Understanding Stroke: Types, Impact, and Statistics

• Stroke, or cerebrovascular accident (CVA), is an acute neurological deficit caused by disrupted blood flow to the brain
• Strokes are classified as ischemic (87% of cases, due to blockage) or hemorrhagic (13%, due to vessel rupture).
• Ischemic strokes result from thromboembolic events.
• Hemorrhagic strokes involve bleeding into brain tissue or subarachnoid spaces.
• Rapid recognition and treatment are critical to minimize brain damage.
• 2 million neurons die per minute during acute ischemia.
• Strokes are the 5th leading cause of death in the U.S. and a major cause of adult disability.
• Stroke is the second leading cause of death worldwide.
• 6.2 million deaths from stroke occurred in 2015, an increase of 830,000 since 2000.
• The lifetime global risk of stroke from age 25 onward in 2016 was 25%, an increase of 8.9% from 1990.
• Nearly 7 million Americans age 20 or older report having had a stroke.
• The prevalence is estimated to rise by 3.4 million adults in the next decade, representing 4% of the entire adult population.
• Stroke is likely to remain the second most common disabling condition in individuals aged 50 or older worldwide.
• A stroke is defined as an abrupt onset of a neurologic deficit attributable to a focal vascular cause.
• Diagnosis includes clinical assessment and laboratory studies, including brain imaging.
• Clinical manifestations of stroke are highly variable.
• Cerebral ischemia is caused by a reduction in blood flow that lasts longer than several seconds.
• Neurologic symptoms are manifest within seconds because neurons lack glycogen, so energy failure is rapid.
• Infarction or death of brain tissue results if the cessation of flow lasts for more than a few minutes.
• When blood flow is quickly restored, brain tissue can recover fully and the patient's symptoms are only transient; this is called a transient ischemic attack (TIA).
• Transient Ischemic Attack (TIA) definition requires that all neurologic signs and symptoms resolve within 24 hours without evidence of brain infarction on brain imaging.
• Stroke has occurred if the neurologic signs and symptoms last for >24 hours or brain infarction is demonstrated.
• A generalized reduction in cerebral blood flow due to systemic hypotension usually produces syncope.
• If low cerebral blood flow persists for a longer duration, then infarction in the border zones between the major cerebral artery distributions may develop.
• Global hypoxia-ischemia causes widespread brain injury; the constellation of cognitive sequelae that ensues is called hypoxic-ischemic encephalopathy.
• Focal ischemia or infarction is usually caused by thrombosis of the cerebral vessels themselves or by emboli from a proximal arterial source or the heart.
• Intracranial hemorrhage produces neurologic symptoms by producing a mass effect on neural structures, from the toxic effects of blood itself, or by increasing intracranial pressure.
• Transient Ischemic Attack (TIA) is a short-term interruption in blood flow to the brain that resolves within 24 hours with no residual brain damage.
• TIA is considered a major warning that an individual is a risk for a stroke.
• Stroke (Cerebrovascular Accident) is an interruption of blood circulation to the brain causing a neurologic deficit that reflects the area of the brain affected.
• Strokes can be ischemic (more common) or hemorrhagic (more deadly).
• Stroke is the 5th leading cause of death, an improvement from when it was the 3rd leading cause.
• Management has improved outcomes significantly.
• Racial disparity is considerable with AA males and females twice as likely to have a stroke and with higher mortality than other races.
• The estimated annual cost is $36.5 billion.
• 15% to 30% of survivors are permanently disabled, placing a large burden on long-term care facilities.

Etiology

• Ischemic strokes are caused by atherosclerosis, cardioembolism, or small-vessel disease (lacunar strokes).
• Hemorrhagic strokes are caused by hypertension, aneurysms, arteriovenous malformations, or anticoagulant use.

Subarachnoid Hemorrhage

• Bleeding occurs between the tissue that covers the brain and the brain.
• It is usually caused by aneurysm, AV malformation, or bleeding disorder.

Intracerebral Hemorrhage

• Bleeding occurs within the brain tissue itself.
• It is usually caused by a weakened artery in the brain with uncontrolled hypertension being the primary factor.
• In both cases the area surrounding the injury dies from the lack of oxygen and the failure of the ATP pathway.
• Intracellular calcium release contributes to cell death.

Risk Factors

• Modifiable risk factors Hypertension, diabetes, smoking, obesity.
• Non-modifiable risk factors Age (>55), male sex, Black race, and genetic predisposition.

Incidence

• 795,000 strokes per year occur in the U.S., with 610,000 being first-time events.
• Incidence doubles each decade after age 55.
• 34% of strokes occur in individuals <65.
• Women face higher lifetime stroke risk (1 in 5) due to factors like pregnancy and atrial fibrillation.
• 80% of strokes can be prevented.

Risk Factors

• Hypertension is the strongest modifiable risk factor.
• Atrial fibrillation increases stroke risk 5-fold.
• Diabetes doubles risk due to microvascular damage.
• Ischemic strokes tend to occur in older patients with co-morbidities.
• Other Risk Factors hypertension, older age, cigarette smoking, male gender, family history, race, previous stroke or TIA, carotid stenosis of more than 80%, atrial fibrillation, and drug abuse
• Other Risk Factors diabetes, obesity, sedentary lifestyle, and hyperlipidemia
• Hemorrhagic strokes tend to occur in healthy individuals between the ages of 40 and 60 years.
• Risk Factors include uncontrolled hypertension, (most common cause), smoking, hyperlipidemia, obesity, diabetes, heart disease, family history of stroke, use of blood thinners, arterio-venous malformations, trauma, aneurysms.

Prevention

• Primary prevention Mediterranean diet, exercise, smoking cessation, and BP control (<130/80 mmHg).
• Secondary prevention Statins, antiplatelets, and anticoagulants for AFib.
• Screening Annual BP checks, carotid ultrasound for high-risk patients.

Clinical Manifestations

• Sudden hemiparesis Unilateral weakness due to corticospinal tract involvement.
• Aphasia Broca's (expressive) or Wernicke’s (receptive) area damage.
• Vision loss Homonymous hemianopia from occipital lobe ischemia.
• Ataxia Cerebellar or brainstem involvement.
• Thunderclap headache Sudden, severe pain in subarachnoid hemorrhage.
• Review of Systems Neurological: Weakness, numbness, speech difficulties., Visual: Diplopia, blindness., Cardiac: Palpitations (AFib), chest pain. Gastrointestinal: Dysphagia, nausea., Psychiatric: Depression, emotional lability.

Physical Assessment Findings

• Facial asymmetry Drooping mouth/nasal labial fold (CN VII involvement).
• NIH Stroke Scale (NIHSS) Quantifies deficits, Sensory loss Unilateral neglect or hemisensory deficits., Dysarthria Slurred speech (cranial nerves IX/X)., Babinski sign Upper motor neuron lesion.

Assessment Tools & Grading

• NIHSS Scores 0-42; ≥6 indicates likely large-vessel occlusion.
• ABCD2 Score Predicts stroke risk post-TIA.

Clinical Algorithms

• FAST Assessment: Face drooping, Arm weakness, Speech difficulty → Time to call 911.
• Imaging First Non-contrast CT to rule out hemorrhage; MRI for ischemic penumbra.
• Reperfusion tPA within 4.5 hours or thrombectomy ≤24 hours for large-vessel occlusion.

Differential Diagnoses

• Migraine with Aura Gradual onset, scintillating scotoma Clinical history, Seizure Postictal confusion, rhythmic movements EEG, Hypoglycemia Confusion, blood glucose <70 mg/dL Glucose test, Bell's Palsy Forehead sparing, no limb weakness Clinical exam, Brain Tumor Progressive deficits, contrast-enhancing MRI MRI with gadolinium Neurologic:, Cardiac (Post-Cardiac Arrest Ischemia):, Metabolic:, Psychiatric:, Immunologic:

Diagnostic Studies & Possible Findings

• CT Head Hyperdense artery sign (ischemia) or hyperdense blood (hemorrhage).
• MRI Brain Diffusion-weighted imaging (DWI) shows acute ischemia within minutes.
• Carotid Ultrasound >70% stenosis indicates need for endarterectomy.
• EKG Atrial fibrillation or STEMI.
• Labs Elevated LDL (>100 mg/dL), HbA1c (>7%), or thrombocytopenia.

Treatment Prioritization

• Immediate emergency room referral is required for all patients with suspected cerebrovascular events.
• Initial management will vary depending on presentation
• Risk management is a primary factor for all patients ABCD score can be helpful
• Patients s/p TIA (confirmed) with no symptoms can be treated in the out patient setting Emphasis should be on management of the causal factor (i.e. carotid stenosis or A-fib)
• Time is of the essence in all suspected strokes
• Community coordination is critical with integrated EMS and hospital services
• ER management includes CT, ABC maintenance, airway management, neurology consult, and BP monitoring to ensure perfusion
• If antihypertensive are needed oral agents are preferred for slow reduction
• Thrombolytic Agents - only for ischemic stroke
• tPA was approved in 1996 for ischemic stroke patients if administered within 3 hours of onset of symptoms
• 2009 revisions increased the time frame to 4.5 hours except for those on anti-coagulants, DM, hx of stroke, > 80 year
• Surgical Intervention Carotid endarterectomy, Coil placed by interventional radiology into aneurysm, Ventriculostomy to reduce intracranial pressure
• Rapid evaluation is essential for use of acute treatments such as thrombolysis or thrombectomy. However, patients with acute stroke often do not seek medical assistance on their own because they may lose the appreciation that something is wrong (anosognosia) or lack the knowledge that acute treatment is beneficial; it is often a family member or a bystander who calls for help. Therefore, patients and their family members should be counseled to call emergency medical services immediately if they experience or witness the sudden onset of any of the following: loss of sensory and/or motor

Special Considerations

• Wake-Up Strokes MRI-guided thrombolysis may be feasible.
• Pregnancy Avoid tPA in third trimester; prioritize mechanical thrombectomy.

Geriatric Considerations

• Higher bleeding risk with anticoagulants; monitor renal/hepatic function.
• Screen for dysphagia to prevent aspiration pneumonia.

Nonpharmacological Interventions

• Rehab: Physical, occupational, and speech therapy.
• Lifestyle: DASH diet, smoking cessation, aerobic exercise 150 mins/week.

Pharmacological Management

• Acute Ischemic:, tPA 0.9 mg/kg IV (10% bolus + 90% infusion over 1 hour) within 4.5 hrs of event., Aspirin 325 mg PO/NG within 48 hours.
• Hemorrhagic Reverse anticoagulants (e.g., vitamin K for warfarin). Nimodipine 60 mg PO q4h for vasospasm prevention.

Consultation/Referral

• Neurology All acute strokes for reperfusion decisions.
• Neurosurgery Hemorrhagic strokes, hydrocephalus, or hemicraniectomy.
• Rehab Medicine Post-stroke recovery planning.

Initial Diagnosis Patient Guidance

• Educate on FAST recognition and immediate EMS activation.
• Discuss medication adherence (e.g., statins, antihypertensives).
• Provide resources for smoking cessation and cardiac rehab.
• Risk Stratification, High Risk ABCD2 ≥4, AFib, or large-artery atherosclerosis, Low Risk ABCD2 ≤3, no cardiac emboli source

Follow Up

• 7-10 days post-discharge: Assess medication tolerance and rehab progress.
• 3 months: Repeat carotid imaging/LDL; adjust secondary prevention.

Expected Course

• 30% recover fully, 40% have moderate disability, 10% require long-term care.

Possible Complications

• Dysphagia 50% of patients; increases aspiration risk.
• Depression 30% incidence; screen with PHQ-9.
• Post-stroke seizures 5-10%, especially with cortical involvement.

Key Pearls

• "Time is Brain" tPA within 4.5 hours reduces disability by 30%.
• Mimics Matter: 20% of "strokes" are mimics (seizure, migraine).
• NIHSS ≥6 Predicts large-vessel occlusion; prioritize thrombectomy.