Types of Stroke

Types of Stroke

  • Strokes are classified based on underlying pathophysiologic findings
    • Ischemic
      • Thrombotic
        • Men more than women
        • The process of clot formation (thrombosis) results in a narrowing of the lumen, which blocks the passage of the blood through the artery.
        • Most common cause of stroke (60%)
          • Often associated with HTN and DM
          • Many times they are preceded by TIA
        • Extent of stroke depends on
          • Rapidity of onset
          • Size of damaged area
          • Presence of collateral circulation
      • Embolic
        • Men more than women
        • An embolus is a blood clot or other debris circulating in the blood. When it reaches an artery in the brain that is too narrow to pass through, it lodges there and blocks the flow of blood.
        • Results in infarction and edema of area supplied by involved vessel
        • 2nd most common cause of stroke
        • Sudden onset with severe clinical manifestations
          • Warning signs are less common
          • Patient usually remains conscious
          • Prognosis is related to amount of brain tissue deprived of blood supply
          • Commonly recur
    • Hemorrhagic
        • A burst blood vessel may allow blood to seep into and damage brain tissues until clotting shuts off the leak.
      • Intracerebral/intraparenchymal hemorrhage
        • Slightly higher in women
        • Bleeding within brain caused by rupture of a vessel
          • Sudden onset of symptoms
          • Progression over minutes to hours because of ongoing bleeding
          • Prognosis is poor with a 30-day mortality rate of 40%-80%
        • Manifestations
          • Neurologic deficits
          • Headache
          • Nausea and/or vomiting
          • Decreased levels of consciousness
          • Hypertension
      • Subarachnoid/ intraventricular hemorrhage
        • Slightly higher in women
        • Intracranial bleeding into cerebrospinal fluid–filled space between arachnoid and pia mater
        • Commonly caused by rupture of a cerebral aneurysm, trauma, or drug abuse
      • Cerebral aneurysm
        • Majority are in Circle of Willis
        • Incidence ↑ with age; higher in women
        • Silent killer
          • Loss of consciousness may or may not occur
          • High mortality rate
          • Survivors often suffer significant complications and deficits