Clinical exercise testing is used increasingly in clinical practice for two main reasons (Wasserman)-Its impact in the clinical decision-making process -A growing awareness that resting cardiopulmonary measurements do not provide a reliable estimate of functional capacity. The following are the most popular clinical exercise tests, in order of increasing complexity: (a) 6-minute walk test (6MWT), (b) shuttle walk test, (c) exercise-induced bronchoconstriction (EIB), (d) cardiac stress test, and (e) cardiopulmonary exercise test (CPET). The modality is selected on the basis of clinical question to be addressed and the available equipment.
1. CENTER FOR PHYSIOTHERAPY AND
REHABILITATION SCIENCE JAMIA MILLIA ISLAMIA
Topic: Clinical exercise testing: purpose, modalities, protocol
Shagufa Amber
MPT3rd Semester
Roll no.- 19MPC0006
2. Clinical exercise testing is used increasingly in clinical practice for two main
reasons (Wasserman)
-Its impact in the clinical decision-making process
-A growing awareness that resting cardiopulmonary measurements do not
provide a reliable estimate of functional capacity.
The following are the most popular clinical exercise tests, in order of
increasing complexity:
(a) 6-minute walk test (6MWT), (b) shuttle walk test, (c) exercise-induced
bronchoconstriction (EIB), (d) cardiac stress test, and (e) cardiopulmonary
exercise test (CPET). The modality is selected on the basis of clinical question
to be addressed and the available equipment.
3. PURPOSE OF EXERCISE TESTING:
-Exercise testing elicits the body’s reaction to measured increases in acute
exercise. It measures the response of the increase stress upon heart, lungs and
muscles.
-The changes in heart rate, blood pressure, respiration and perceived level of
exercise provide data that permit quantitative estimation of cardiovascular
conditioning and function.
-Exercise tests provide an opportunity to observe a person during exercise.
-By measuring and monitoring heart rate and blood pressure, one can detect
changes in the hemodynamic and ischemic results due to exercise.
Exercise testing - assessment of the integrative exercise responses involving
pulmonary, cardiovascular, haematopoietic, neuropsychological, and skeletal
muscle systems
4. Indications for CPET:
-Evaluation of dyspnea (distinguish cardiac vs pulmonary vs peripheral
limitation vs others , detection of exercise-induced bronchoconstriction
,detection of exertional desaturation)
-Pulmonary rehabilitation ( exercise intensity/prescription ,response to
participation
- Pre-op evaluation and risk stratification
-Prognostication of life expectancy
-Disability determination
-Fitness evaluation
-Confirm the diagnosis
-Assess response to therapy
5. Contraindications to Symptom-Limited Maximal Exercise
Testing (American Heart Association , 2013)
Absolute Contraindications
-Acute myocardial infarction within 2 days.
- Ongoing unstable angina
- Uncontrolled cardiac arrhythmia with hemodynamic compromise
-Active endocarditis
-Symptomatic severe aortic stenosis
-Decompensated heart failure Acute pulmonary embolism, pulmonary
infarction, or deep venous thrombosis
-Acute myocarditis or pericarditis
-Acute aortic dissection
- Physical disability that precludes safe and adequate testing
6. Relative Contraindications
- Known obstructive left main coronary artery stenosis
-Moderate to severe aortic stenosis with uncertain relationship to symptoms -
Tachyarrhythmias with uncontrolled ventricular rates
-Acquired advanced or complete heart block Recent stroke or transient
ischemia attack
-Mental impairment with limited ability to cooperate Resting hypertension
with systolic >200 mm Hg or diastolic >110 mm Hg Uncorrected medical
conditions, such as significant anemia, important electrolyte imbalance, and
hyperthyroidism
7. Maximal exercise tests require participants to exercise to the point of
volitional fatigue, which may be inappropriate for some individuals and may
require the need for emergency equipment .
Exercise professionals rely on submaximal exercise tests to assess CRF
because maximal exercise testing is not always feasible in the health setting.
The foundation of submaximal exercise testing is to determine the HR
response to one or more submaximal work rates and to use the data to
predict an individual’s O2max .
The measurement of HR, blood pressure (BP), work rate, and rating of
perceived exertion (RPE) gives valuable information to the exercise
professional in regard to the patient’s health and functional response to
exercise.
8. Combined with the patient’s estimated O2max , this information can be used
to evaluate and track the patient’s submaximal physiological responses over
time and can be used to make modifications to his or her prescription.
To ensure an accurate estimation of O2max from a submaximal exercise test,
all of the following assumptions must be met or achieved (34):
A steady-state HR is obtained for each exercise work rate.
A linear relationship exists between HR and work rate.
The difference between actual and predicted maximal heart rate (HRmax ) is
minimal. Mechanical efficiency (i.e., O2 at a given work rate) is the same for
everyone.
9. INDICATIONS TO EXERCISE TERMINATION
-Patient’s request: fatigue, dyspnea, pain
-Ischemic ECG changes (2 mm ST depression )
-Chest pain suggestive of ischemia
-Significant ectopy
-2nd or 3rd degree heart block
-SBP >240-250,
-DBP>110-120
-Fall in sbp >20 mmHg
-SpO2 <81-85%
-Dizziness, faintness
-Onset of confusion
-Onset of pallor
10. EQUIPMENTS FOR EXERCISE TESTING:
EXERCISE
EQUIPMENT
TREDMILL
ARM-CRANK
ERGOMETER
CYCLE
ERGOMET
ER
MECHANIC
ALLY
BRAKED
ELECTRICA
LLY
BRAKED
11. CYCLE TREADMILL
VO2 MAX LOWER HIGHER
WORK RATE MEASUREMENT EASIER NO
BLOOD GAS COLLECTION YES MORE DIFFICULT
NOISE AND ARTIFACTS LESS MORE
SAFETY SAFER LESS SAFE?
WEIGHT BEARING IN OBESE LESS MORE
DEGREE OF LEG MUSCLE FATIGUE LESS MORE
MORE APPROPIATE FOR PATIENT ACTIVE NORMAL
SUBJECTS
12. Equipment for airflow and gas measurement
-Airflow or volume transducers
-Pneumotachograph
-Mass flow sensor
-Pitot tube flowmeter
-Turbine volume transducer Gas Analyzer
-Mass spectrometer: measure O2, CO2, N2
-Separate analyzer for O2, CO2
14. Maximal incremental cycle ergometry protocols
-IET protocol
3 minutes of rest, then 3 minutes of unloaded pedalling then the incremental
phase of exercise every minute (5 to 25 W/minute) until the patient reaches
volitional exhaustion or the test is terminated by the medical monitor
-Ramp protocol - increase the work rate continuously, usually every 1 to 2
seconds in a ramplike fashion Standardized exponential exercise protocol
- work rate is increased exponentially by 15% of the previous workload every
minute
15. Maximal incremental treadmill protocols
Bruce protocol
-the starting point (ie, stage 1) is 1.7 mph at a 10% grade (5 METs)
Stage 2 is 2.5 mph at a 12% grade (7 METs).
Stage 3 is 3.4 mph at a 14% grade (9 METs).
This protocol includes 3-minute periods to allow achievement of a steady state
before workload is increased.
Modified Bruce protocol
-2 warm up stages, each lasting 3 minutes.
- The first is at 1.7 mph and a 0% grade,
-The second is at 1.7 mph and a 5% grade
16. Constant work rate protocol
-Treadmill or cycle ergometry exercise at levels approximating the subject’s
usual daily activities (e.g., up to 3.0 mph on a treadmill, or up to 50 W on a
cycle ergometer).
-This test should involve at least 6 minutes of continuous exercise
17. Reference:
Fletcher GF, Ades PA, Kligfield P, et al. Exercise standards for testing and training: a scientific statement from
the American Heart Association. Circulation. 2013;128:873– 934.
Priori, S. G., Wilde, A. A., Horie, M., Cho, Y., Behr, E. R., Berul, C., ... & Kannankeril, P. (2013).
HRS/EHRA/APHRS expert consensus statement on the diagnosis and management of patients with inherited
primary arrhythmia syndromes: document endorsed by HRS, EHRA, and APHRS in May 2013 and by ACCF,
AHA, PACES, and AEPC in June 2013. Heart rhythm, 10(12), 1932-1963.
Patessio, A., Casaburi, R., Carone, M., Appendini, L., Donner, C. F., & Wasserman, K. (1993). Comparison of
gas exchange, lactate, and lactic acidosis thresholds in patients with chronic obstructive pulmonary
disease. American Review of Respiratory Disease, 148, 622-622.
American College of Sports Medicine. (2013). ACSM's guidelines for exercise testing and prescription.
Lippincott Williams & Wilkins.