Download Stroke PCAP 2005

Stroke:
An Introduction
Maarten Lansberg, MD, PhD
Neil Schwartz, MD, PhD
Stanford Stroke Center
Outline
• Background
• Stroke Diagnosis
• Stroke Treatment
• Stroke Prevention
What is a Stroke?
(Brain Attack)
Disruption of blood flow to
part of the brain caused by:
• Occlusion of a blood vessel
(ischemic stroke)
OR
• Rupture of a blood vessel
(hemorrhagic stroke)
Types of Stroke
84%
Total Ischemic
53%
Thrombotic
31%
Embolic
Intracerebral
Subarachnoid
0%
Ischemic
Hemorrhagic
10%
6%
20%
40%
60%
Mohr JP, Caplan LR, Melski JW, et al. Neurology 1978;28:754-62
80%
100%
Anatomy
MR Angiogram
What happens with cutoff
of blood supply?
Oxygen deprivation to nerve cells in
the affected area of the brain -->
Nerve cells injured and die -->
The part of the body controlled by
those nerve cells cannot function.
What Causes Ischemic
Stroke?
Thrombotic
Embolic
Thrombus
Embolus
Ischemic Stroke
What happens with rupture of
a blood vessel?
Oxygen deprivation to nerve cells in
the affected area of the brain and
local destruction of nerve cells-->
Nerve cells injured and die -->
The part of the body controlled by
those nerve cells cannot function.
Intracerebral Hemorrhage
Head CT:
Ischemic or Hemorrhagic Stroke?
Head CT:
Ischemic or Hemorrhagic Stroke?
Stroke Impact
• 750,000 strokes per year
• Third leading cause of death
(1st: heart disease, 2nd: all cancers)
– Over 160,000 deaths per year
• Over 4 million stroke survivors
1. Williams GR, Jiang JG, Matchar DB, et al. Stroke 1999; 30:2523-28.
2. Hoyert DL, Kochanek KD, Murphy SL. National Vital Statistics Report 1999; 47:19.
Stroke Impact (2)
• Leading cause of adult disability
– Of those who survive, 90% have
deficit
• Half of all patients hospitalized for
acute neurological disease.
• Stroke costs the U.S. $30 to $40
billion per year.
The Stroke
Belt
Perry HM, Roccella EJ. Hypertension
1998;6:1206-15.
2. Stroke Diagnosis
Symptoms of Stroke
• Sudden numbness or weakness of face,
arm or leg, especially on one side of the
body
• Sudden confusion, trouble speaking or
understanding
• Sudden trouble seeing from one or both
eyes
• Sudden unsteadiness, dizziness, loss of
balance or coordination
• Sudden severe headache with no
known cause
Other Stroke Symptoms
• Also common following stroke
– Depression
– Other emotional problems
– Memory problems
Common Stroke Patterns
• Left (Dominant) Hemisphere:
– Aphasia
– Right hemiparesis
– Right hemisensory loss
– Right visual field defect
– Left gaze preference
– Dysarthria
– Difficulty reading, writing, or calculating
Common Stroke Patterns (2)
• Right (Nondominant) Hemisphere:
– Left hemiparesis
– Left hemisensory loss
– Left neglect
– Left visual field defect
– Right gaze preference
– Dysarthria
Common Stroke Patterns (3)
• Brainstem/Cerebellum/Posterior Circulation
– Motor or sensory loss in all 4 limbs
– Crossed signs (face vs. body)
– Limb or gait ataxia
– Dysarthria
– Dysconjugate gaze
– Nystagmus
– Amnesia
– Cortical blindness
Common Stroke Patterns (4)
• Small Vessel (Lacunar) Strokes
(Subcortical or Brain Stem)
– Pure Motor
• Weakness of face, arm, leg
– Pure Sensory
• Decreased sensation of face, arm, leg
Differential Diagnosis
• Stroke (ischemic; hemorrhagic)
• Intracranial mass
– Tumor
– Subdural hematoma
• Seizure with persistent neurological signs
• Migraine with persistent neurological signs
• Metabolic
– Hyper/Hypoglycemia
• Infectious
– Meningitis / Encephalitis / Cerebral
abscess
– Systemic
3. Stroke Treatment
Time
is
Brain
EMS/ED evaluation
of acute stroke
• Assure adequate airway
• Monitor vital signs
• Conduct general assessment
– Evidence of trauma to head or neck
– Cardiovascular abnormalities
EMS/ED evaluation
of acute stroke (cont.)
• Conduct neurological examination
– Level of consciousness (Glasgow Coma Scale)
– Presence of seizure activity
– NIH Stroke Scale
ED evaluation of acute stroke:
diagnostic tests
•
•
•
•
•
Non-contrast Head CT
EKG
Blood Glucose
CBC, platelets, PTT, PT/INR
Serum electrolytes
t-PA therapy
tPA therapy for acute stroke
• Candidate for IV tPA?
– Stroke onset < 3 hours (When was the
patient last seen at baseline ?)
• Benefit: 12 % increased chance of good
recovery
• Risk: bleeding (up to 6%)
tPA exclusion criteria
–
–
–
–
–
–
–
–
–
–
–
–
–
–
–
–
Symptoms mild or rapidly resolving
SBP > 180 or DBP > 110
Blood on head CT
History of ICH
CNS tumor or vascular malformation
Bacterial endocarditis
Known bleeding disorder
PTT > 40; PT > 15 (INR > 1.7)
Stroke within 3 months
Significant trauma in last 3 months
GI/GU/Resp hemorrhage within 21 days
Major surgery within 14 days / minor
surgery within 10 days
Peritoneal dialysis or hemodialysis
Seizure at onset of stroke
Glucose <50 or >400
Pregnant
Other therapies for acute stroke
• IV t-Pa outside the three hour
window
• IA t-PA
• IA mechanical
thrombolysis/thrombectomy
• Neuroprotective agents
Stroke Management
If not a candidate for acute intervention, then focus
on:
– Prevention of recurrent stroke
• Diagnostic evaluation for stroke etiology
• Risk factor assessment
– Rehabilitation (PT/OT/SLP)
– Prevention of Complications
• DVT, aspiration PNA, decubitus ulcers, falls
Diagnostic stroke evaluation
• Purpose: Identify location, size, and cause of
stroke
• Tests may include:
–
–
–
–
–
–
–
–
Follow-up head CT
Brain MRI/MRA
Carotid ultrasound
Cardiac echo (transthoracic or transesophageal)
Cerebral angiogram or CT angiogram
Lipid panel
Hemoglobin A1c
Hypercoagulable tests: antiphospholipid antibodies,
Protein C & S, Antithrombin III, Factor V Leiden
mutation, Prothrombin 20210A mutation…
4. Stroke Prevention
Percent of patients with events
Stroke survivor’s greatest risk is
another stroke
16
14
Stroke
14%
Heart Attack
13%
13%
12
10%
10
8
7%
6
4
3%
3%
2%
2
CATS
TASS
CAPRIE*
ESPS 2
* Stroke patient subgroup only (n = 6,431)
Albers, G.W. Neurology. 2000;14;54(5):1022-8.
Transient Ischemic Attack (TIA)
• Stroke symptoms resolve in less than 24
hours (most resolve in < 1 hour)
• Warning sign for stroke and heart attack
– One third go on to have a stroke within 5 years
• Stroke risk can be reduced
• Opportunity to prevent full stroke
Stroke risk factors
Non - Modifiable
• Age
• Gender (men)
• Heredity: family history of stroke, hypercoagulable
states
• Race/ethnicity (e.g. African Americans)
Sacco RL, Benjamin EJ, Broderick JP, et al. Stroke: 1997;28:1507-17.
Stroke risk factors
Modifiable
Behaviors
 Cigarette smoking
 Alcohol abuse
 Physical inactivity
Sacco RL. et al. Stroke. 1997;28:1507-1517
1998;279:1288-1292
Medical Conditions
• Hypertension
• Heart disease
• Atrial fibrillation
• High Cholesterol
• Diabetes
• Carotid stenosis
• Prior stroke or TIA
Pancioli AM et al. JAMA.
How many strokes can be prevented?*
360,000
HTN
146,000
Cholesterol
90,000
Smoking
69,000
AF
34,000
Heavy Alcohol
Use
0
100,000
200,000
Adapted from Gorelick PB. Arch Neurol 1995;52:347-55
*Based on an estimated 731,000 strokes annually
300,000
400,000
Hypertension
JNC VII Guidelines
Events
Cardiovascular
Cardiovascular Events (%)
Lower blood pressure =
Lower Risk
<<140/90
140/90
< 130/85
< 130/85
< 120/80
< 120/80
Vasan RS et al N Engl J Med 345; 1291-7, 2001
PROGRESS Trial
Blood pressure reduction following stroke
Stroke Rate (%)
20
28% relative risk
reduction
15
10
14%
10%
Placebo
Active
5
0
1
2
3
Follow-up time (years)
Progress, Lancet. 2001;358:1033-41
4
Risk factor modifications
for blood lipids
National Cholesterol Education Program
(NCEP) Guidelines
Condition
Hyperlipidemia or
atherosclerotic
disease
(LDL >100 mg/dL)
Recommendation
• Diet: decrease fat and
cholesterol
• Exercise
• Add pharmacologic
therapy: statin agents
Expert Panel on Detection, Evaluation, and Treatment of High Blood Cholesterol in Adults. JAMA 1993;269:3015-23.
Risk factor modifications for DM
ADA Recommendations to Reduce Microvascular
Complications
• Average pre-prandial glucose <120 mg/dL
• Average bedtime glucose 100 to 140 mg/dL
• HbA1c <7%
1. Lukovitis TG, Mazzone T, Gorelick PB. Neuroepidemiology 1999;18:1-14.
2. Diabetes Care 1998;21 (Suppl 1):1-200
Lifestyle Risk Factor Modifications
Lifestyle Factor
• Cigarette Smoking
Recommendation
• Counseling
• Nicotine replacement therapy
• Bupropion
• Alcohol use
• Up to 2 drinks/day for men, 1 drink/day
for women, or lighter individuals
• Physical activity
• Brisk activity (30 to 60 min/day)
• Diet
• 5 servings/day fruit and vegetables
• Limit saturated fat (<30% total energy)
Gorelick PB, Sacco RL, Smith DB, eet al.
JAMA 1999;281:1112-1120.
Prevention of Blood Clot Formation
Müller, 1997
Medications that prevent stroke
“Blood thinners”
Anticoagulants
Antiplatelet Agents
•Coumadin (warfarin)
•Aspirin
•Exanta
•Aspirin/extended release
dipyridamole (Aggrenox)
•Heparins
•Clopidogril (Plavix)
•Ticlopidine (Ticlid)
Aspirin for prevention of stroke
•Aspirin benefit independent of dose and
gender
•FDA, AHA & ACCP all recommend
– an aspirin dose between 50 and 325 mg/day
Albers GW at al Neurology 1999;53(suppl. 4):S25-S38
FDA. Federal Register. 1998;63:56802.
Albers GW, et al. Chest 2001, 119: 300S-320S.
Choice of medication for stroke
prevention
What is the cause of the stroke?
Atherosclerosis
Unknown
Antiplatelet therapy
Heart
Warfarin
(Coumadin)
Albers GW, et al. Chest 1998;114:683S-698S
Barnett HJ et al. N Engl J Med. 1998;339:1415-1425
Prevention of recurrent stroke
Stroke caused by atrial fibrillation
Relative Risk Reduction
80%
66%
60%
Benefit of aspirin
Benefit of warfarin
40%
20%
15%
0%
EAFT Study Group Lancet 1993, 342: 1255-62
How to prevent a stroke
• Control treatable risk factors
• Take an anti-platelet agent
or an anti-coagulant
• Surgical therapy for carotid
stenosis
Changing the perception of stroke
MYTH
• Stroke is unpreventable
• Cannot be treated
• Strikes only the elderly
• Recovery ends 6
months after a stroke
REALITY
• Stroke is largely
preventable
• Requires urgent
treatment
• Can happen to anyone
• Stroke recovery can
continue throughout life
Stroke Websites
American Stroke Association:
www.strokeassociation.org
National Stroke Association:
www.stroke.org
Stanford Stroke Center
www.stanford.edu/group/neurology/stroke/