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