and Classification:
      • Allows visualization of acute ischemia Ischemia A hypoperfusion of the blood through an organ or tissue caused by a pathologic constriction or obstruction of its blood vessels, or an absence of blood circulation. Ischemic Cell Damage and ischemic penumbra Ischemic Penumbra Ischemic Stroke = greater sensitivity Sensitivity Binary classification measures to assess test results. Sensitivity or recall rate is the proportion of true positives. Blotting Techniques
      • Better resolution but longer time for imaging
      • Less availability
    • Carotid ultrasonography or transcranial Doppler Doppler Ultrasonography applying the doppler effect, with frequency-shifted ultrasound reflections produced by moving targets (usually red blood cells) in the bloodstream along the ultrasound axis in direct proportion to the velocity of movement of the targets, to determine both direction and velocity of blood flow. Ultrasound (Sonography) ultrasonography: to evaluate for atherosclerotic stenosis Stenosis Hypoplastic Left Heart Syndrome (HLHS) or aneurysms
    • Echocardiogram Echocardiogram Transposition of the Great Vessels/transesophageal echocardiogram Echocardiogram Transposition of the Great Vessels: to detect structural abnormalities that could facilitate embolization Embolization A method of hemostasis utilizing various agents such as gelfoam, silastic, metal, glass, or plastic pellets, autologous clot, fat, and muscle as emboli. It has been used in the treatment of spinal cord and intracranial arteriovenous malformations, renal arteriovenous fistulas, gastrointestinal bleeding, epistaxis, hypersplenism, certain highly vascular tumors, traumatic rupture of blood vessels, and control of operative hemorrhage. Gastrointestinal Bleeding
      • Patent foramen ovale Foramen ovale An opening in the wall between the right and the left upper chambers (heart atria) of a fetal heart. Oval foramen normally closes soon after birth; when it fails to close the condition is called patent oval foramen. Patent Foramen Ovale
      • Atrial septal defect Atrial Septal Defect Atrial septal defects (ASDs) are benign acyanotic congenital heart defects characterized by an opening in the interatrial septum that causes blood to flow from the left atrium (LA) to the right atrium (RA) (left-to-right shunt). Atrial Septal Defect (ASD)
      • Clots in the atria or ventricles
Axial cut of a ct scan of a patient with acute ischemic stroke

Axial Axial Computed Tomography (CT) cut of a CT scan of an individual with acute ischemic stroke Ischemic Stroke An ischemic stroke (also known as cerebrovascular accident) is an acute neurologic injury that occurs as a result of brain ischemia; this condition may be due to cerebral blood vessel occlusion by thrombosis or embolism, or rarely due to systemic hypoperfusion. Ischemic Stroke performed at the time of admission:
Note the lack of discernible changes.

Image: “Pseudoradial Nerve Palsy Palsy paralysis of an area of the body, thus incapable of voluntary movement Cranial Nerve Palsies Caused by Acute Ischemic Stroke Ischemic Stroke An ischemic stroke (also known as cerebrovascular accident) is an acute neurologic injury that occurs as a result of brain ischemia; this condition may be due to cerebral blood vessel occlusion by thrombosis or embolism, or rarely due to systemic hypoperfusion. Ischemic Stroke” by Tahir H, Daruwalla V, Meisel J, Kodsi SE. License: CC BY 3.0

Management

Initial management

  • Assess the individual’s airway Airway ABCDE Assessment, breathing, and circulation Circulation The movement of the blood as it is pumped through the cardiovascular system. ABCDE Assessment (ABC).
  • Treat hypoglycemia Hypoglycemia Hypoglycemia is an emergency condition defined as a serum glucose level ≤ 70 mg/dL (≤ 3.9 mmol/L) in diabetic patients. In nondiabetic patients, there is no specific or defined limit for normal serum glucose levels, and hypoglycemia is defined mainly by its clinical features. Hypoglycemia or hyperglycemia Hyperglycemia Abnormally high blood glucose level. Diabetes Mellitus accordingly (may mimic TIA or stroke).
  • IV fluids IV fluids Intravenous fluids are one of the most common interventions administered in medicine to approximate physiologic bodily fluids. Intravenous fluids are divided into 2 categories: crystalloid and colloid solutions. Intravenous fluids have a wide variety of indications, including intravascular volume expansion, electrolyte manipulation, and maintenance fluids. Intravenous Fluids
  • ABCD2 score = stroke risk stratification
    • Predicts stroke risk in the next 2 days, 7 days, and 90 days
    • Consider hospitalization Hospitalization The confinement of a patient in a hospital. Delirium if the score is ≥ 4.
    • Age ≥ 60 years
    • Blood pressure (initial): higher risk of stroke if systolic blood pressure ≥ 140 or diastolic blood pressure ≥ 90
    • Clinical features of TIA:
      • Unilateral weakness
      • Speech disturbance without weakness
    • Duration of symptoms
    • Diabetes history
  • Consider thrombolytic therapy if TIA evolves to a diagnosis of stroke.

Prevention of future TIAs and stroke

  • Lifestyle changes:
    • Healthy diet (e.g., Mediterranean diet)
    • Exercise as tolerated, consider weight loss if obese
    • Smoking cessation counseling, if applicable
  • Risk-factor management with improved control of:
    • Diabetes
    • Hypertension
    • Hyperlipidemia
  • Medications:
    • Antiplatelet therapy unless contraindicated:
      • Aspirin
      • Clopidogrel or extended-release dipyridamole if unable to take aspirin
    • Statins (e.g., atorvastatin) in clinically important atherosclerotic disease
    • Anticoagulants, if indicated for atrial fibrillation or coagulation disorder
  • Treat the underlying causes.
  • Surgery (carotid endarterectomy):
    • If workup reveals symptomatic internal carotid artery stenosis > 70%
    • Benefits of surgery must outweigh the risks, which also include stroke.
  • Family and patient education:
    • Continuation of preventive measures at home 
    • The “FAST” mnemonic is helpful for lay individuals to identify the recurrence of TIAs:
      • Facial droop
      • Arm weakness
      • Speech abnormality
      • Time

Prognosis Prognosis A prediction of the probable outcome of a disease based on a individual’s condition and the usual course of the disease as seen in similar situations. Non-Hodgkin Lymphomas

  • TIA is a prognostic indicator Indicator Methods for assessing flow through a system by injection of a known quantity of an indicator, such as a dye, radionuclide, or chilled liquid, into the system and monitoring its concentration over time at a specific point in the system. Body Fluid Compartments of stroke.
  • 50% risk of stroke within the 1st 2 days after symptom onset
  • 10%–15% risk of stroke in the 1st 3 months
  • 5%–6% annual mortality Mortality All deaths reported in a given population. Measures of Health Status rate after TIA

Differential Diagnosis

  • Ischemic (or hemorrhagic) stroke ( cerebrovascular accident Cerebrovascular accident An ischemic stroke (also known as cerebrovascular accident) is an acute neurologic injury that occurs as a result of brain ischemia; this condition may be due to cerebral blood vessel occlusion by thrombosis or embolism, or rarely due to systemic hypoperfusion. Ischemic Stroke): an acute neurologic injury resulting from brain ischemia Brain Ischemia Localized reduction of blood flow to brain tissue due to arterial obstruction or systemic hypoperfusion. This frequently occurs in conjunction with brain hypoxia. Prolonged ischemia is associated with brain infarction. Ischemic Stroke, which may be due to cerebral blood vessel occlusion by thrombosis Thrombosis Formation and development of a thrombus or blood clot in the blood vessel. Epidemic Typhus or embolism. The clinical presentation Presentation The position or orientation of the fetus at near term or during obstetric labor, determined by its relation to the spine of the mother and the birth canal. The normal position is a vertical, cephalic presentation with the fetal vertex flexed on the neck. Normal and Abnormal Labor includes neurologic symptoms with varying degrees of motor Motor Neurons which send impulses peripherally to activate muscles or secretory cells. Nervous System: Histology and sensory Sensory Neurons which conduct nerve impulses to the central nervous system. Nervous System: Histology loss. Diagnosis is made by physical examination and imaging. Management is ideally with thrombolytic therapy. Long-term rehabilitation with PT is important after the acute event.
  • Migraine Migraine Migraine headache is a primary headache disorder and is among the most prevalent disorders in the world. Migraine is characterized by episodic, moderate to severe headaches that may be associated with increased sensitivity to light and sound, as well as nausea and/or vomiting. Migraine Headache: a common primary headache Headache The symptom of pain in the cranial region. It may be an isolated benign occurrence or manifestation of a wide variety of headache disorders. Brain Abscess disorder characterized by episodic, moderate-to-severe headaches that may be associated with increased sensitivity Sensitivity Binary classification measures to assess test results. Sensitivity or recall rate is the proportion of true positives. Blotting Techniques to light and sound, and nausea Nausea An unpleasant sensation in the stomach usually accompanied by the urge to vomit. Common causes are early pregnancy, sea and motion sickness, emotional stress, intense pain, food poisoning, and various enteroviruses. Antiemetics and/or vomiting Vomiting The forcible expulsion of the contents of the stomach through the mouth. Hypokalemia. Migraines with aura Aura Reversible neurological phenomena that often precede or coincide with headache onset. Migraine Headache may be indistinguishable from TIA due to vasoconstriction Vasoconstriction The physiological narrowing of blood vessels by contraction of the vascular smooth muscle. Vascular Resistance, Flow, and Mean Arterial Pressure, which causes ischemia Ischemia A hypoperfusion of the blood through an organ or tissue caused by a pathologic constriction or obstruction of its blood vessels, or an absence of blood circulation. Ischemic Cell Damage and neurologic deficits Neurologic Deficits High-Risk Headaches similar to an ischemic stroke Ischemic Stroke An ischemic stroke (also known as cerebrovascular accident) is an acute neurologic injury that occurs as a result of brain ischemia; this condition may be due to cerebral blood vessel occlusion by thrombosis or embolism, or rarely due to systemic hypoperfusion. Ischemic Stroke, including hemiplegia. Diagnosis is based on clinical history, physical exam, and imaging findings. Management includes medications to treat migraines and the avoidance of triggers Triggers Hereditary Angioedema (C1 Esterase Inhibitor Deficiency).
  • Intracranial tumor Tumor Inflammation: can be a primary neoplasm derived from intracranial tissues ( astrocytoma Astrocytoma Astrocytomas are neuroepithelial tumors that arise from astrocytes, which are star-shaped glial cells (supporting tissues of the CNS). Astrocytomas are a type of glioma. There are 4 grades of astrocytomas. Astrocytoma, oligodendroglioma Oligodendroglioma Oligodendrogliomas are malignant CNS tumors arising from neural glial cell precursors. Oligodendrogliomas often arise in the frontal lobes of the brain and have a generally favorable prognosis when compared to other gliomas. Oligodendrogliomas are the 3rd most common CNS tumor. The most frequent presenting symptom is a seizure. Oligodendroglioma, meningioma Meningioma Meningiomas are slow-growing tumors that arise from the meninges of the brain and spinal cord. The vast majority are benign. These tumors commonly occur in individuals with a history of high doses of skull radiation, head trauma, and neurofibromatosis 2. Meningioma) or a metastatic process from another malignancy Malignancy Hemothorax such as lung or breast cancer Breast cancer Breast cancer is a disease characterized by malignant transformation of the epithelial cells of the breast. Breast cancer is the most common form of cancer and 2nd most common cause of cancer-related death among women. Breast Cancer. As the mass Mass Three-dimensional lesion that occupies a space within the breast Imaging of the Breast grows, it can give rise to neurological symptoms similar to those seen in an ischemic stroke Ischemic Stroke An ischemic stroke (also known as cerebrovascular accident) is an acute neurologic injury that occurs as a result of brain ischemia; this condition may be due to cerebral blood vessel occlusion by thrombosis or embolism, or rarely due to systemic hypoperfusion. Ischemic Stroke. Diagnosis is based on imaging studies and management is based on addressing the underlying cause.
  • Brain abscess Brain abscess Brain abscess is a life-threatening condition that involves the collection of pus in the brain parenchyma caused by infection from bacteria, fungi, parasites, or protozoa. The most common presentation is headache, fever with chills, seizures, and neurological deficits. Brain Abscess: a life-threatening condition involving the collection of pus in the brain Brain The part of central nervous system that is contained within the skull (cranium). Arising from the neural tube, the embryonic brain is comprised of three major parts including prosencephalon (the forebrain); mesencephalon (the midbrain); and rhombencephalon (the hindbrain). The developed brain consists of cerebrum; cerebellum; and other structures in the brain stem. Nervous System: Anatomy, Structure, and Classification parenchyma due to an infection. Brain Brain The part of central nervous system that is contained within the skull (cranium). Arising from the neural tube, the embryonic brain is comprised of three major parts including prosencephalon (the forebrain); mesencephalon (the midbrain); and rhombencephalon (the hindbrain). The developed brain consists of cerebrum; cerebellum; and other structures in the brain stem. Nervous System: Anatomy, Structure, and Classification abscesses may also result from trauma or a surgical complication. The most common presentations include headache Headache The symptom of pain in the cranial region. It may be an isolated benign occurrence or manifestation of a wide variety of headache disorders. Brain Abscess, fever with chills Fever With Chills Brain Abscess, seizures Seizures A seizure is abnormal electrical activity of the neurons in the cerebral cortex that can manifest in numerous ways depending on the region of the brain affected. Seizures consist of a sudden imbalance that occurs between the excitatory and inhibitory signals in cortical neurons, creating a net excitation. The 2 major classes of seizures are focal and generalized. Seizures, and neurologic deficits Neurologic Deficits High-Risk Headaches. Diagnosis is by MRI and/or CT-guided aspiration of the contents for culture. Management requires surgical drainage and antibiotics.
  • Carotid artery aneurysm Aneurysm An aneurysm is a bulging, weakened area of a blood vessel that causes an abnormal widening of its diameter > 1.5 times the size of the native vessel. Aneurysms occur more often in arteries than in veins and are at risk of dissection and rupture, which can be life-threatening. Thoracic Aortic Aneurysms or dissection: a condition that may occur when the integrity of the arterial walls fails, usually abruptly, resulting in intramural hematoma Hematoma A collection of blood outside the blood vessels. Hematoma can be localized in an organ, space, or tissue. Intussusception formation and a false lumen False lumen Aortic Dissection leading to the formation of an aneurysm Aneurysm An aneurysm is a bulging, weakened area of a blood vessel that causes an abnormal widening of its diameter > 1.5 times the size of the native vessel. Aneurysms occur more often in arteries than in veins and are at risk of dissection and rupture, which can be life-threatening. Thoracic Aortic Aneurysms and, later, dissection. Affected individuals typically present with unilateral head or neck Neck The part of a human or animal body connecting the head to the rest of the body. Peritonsillar Abscess pain Pain An unpleasant sensation induced by noxious stimuli which are detected by nerve endings of nociceptive neurons. Pain: Types and Pathways and/or stroke-like symptoms. Dissections are confirmed based on imaging studies and are treated by medical management and, sometimes, surgical management. Complications can include cerebrovascular stroke and death in severe cases.
  • Hypoglycemia Hypoglycemia Hypoglycemia is an emergency condition defined as a serum glucose level ≤ 70 mg/dL (≤ 3.9 mmol/L) in diabetic patients. In nondiabetic patients, there is no specific or defined limit for normal serum glucose levels, and hypoglycemia is defined mainly by its clinical features. Hypoglycemia: an emergency condition characterized by a drop in glucose Glucose A primary source of energy for living organisms. It is naturally occurring and is found in fruits and other parts of plants in its free state. It is used therapeutically in fluid and nutrient replacement. Lactose Intolerance levels to < 55 mg/dL (3 mmol/L), although the specific values vary among and within individuals over time. The clinical presentations of hypoglycemia Hypoglycemia Hypoglycemia is an emergency condition defined as a serum glucose level ≤ 70 mg/dL (≤ 3.9 mmol/L) in diabetic patients. In nondiabetic patients, there is no specific or defined limit for normal serum glucose levels, and hypoglycemia is defined mainly by its clinical features. Hypoglycemia include neuroglycopenic symptoms Neuroglycopenic Symptoms Hypoglycemia such as dizziness Dizziness An imprecise term which may refer to a sense of spatial disorientation, motion of the environment, or lightheadedness. Lateral Medullary Syndrome (Wallenberg Syndrome), confusion, lethargy Lethargy A general state of sluggishness, listless, or uninterested, with being tired, and having difficulty concentrating and doing simple tasks. It may be related to depression or drug addiction. Hyponatremia, and loss of consciousness, and can mimic a TIA or stroke. Diagnosis is based on lab testing. Management is with oral glucose Glucose A primary source of energy for living organisms. It is naturally occurring and is found in fruits and other parts of plants in its free state. It is used therapeutically in fluid and nutrient replacement. Lactose Intolerance or IV dextrose Dextrose Intravenous Fluids and depends on the severity of symptoms.

References

  1. Panuganti, K.K., Tadi, P., Lui, F. (2021). Transient ischemic attack. StatPearls. Treasure Island (FL): StatPearls Publishing. Retrieved August 5, 2021, from http://www.ncbi.nlm.nih.gov/books/NBK459143/ 
  2. Smith, W.S., Johnston, S.C., Hemphill, J., Claude, I. I. I. (2018). Ischemic Stroke. In J.L. Jameson, et al. (Eds.), pp. 3079–3091, Harrison’s Principles of Internal Medicine, 20e. McGraw-Hill Education.
  3. Powers, W.J., et al. (2019). Guidelines for the Early Management of Patients With Acute Ischemic Stroke: 2019 Update to the 2018 Guidelines for the Early Management of Acute Ischemic Stroke: A Guideline for Healthcare Professionals From the American Heart Association/American Stroke Association. Stroke, 50(12), e344–e418. https://doi.org/10.1161/STR.0000000000000211 
  4. Kasner, S. (2021). Stroke and other cerebrovascular diseases. DeckerMed Medicine. Retrieved July 31, 2021, from doi:10.2310/.1027.
  5. Furie, K.L., Rost, N.S. (2021). Definition, etiology, and clinical manifestations of transient ischemic attack. UpToDate. Retrieved August 5, 2021, from https://www.uptodate.com/contents/definition-etiology-and-clinical-manifestations-of-transient-ischemic-attack
  6. Caplan, L.R. (2019). Differential diagnosis of transient ischemic attack and acute stroke. UpToDate. Retrieved August 6, 2021, from https://www.uptodate.com/contents/differential-diagnosis-of-transient-ischemic-attack-and-acute-stroke

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