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Ischemic stroke


Neurology department


GUIDELINESEpidemiology IntroductionPathophysiology Risk factors Etiology Signs and symptoms Complications Diagnosis Treatments Prevention Rehabilitation Prognosis References

1- Heart disease: 614,3482-Cancer: 591,6993-Chronic lower respiratory diseases: 147,1014-Accidents (unintentional injuries): 136,0535-Stroke (cerebrovascular diseases): 133,1036-Alzheimer's disease: 93,5417-Diabetes: 76,4888-Influenza and pneumonia: 55,2279-Nephritis, nephrotic syndrome, and nephrosis: 48,14610- Intentional self-harm (suicide): 42,773

Number of deaths for leading :causes of death

Stroke is the 5th leading cause of death in the US and is a major cause of disability. Annually, 15 million worldwide suffer a stroke-5 million die and 5 million are permanently disabled .WHO estimates a stroke occurs every 5 ~800,000people in the US have a stroke each year. One American dies from a stroke every4 minutes, on averagekilling nearly 130,000 Americans each year, thats 1 of every 20 deaths.About87%of all strokes areischemic stroke , when blood flow to the brain is blocked.Stroke costs the United States an estimated34 -40$ billioneach yearTotal cost of stroke has been estimated at $65.5 billion in 2008.


highest death rates from stroke are in the southeastern United States

Annual Economic Costs of Stroke (All Types) In The US

INTRODUCTIONStroke is a syndrome consisting of rapidly developing (usually seconds or minutes) symptoms and/or signs of loss of focal (or sometimes global) CNS function. The symptoms last more than 24 hours or lead to death.Although the brain makes up only 2% of our body weight, it uses 20% of the oxygen you breathe.

Classification of Stroke


A transient ischemic attack (TIA) is sometimes called a "mini-stroke." It is different from the major types of stroke because blood flow to the brain is blocked for only a short time.lasting less than 24 hours - usually no more than 5 minutescaused by embolic, thrombotic or hemodynamic vascular mechanisms. Some transient episodes last longer than 24 hours, yet patients recover completely reversible ischaemic neurological deficits.

Transient ischemic attack (TIA) :

Is characterized by the sudden loss of blood circulation to an area of the brain, resulting in a corresponding loss of neurologic function. Acute ischemic stroke is caused by thrombotic or embolic occlusion of a cerebral artery and is more common than hemorrhagic stroke.It can occurin the carotid artery of theneck as well as other arteries.

Ischemic stroke

In an embolic stroke, a blood clot or plaque fragment forms somewhere in the body (usually the heart) and travels to the brain. Once in the brain, the clot travels to a blood vessel small enough to block its passage. The clot lodges there, blocking the blood vessel and causing a stroke. About 15% of embolic strokes occur in people with atrial fibrillation (Afib). The medical word for this type of blood clot is embolus.

:1- Embolic stroke

A thrombotic stroke is caused by a blood clot that forms inside one of the arteries supplying blood to the brain. This type of stroke is usually seen in people with high cholesterol levels and atherosclerosis. Two types of blood clots can cause thrombotic stroke: large vessel thrombosis and small vessel disease. Large Vessel Thrombosis The most common form of thrombotic stroke (large vessel thrombosis) occurs in the brains larger arteries. In most cases it is caused by long-term atherosclerosis in combination with rapid blood clot formation. High cholesterol is a common risk factor for this type of stroke.Small Vessel Disease Another form of thrombotic stroke happens when blood flow is blocked to a very small arterial vessel (small vessel disease or lacunar infarction). Little is known about the causes of this type of stroke, but it is closely linked to high blood pressure.

2- Thrombotic stroke

PATHOPHYSIOLOGYWhen an artery is acutely occluded by thrombus or embolus, the area of the CNS supplied by it will undergo infarction if there is no adequate collateral blood supply. Surrounding a central necrotic zone, an ischemic penumbra remains viable for a time, i.e. it may recover function if blood flow is restored.CNS ischemia may be accompanied by swelling for two reasons: cytotoxic oedema accumulation of water in damaged glial cells and neurones, vasogenic oedema extracellular fluid accumulation as a result of breakdown of the bloodbrain barrier.In the brain, this swelling may be sufficient to produce clinical deterioration in the days following a major stroke, as a result of a rise in intracranial pressure and compression of adjacent structures.


Atherosclerosis: decades-long process; progression favored by hypercholesterolemia, HTN, cigarette smoking

Fatty streak: yellowish discoloration on intimal surface of blood

Focal plaques: eccentric thickening at bifurcations; addition of massive extracellular lipids that displaced normal cells and matrix

Complicated fibrous plaques: central a cellular area of lipid covered by a cap of smooth muscle cells and collagen

Atherosclerosis and Thrombus Formation:Arterial Wall Injury

Functional alteration of endothelial cell layer

Denuding of endotheliumSuperficial intimal injury

Deep intimal & media damage with marked platelet aggregation and mural thrombosis


Cardiogenic EmboliCardiogenic emboli lodge in the middle cerebral artery or its branches in 80% of cases, in the posterior cerebral artery or its branches 10% of the time, and in the vertebral artery or its branches in the remaining 10% of cases.


less well documented Can be changed, treatable, controlled : Cannot Be Changed: Geographic location- southeastern US > other areas. so-called "stroke belt" states.Socioeconomic factors- some evidence strokes among low-income people > people with high-income .Alcohol abuse.Drug abuse.Acute infection*

High blood pressure.Cigarette smoking.Diabetes mellitusMany people with DM have high BP, dyslipidemia and overweight.Carotid or other artery disease.Peripheral artery disease.Atrial fibrillation~ 15% of embolic strokes occur in people with Afib.Other heart disease- CAD or HF etcTransient ischemic attacks (TIA).Sickle cell disease.High blood cholesterol.Poor diet.Physical inactivity and obesityIncreased age .Being male .Race (e.g., African-Americans) .Diabetes mellitus .Prior stroke/transient. ischemic attacks .Family history of strokeAsymptomatic carotid bruit.Genetic disorders .


UNCOMMON CAUSESCOMMON CAUSESHypercoagulable disordersProtein C deficiencyProtein S deficiencyAntithrombin III deficiencyAntiphospholipid syndromeFactor V Leiden mutation aProthrombin G20210Mutation aSystemic malignancySickle cell anemia-ThalassemiaPolycythemia veraSystemic lupus erythematosusHomocysteinemiaThrombotic thrombocytopenicpurpuraDisseminated intravascularcoagulationDysproteinemiasNephrotic syndromeInflammatory bowel diseaseOral contraceptivesVenous sinus thrombosis bFibromuscular dysplasiaVasculitisThrombosis: Lacunar stroke (small vessel) Large vessel thrombosis DehydrationEmbolic occlusion : Artery-to-artery Carotid bifurcation Aortic arch Arterial dissection Cardioembolic Atrial fibrillation Mural thrombus Myocardial infarction Dilated cardiomyopathy Valvular lesions Mitral stenosis Mechanical valve Bacterial endocarditis Paradoxical embolus Atrial septal defect Patent foramen ovale Atrial septal aneurysm Spontaneous echo contrast



Contralateral paresis and sensory loss in the leg.Cognitive or personality changes.

SIGNS & SYMPTOMS The symptoms last more than 24 hours or lead to death.Symptoms and signs of arterial infarcts depend on the vascular territory affected .


Pneumonic: CHANGesContralateral paresis and sensory loss in the face and the arm.Homonymous Hemianopsia.Aphasia.Neglect.Gaze preference toward the side of the lesion.


Pneumonic: The 4 Ds






Pure motor or sensory stroke.

Dysarthria-clumsy hand syndrome, ataxic hemiparesis.


ComaLocked-In SyndromeCranial Nerve PalsiesApneaVisual SymptomsDrop AttacksDysphagiaDysarthriaVertigoCrossed weakness and sensory loss affecting the ipsilateral face and contralateral body.

COMPLICATIONS Brain edema. Pneumonia- occurs as a result of not being able to move as a result of the stroke. Urinary tract infection (UTI) - can occur as a result of having a foley catheter .Seizures - common in larger strokes. Clinical depression - very common after stroke or may be worsened in someone who had depression before the stroke. Bedsores .Limb contractures .Deep venous thrombosis (DVT). myocardial infarction, arrhythmias and heart failure.fluid imbalance.spasticity, with pain, contractures and frozen shoulder,

Vital signsHeart rate .Blood pressure.Breathing.Temperature.BMI.O2 saturationPatient history

DIAGNOSISPhysical examinationAbsent pulses (inferior extremity, radial, or carotid) - favors atherosclerosis with thrombosisSudden onset of cold, blue limb- fav