Cardiac Stress Testing
What is a stress test?
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A progressive graded test that reproduces
diagnostic, prognostic, and functional abnormalities
in clients with cardiovascular and pulmonary
disorders
Evaluates electrocardiographic, hemodynamic, and
symptomatic responses to exercise in a controlled
environment
Assesses exercise tolerance and can produce
symptoms not present at rest
Indications for Cardiac Stress Testing
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Diagnosis
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Indicated for those with symptoms of CAD
Indicated for those with multiple risk factors
Used in context with other clinical data
Prognosis
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Evaluation of those with known or suspected CAD
Predict long-term mortality based on ECG findings
at rest, during exercise and in exercise recovery
Indications for Stress Testing
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Post myocardial infarction
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May be done as early as four days post MI
Prognostic assessment
Activity prescription
Functional capacity
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Exercise prescription
Activity counselling
Return to work
Standardized Stress Testing Protocols
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Astrand
Bruce – Protocol used with treadmill stress
testing at TBRHSC
Balke
Ellestad
Naughton
Ramp – Protocol used with Cardiopulmonary
stress testing at TBRHSC
Regular Bruce Protocol Stress Test
Stage
Min
MPH
Grade
1
0:00
1.7
10%
2
3:00
2.5
12%
3
6:00
3.4
14%
4
9:00
4.2
16%
5
12:00
5.0
18%
6
15:00
5.5
20%
Modified - Bruce Protocol Stress Test
Stage
Min
MPH
Grade
1
0:00
1.7
0%
2
3:00
1.7
0%
3
6:00
1.7
10%
4
9:00
2.5
12%
5
12:00
3.4
14%
Regular Bruce Protocol Stress Test
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Client preparation
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No caffeine, tobacco, alcohol at least 24 hours
prior to test
May eat a light breakfast
Wear loose comfortable clothing and footwear
appropriate for walking on a treadmill
Regular Bruce Protocol Stress Test
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Instruct client
 That they will be walking on a treadmill that will increase in
speed and incline at regular intervals
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That electrodes be will be applied to the chest wall to
monitor heart rate and the heart’s reaction to exercise
A blood pressure cuff will be placed on the arm and blood
pressure will be monitored at regular intervals
Indications for terminating exercise testing
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Absolute indications:
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Moderate to severe angina
Near syncope, dizziness, ataxia
Cyanosis or pallor
Sustained ventricular tachycardia
Client’s desire to stop
A >10mmHg systolic blood pressure drop from baseline
when accompanied by other signs of ischemia
ST elevation >1mm without diagnostic Q waves
Indications for terminating exercise testing
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Relative Indications
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>10mmHg systolic blood pressure drop from baseline
without other indications of ischemia
>2mm downsloping or horizontal ST depression or marked
axis shift
Arrhythmias other than sustained VT such as
bradyarrhythmias, heart block, supraventricular
tachycardia, multifocal VPB’s or triplets of VPB’s
Wheezing, leg cramps, SOB, fatigue increasing chest pain
Hypertension >250mmHg systolic, >115mmHg diastolic
Negative test
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Heart rate increases linearly with exercise
Systolic blood pressure increases with exercise
Diastolic blood pressure stays the same or
increases or decreases by about 10mmHg
No symptoms of chest discomfort are produced
No horizontal or downsloping ST depression
Test result could be false-negative if the plaque is
an atheromata (inside the wall) or if the plaque that
is protruding into the lumen is less than 75%
Positive stress test
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Horizontal or downsloping ST depression
>1mm (indicative of ischemia)
Limiting symptoms of chest discomfort are
produced
A false-positive stress test could be the result
of a serum electrolyte imbalance, left
ventricular hypertrophy, medications such as
digoxin, mitral valve prolapse
Cardiopulmonary Stress Testing
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Indications for CPX
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Diagnose pulmonary disease
Test modality – cycle ergometry
Expired gasses are directly measured
Ramp protocol – speed and resistance increased
at one minute intervals
Same preparation as for regular stress testing