STUDY NOTES — STROKE (CEREBROVASCULAR ACCIDENT / CVA)

I. Overview

• Definition: Sudden loss of neurologic function due to disruption of cerebral blood flow.

• Epidemiology:

  • #3 cause of death in the U.S.

  • #1 cause of neurologic disability in the U.S.

• Major Categories of Stroke:

  1. Ischemic Stroke (≈ 85%)

     • Due to blocked blood vessel

     • Subtypes: Thrombotic and Embolic

  2. Hemorrhagic Stroke (≈ 15%)

     • Due to ruptured blood vessel

     • Types: Intracerebral hemorrhage (ICH) or Subarachnoid hemorrhage (SAH)

II. Pathophysiology

A. Ischemic Stroke

1. Thrombotic

   • Caused by atherosclerotic plaque → clot forms at vessel site

   • Similar mechanism as MI, but in the brain

2. Embolic

   • Clot forms elsewhere → travels to cerebral artery

   • Common sources:

     • Atrial fibrillation

     • Mechanical/prosthetic valves

     • Carotid plaque

     • DVT crossing through PFO → paradoxical embolus

B. Hemorrhagic Stroke

• Rupture of an artery → bleeding into brain tissue or subarachnoid space

• Worst prognosis, 30–50% 30-day mortality

• Risk factors:

  • Hypertension (most common)

  • Berry aneurysm rupture (SAH)

  • Trauma

  • Anticoagulants

III. Risk Factors (Ischemic & Hemorrhagic)

Category	Risk Factors
Atherosclerosis-related	HTN, Diabetes, Hyperlipidemia, Smoking, Age, Obesity
Cardioembolic	A-fib, Valvular disease
Young Pt Causes	OCP use, Protein C/S deficiency, Sickle cell, PV, Cocaine/meth, Arteritis, Hypercoagulable states
Hemorrhage-specific	HTN, Aneurysm, Trauma, Anticoagulants

IV. Clinical Presentation

A. Subarachnoid Hemorrhage (SAH)

• “Thunderclap headache” — worst headache of life

• Rapid onset + neck stiffness, vomiting

• Xanthochromia on LP

• Commonly at Circle of Willis branch points

B. Artery-Specific Stroke Symptoms

Artery	Key Symptoms
ACA	Leg & foot paralysis; confusion (frontal lobe)
MCA	Face + arm paralysis; aphasia (dominant hemisphere)
PCA	Vision loss (occipital lobe)
Basilar / Pontine	Locked-in syndrome
Cerebellar arteries	Ataxia, dysdiadochokinesia, coordination loss
Vertebral/Basilar	Syncope

V. Initial Workup & Acute Management (First 24–48 hrs)

1. Immediate Test:
   CT head WITHOUT contrast

   • If blood present → Hemorrhagic stroke

   • If no blood → Ischemic stroke

If HEMORRHAGIC

• Consult neurosurgery (coiling > clipping)

• Lower BP to SBP <150

• Give FFP if coagulopathy

• Manage ICP: LPs, shunt, or craniotomy

• Calcium channel blockers (e.g., Nimodipine) → prevent vasospasm (especially SAH)

• Seizure prophylaxis

If ISCHEMIC

• Consider tPA if eligible:

  • Time window: ≤ 3–4.5 hours from known symptom onset

  • Do NOT give tPA if:

    • Prior brain bleed

    • Recent head trauma or surgery (<21 days)

    • Unknown stroke onset time

• Permissive hypertension allowed (up to SBP 200–220) unless tPA given

• Additional workup:

  • EKG (look for Afib)

  • Echocardiogram (cardioembolic source)

  • Carotid ultrasound → If >70–80% stenosis, consider endarterectomy or stent

VI. Chronic Long-Term Management (Prevention)

Patients need lifelong secondary prevention:

Goal	Management
BP < 140/80	ACEIs, diuretics, etc.
LDL control	High-intensity statin (Atorvastatin 40–80 or Rosuvastatin 20–40)
A1c < 7%	Metformin ± others
No smoking	Mandatory
Antiplatelet	Aspirin for life (or Clopidogrel)
Anticoagulation	For Afib or embolic source (NOACs or Warfarin)

• CHADS₂ / CHA₂DS₂-VASc: stroke = 2 points → automatic lifelong anticoagulation

VII. Key Board Exam Pearls

• CT without contrast FIRST always

• tPA window = 3–4.5 hrs

• SAH = thunderclap + xanthochromia

• MCA = face/arm + speech

• Permissive HTN ONLY in ischemic without tPA

• Statin for all stroke patients