Transcript Evaluating the Event - Heart and Stroke Foundation of Ontario

Preventing Strokes
One at a Time
Evaluating the
Event
2009
Acknowledgements
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The Heart and Stroke Foundation and Canadian Stroke
Strategy gratefully acknowledges the collaborative
contributions of healthcare professionals and stroke
programs across the country in the development of
this tool kit.
This resource and its components are based upon the
Canadian Best Practice Recommendations for Stroke
Care, updated 2008, and was developed to support
the implementation of the recommendations for stroke
prevention.
Canadian Stroke Strategy

Resources available at: www.heartandstroke.ca/profed
 Acute Stroke Management Resource
 Toolkit for the Canadian Best Practice
Recommendations for Stroke Care, updated 2008
 Pocket Reference Cards
 Faaast FAQ’s for Nurses
 National Professional Education Atlas
 NEW!! Stroke Prevention Tool Kit
Canadian Best Practice Recommendations for
Stroke Care, updated 2008: Prevention Sections

2.0 Prevention of
Stroke
2.1 Lifestyle and risk
factor management
2.2 Blood pressure
management
2.3 Lipid management
2.4 Diabetes
management
2.5 Antiplatelet therapy
2.6 Antithrombotic
therapy for atrial
fibrillation
2.7 Carotid intervention
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3.0 Hyperacute
Stroke
Management
3.2 Acute management of
transient ischemic
attack and minor
stroke
CMAJ 2008;179(12 Suppl):E1-E93
Preventing Strokes One at a Time
Workshop Learning Objectives
Upon completion, participants will be able to:
 Discuss the incidence of TIA/minor stroke and
the risk of recurrent stroke
 Describe four steps of secondary stroke
prevention
 Implement Canadian Best Practice
Recommendations for Stroke Care in the
evaluation and identification of risk with TIA
and minor stroke patients
 Identify patients at high risk of recurrent
stroke
Outline
Overview of Stroke & TIA
 Etiology
 Stroke Risk
 Diagnostic investigations

Impact of Stroke in Canada
~ 50,000
strokes/year
Someone has a
stroke
every 10 minutes
20% chance of
second stroke
within 2 years
For every symptomatic
stroke there are 9 ‘silent’
strokes resulting in
cognitive impairment
300,000 Canadians
living with stroke
16,000 Canadians
die from stroke
each year
Price Tag:
$3.6 billion annually
Stroke
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Sudden onset
Focal neurological
symptoms
Interruption in blood
supply to a part of the
brain
WHO >24 hours
Typical > 1 hour
Permanent damage
TIA
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Sudden onset
Focal neurological
symptoms
Transient lack of
blood supply and focal
ischemia
WHO < 24 hours
Typical < 1 hour
No permanent
damage to the brain
Warning Signs: Stroke/TIA
Sudden loss of strength or sudden numbness in
the face, arm or leg, even if temporary
Sudden difficulty speaking or understanding or
sudden confusion, even if temporary
Sudden trouble with vision, even if temporary
Sudden severe and unusual headache
Sudden loss of balance especially with any of the
above signs
CALL 911
HSFC, 2006
Evaluate the Event: Investigating and
Stratifying Risk
Canadian Best Practice Recommendations for Stroke Care, 2008
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3.2 Acute management of TIA and Minor Stroke
 “Patients who present with symptoms suggestive
of minor stroke or TIA must undergo a
comprehensive evaluation to confirm the
diagnosis and begin treatment to reduce the risk
of major stroke as soon as is appropriate to the
clinical situation.”
.
CMAJ 2008;179(12 Suppl):E1-E93 #3.2
ETIOLOGY
“The approach to secondary stroke
prevention is dependent upon the
underlying cause, or mechanism of the
initial event and the existing stroke risk
factors.” (APSS, Feb 2009)
Ischemic (80%)
Hemorrhagic (20%)
Ischemic Stroke: Etiology
 Large
Vessel Disease
 Atherosclerosis
 Small
Vessel Disease
 Lacunar Infarction
 Cardioembolic
 Cryptogenic
Stroke Mimics
Patients can present with deficits that initially
can resemble stroke making TIA difficult to
diagnose
 History, assessment, and imaging all
contribute to the assessment and identification
of stroke mimics
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Stroke Prevention
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Primary:
 an individually based clinical approach to disease prevention
 directed toward preventing the initial occurrence of a disorder
in otherwise healthy individuals
 Recommendations related to stroke emphasize the importance
of screening and monitoring those patient at high risk of a first
stroke
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Secondary:
 An individually based clinical approach to reducing the risk of
recurrent vascular events in individuals who have already
experienced a stroke or TIA and in those who have one or
more of the medical conditions or risk factors that place them
at high “risk of stroke”
 Recommendations are directed to those risk factors most
relevant to stroke
CMAJ 2008;179(12 Suppl):E1-E93, p. E16
The Road to Prevention
Are all TIA/minor stroke patients at risk of
subsequent stroke?
Is early identification of those at highest risk
of stroke critical?
STROKE RISK
Risk of Recurrent Stroke
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People with symptoms of a TIA are at higher risk
for subsequent stroke
 11.5 % will have a stroke within 90 days
 Of these patients 50% will have a stroke within
48 hours
Johnston et al (2000) & Gladstone et al (2004)
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20%-40% of strokes are preceded by a TIA or
non disabling stroke
(Rothwell et al. Lancet Neurol 2006; 5: 323-331)
Risk Factors
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Modifiable
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Hypertension
Obesity
Atrial Fibrillation
Diabetes
Cardiac Disease
Dyslipidemia
Excessive Alcohol Intake
Physical Inactivity
Smoking
Stress
Diet
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Non-Modifiable
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Age
Gender
Family History
Ethnicity
Previous TIA or
Stroke
An Approach to Secondary Stroke
Prevention
Four Step Process
 Evaluate the Event
 Initiate Medications
 Implement Interventions
 Modify Stroke Risk Factors
Adapted from APSS, February 2009
Step 1: Evaluate the Event
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TIA/Minor Stroke Risk Assessment
 Clinical Predictors
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Investigations
 CT or MRI, ECG, Carotid Imaging, Blood work
Evaluate the Event: Investigating and
Stratifying Risk
Canadian Best Practice Recommendations for Stroke Care, 2008
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3.2a.i “All patients with suspected TIA or Minor
Stroke should have an immediate clinical
evaluation and additional investigations as
required to establish the diagnosis, rule out stroke
mimics and develop a plan of care
3.2a.ii “Use of a standardized risk stratification
tool at the initial point of health care contactwhether first seen in primary, secondary or
tertiary care-should be used to guide the triage
process.”
.
CMAJ 2008;179(12 Suppl):E1-E93 #3.2
Evaluate the Event: Risk Stratification
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Emergent
 Symptoms within previous 24 hours with 2 or more high
risk clinical features
 Acute/persistent or fluctuating stroke symptoms
 1 positive investigation
 Other factors based on individual presentation and
clinical judgement
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Urgent
 TIA within 72 hours
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Semiurgent
 Does not fit in urgent or emergent
CMAJ 2008;179(12 Suppl):E1-E93, #3.2
Evaluate the Event: Investigating and
Stratifying Risk
Canadian Best Practice Recommendations for Stroke Care, 2008
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3.2a.iii “Patients with suspected TIA or
minor stroke should be referred to a
designated stroke prevention clinic or to a
physician with expertise in stroke
assessment and management, or if these
options are not available, to an emergency
department that has access to
neurovascular imaging facilities and stroke
expertise.”
.
CMAJ 2008;179(12 Suppl):E1-E93 #3.2
Evaluate the Event: Timing of Tests
Diagnostic Test
Emergent
Urgent
Semiurgent
Assessment by
medical specialist
trained in stroke
24 h
7d
30 d
CT or MRI
24 h
7d
30 d
Carotid Imaging
24 h
7d
30 d
ECG
24 h
7d
30 d
CMAJ 2008;179(12 Suppl):E1-E93 #3.2
Evaluate the Event: Example of a Risk
Stratification Tool
ABCD2 Score * not endorsed by the Canadian Stroke Strategy
Age
1 point for age >60
/1
BP
1 point for BP> 140/90
/1
Clinical
Features
2 points for focal weakness
1 point for speech disturbance without
weakness
/2
Duration
2 points for duration >60 minutes
1 point for duration >10min<59 minutes
/2
Diabetes
1 point for presence of diabetes
/1
Total score
Johnston, Rothwell et al. Lancet; 2007; 368: 283-292
/7
Evaluate the Event: Investigations
Labs
 CBC,
 Electrolytes, Urea,
Creatinine, LFT’s, CK
 INR
 Fasting Glucose
 Hb A 1C
 Fasting Lipid Profile
o Total Cholesterol
o HDL
o LDL
o Triglycerides
Diagnostics
 CT head, MRI
 Carotid Imaging
(Carotid Doppler, CTA,
MRA)
 CXR
 ECG
 Echocardiogram
 Holter Monitor
Evaluate the Event: Investigations
Neurovascular Imaging
Test
Rationale
Outcome
CT or
MRI
Rule out mimics,
Identify stroke type
MRI: Better
visualization of acute
stroke
Diagnosis; begin appropriate
interventions. All TIA minor
stroke patients should receive a
CT scan of the head ASAP.
Carotid
Identify carotid
Imaging stenosis. Prompt
(Carotid
carotid imaging is
Doppler,
essential
CTA, MRA)
Goal to TX within 2 weeks (7099% stenosis:90 day risk of
stroke is 25%)
Evaluate the Event: Investigations
Test
Rationale
Outcome
Other Labs:
CK, LFTs,
INR, PTT,
Fasting
lipids &
glucose,
HbA1C
CK, LFT: Baseline values
prior to statin ; INR: risk of
hemorrhage & assessment
of Coumadin efficacy:
Glucose: Identify & treat
early diabetes, HbA1C (if
diabetic)
Statins can ↓ further
vascular events by 25%;
Sub-therapeutic INR (<2)
puts patients at High risk
for further event
ECG
Screen for Atrial Fibrillation.
Treat with Coumadin.
ECHO/ TEE
If suspicion of cardiac
source. TEE Assists to
identify PFO, shunts
Expedites proper
treatment &management.
Holter
Monitor
If you suspect atrial
fibrillation
Expedites proper
treatment & management
An Approach to Secondary Stroke
Prevention
Four Step Process

Evaluate the Event √
Initiate Medications
 Implement Interventions
 Modify Stroke Risk Factors

APSS, February 2009
Canadian Best Practice Recommendations for Stroke Care, updated 2008
www.canadianstrokestrategy.ca