The document provides information on clinical exercise testing procedures and interpretations. It discusses cardiopulmonary exercise testing (CPET) which objectively assesses exercise capacity. CPET allows investigation of the cardiovascular, pulmonary and skeletal muscle systems during exercise. Key variables observed include maximal oxygen uptake and physiological responses to increasing metabolic demand. The document outlines indications, contraindications, testing protocols and how to interpret results including heart rate, blood pressure, electrocardiogram and exercise capacity responses.

1. CENTRE FOR PHYSIOTHERAPY AND REHABILITATION SCIENCES
JAMIA MILLIA ISLAMIA
Submitted to: Dr Jamal Moiz
Submitted by: Sumaiya shams
MPT (cardio)

2. Clinical exercise testing: procedure and interpretation

3. INTRODUCTION
• Cardiopulmonary exercise testing (CPET) is an objective assessment of exercise
capacity. It has become increasingly popular in clinical, research, and athletic
performance settings.
• CPET allows for investigation of the cardiovascular, pulmonary, and skeletal
muscle systems during exercise-induced stress.
• The main variable of maximal oxygen uptake (VO2max) reflects the gold standard
measure of exercise capacity.
• The purpose is to observe physiological responses to increasing or sustained
metabolic demand. The clinical exercise test typically continues until the patient
reaches a sign (e.g., ST-segment depression) or symptom-limited (e.g., angina,
fatigue) maximal level of exertion.
• A clinical exercise test is often referred to as a graded exercise test (GXT), exercise
stress test, or an exercise tolerance test (ETT). When an exercise test includes the
analysis of expired gases during exercise, it is termed a cardiopulmonary exercise
test ( CPET) or exercise metabolic test.
•

4. Indications
• Indications for clinical exercise testing encompass three general categories:
1. diagnosis (e.g., presence of disease or abnormal physiologic response),
2. prognosis (e.g., risk for an adverse event), and
3. evaluation of the physiologic response to exercise (e.g., blood pressure [BP] and
peak exercise capacity). The most common diagnostic indication is the
assessment of symptoms suggestive of IHD.
• The ACC and the American Heart Association recommend a logistic approach to
determining the type of test to be used in the evaluation of someone presenting
with stable chest pain.
• In this approach, a symptom-limited maximal exercise test with
electrocardiographic monitoring only (i.e., without adjunctive cardiac imaging)
should initially be considered when the diagnosis of IHD is not certain, the patient
has an interpretable resting electrocardiogram (ECG)

5. Recommendations Regarding the Utility of Clinical Exercise Testing
among Patients with Heart Disease
1. Patients with ST-Segment Elevation Myocardial Infarction (STEMI)
Recommendation: : “Noninvasive testing for ischemia should be performed before
discharge to assess the presence and extent of inducible ischemia in patients with
STEMI who have not had coronary angiography and do not have high-risk clinical
features for which coronary angiography would be warranted.”
Comment: “Exercise testing early after STEMI may also be performed to
(a) assess functional capacity and the ability to perform tasks at home and at work,
(b) evaluate the efficacy of medical therapy, and
(c) assess the risk of a subsequent cardiac event. Symptom-limited exercise testing is a
key feature of the intake evaluation for enrollment in a program of cardiac
rehabilitation ≥2 wk after discharge.”

6. 2. Risk Stratification before Discharge in the Absence of Invasive Intervention in
Patients with Non–ST-Segment Elevation (NSTE) Acute Coronary Syndrome
Recommendation: “Noninvasive stress testing is recommended in low and
intermediate-risk patients who have been free of ischemia at rest or with low-level
activity for a minimum of 12 to 24 hours.”
Recommendation: “Low-level or symptom-limited treadmill exercise testing is useful
in patients able to exercise in whom the ECG is free of resting ST changes that may
interfere with interpretation.”
Comment: “Low- and intermediate-risk patients with NSTE-ACS may undergo
symptom-limited stress testing, provided they have been asymptomatic and clinically
stable at 12 to 24 hours for those with unstable angina and 2 to 5 days for patients at
similar risk with NSTEMI.”

7. 3. Ischemic Heart Disease (IHD)
• Indication: Initial diagnosis of suspected IHD
• Recommendation: “Standard exercise ECG testing is recommended for patients
with an intermediate pretest probability of IHD who have an interpretable ECG and
at least moderate physical functioning or no disabling comorbidity.”
• Recommendation: “Standard exercise ECG testing is not recommended for
patients who have an uninterpretable ECG or are incapable of at least moderate
physical functioning or have disabling comorbidity.”
• Indication: Risk assessment in patients with stable IHD
• Recommendation: “Standard exercise ECG testing is recommended for risk
assessment in patients with [stable IHD] who are able to exercise to an adequate
workload and have an interpretable ECG.”
• Indication: Diagnostic assessment in symptomatic patients with known stable IHD
• Recommendation: “Standard exercise ECG testing is recommended in patients
with known stable IHD who have new or worsening symptoms not consistent with
unstable angina and who have (a) at least moderate physical functioning and no
disabling comorbidity and (b) an interpretable ECG.”
• Indication: Prognosis and exercise prescription in patients with stable IHD
• Recommendation: “For all patients, risk assessment with a physical activity
history and/or an exercise test is recommended to guide prognosis and
prescription.”

8. 4. Preoperative Cardiovascular Evaluation
• Recommendation: “For patients with elevated risk and unknown functional
capacity, it may be reasonable to perform exercise testing to assess for functional
capacity if it will change management.”
• Recommendation: “Routine screening with noninvasive stress testing is not useful
for patients at low risk for non cardiac surgery.”
• Recommendation: “Cardiopulmonary exercise testing may be considered for
patients undergoing elevated risk procedures in whom functional capacity is
unknown.”
• Recommendation: “Routine screening with noninvasive stress testing is not useful
for patients undergoing low-risk non cardiac surgery.”

9. 5. : Adults With Chronic Heart Failure (HF)
Recommendation: “Maximal exercise testing with or without measurement of
respiratory gas exchange and/or blood oxygen saturation is reasonable in patients
presenting with HF to help determine whether HF is the cause of exercise limitation
when the contribution of HF is uncertain.”
Recommendation: “Maximal exercise testing with measurement of respiratory gas
exchange is reasonable to identify high-risk patients presenting with HF who are
candidates for cardiac transplantation or other advanced treatments.”
Recommendation: “Exercise testing should be considered in patients with HF:
(i) To detect reversible myocardial ischemia
(ii) As part of the evaluation of patients for heart transplantation and mechanical
circulatory support;
(iii) To aid in the prescription of exercise training;
(iv) To obtain prognostic information.”

10. 6. Percutaneous Coronary Intervention (PCI)
• Recommendation: “In patients entering a formal cardiac rehabilitation program
after PCI, treadmill exercise testing is reasonable.”
• Recommendation: “Routine periodic stress testing of asymptomatic patients after
PCI without specific clinical indications should not be performed.

11. 7. Valvular Heart Disease (VHD)
• Recommendation: “Exercise testing is reasonable in selected patients with asymptomatic
severe VHD to 1) confirm the absence of symptoms, or 2) assess the hemodynamic response
to exercise, or 3) determine prognosis.”
• Recommendation: “Exercise testing is reasonable to assess physiological changes with
exercise and to confirm the absence of symptoms in asymptomatic patients with a calcified
aortic valve and an aortic velocity 4.0 m per second or greater or mean pressure gradient 40
mm Hg or higher .”
• Recommendation: “Exercise testing should not be performed in symptomatic patients with
AS when the aortic velocity is 4.0 m per second or greater or mean pressure gradient is 40
mm Hg or higher .
• Recommendation: “Exercise testing with Doppler or invasive hemodynamic assessment is
recommended to evaluate the response of the mean mitral gradient and pulmonary artery
pressure in patients with mitral stenosis when there is a discrepancy between resting Doppler
echocardiographic findings and clinical symptoms or signs.”
• Recommendation: “Exercise hemodynamics with either Doppler echocardiography or
cardiac catheterization is reasonable in symptomatic patients with chronic primary MR where
there is a discrepancy between symptoms and the severity of MR at rest.
• Recommendation: “Exercise testing may be considered for the assessment of exercise
capacity in patients with severe TR with no or minimal symptoms.
• Recommendation: “Exercise testing is reasonable in asymptomatic patients with severe AS
or severe valve regurgitation before pregnancy.”

12. Contraindications
Absolute Contraindications
• Acute myocardial infarction within 2 d
• 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

13. 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

14. Testing Mode and Protocol

16. Indications for Terminating a Symptom-Limited Maximal Exercise Test
Absolute Indications
• ST elevation (>1.0 mm) in leads without preexisting Q waves because of prior MI
• Drop in systolic blood pressure of >10 mm Hg, despite an increase in workload,
when accompanied by other evidence of ischemia
• Moderate-to-severe angina
• Central nervous system symptoms (e.g., ataxia, dizziness, or near syncope)
• Signs of poor perfusion (cyanosis or pallor)
• Sustained ventricular tachycardia or other arrhythmia, including second- or third-
degree atrioventricular block, that interferes with normal maintenance of cardiac
output during exercise
• Technical difficulties monitoring the ECG or systolic blood pressure
• The subject’s request to stop

17. Relative Indications
• Marked ST displacement (horizontal or downsloping of >2 mm, measured 60 to 80
ms after the J point in a patient with suspected ischemia)
• Drop in systolic blood pressure >10 mm Hg (persistently below baseline) despite
an increase in workload, in the absence of other evidence of ischemia
• Increasing chest pain
• Fatigue, shortness of breath, wheezing, leg cramps, or claudication
• Arrhythmias other than sustained ventricular tachycardia, including multifocal
ectopy, ventricular triplets, supraventricular tachycardia, and bradyarrhythmias that
have the potential to become more complex or to interfere with hemodynamic
stability
• Exaggerated hypertensive response (systolic blood pressure >250 mm Hg or
diastolic blood pressure >115 mm Hg)
• Development of bundle-branch block that cannot be distinguished from ventricular
tachycardia
• SpO2 ≤80%

18. Postexercise
• The sensitivity of the exercise test for the diagnosis of IHD can be maximized when
the patient is placed in a seated or supine position immediately following exercise.
Therefore, if the primary indication of the test is suspected IHD and nonsignificant
repolarization changes are observed at peak exercise, then immediate supine
recovery without active recovery should be considered.
• However, exercise cessation can cause an excessive drop in venous return resulting
in profound hypotension during recovery and ischemia secondary to decreased
perfusion pressure into the myocardium.
• Therefore, continuation of low-intensity active recovery during the postexercise
period is often practiced in order to support venous return and hemodynamic
stability.
• Each laboratory should develop standardized procedures for the postexercise
recovery period (active vs. inactive and monitoring duration) with the laboratory’s
medical director that considers the indication for the exercise test and the patient’s
status during the test.

19. INTERPRETING THE CLINICAL EXERCISE TEST
1. Heart Rate Response
• The normal HR response to incremental exercise is to increase with increasing workloads at a
rate of ≈10 beats · min −1 per 1 MET.
• HRmax decreases with age and is attenuated in patients on β-adrenergic blocking agents.
Several equations have been published to predict HRmax in individuals who are not taking a
β-adrenergic blocking agent.
• All estimates have large interindividual variability with standard deviations of 10 beats or
more.
• Among patients referred for testing secondary to IHD and in the absence of βadrenergic
blocking agents, failure to achieve an age-predicted HRmax ≥85% in the presence of maximal
effort is an indicator of chronotropic incompetence and is independently associated with
increased risk of morbidity and mortality.
• An abnormal chronotropic response provides prognostic information that is independent of
myocardial perfusion. The combination of a myocardial perfusion abnormality and an
abnormal chronotropic response suggests a worse prognosis than either abnormality alone.
• A failure of the HR to decrease by at least 12 beats during the first minute or 22 beats by the
end of the second minute of active postexercise recovery is strongly associated with an
increased risk of mortality in patients diagnosed with or at increased risk for.
• The failure of HR to recover adequately may be related to the inability of the parasympathetic
nervous system to reassert vagal control of HR, which is known to predispose individuals to
ventricular dysrhythmias

20. 2. Blood Pressure Response
• The normal systolic blood pressure (SBP) response to exercise is to increase with
increasing workloads at a rate of ~10 mm Hg per 1 MET.
• On average, this response is greater among men; increases with age; and is
attenuated in patients on vasodilators, calcium channel blockers, angiotensin-
converting enzyme inhibitors, and α- and β-adrenergic blockers.
• An SBP >250 mm Hg is a relative indication to stop a test. An SBP ≥210 mm Hg in
men and ≥190 mm Hg in women during exercise is considered an exaggerated
response.
• A decrease of SBP below the pretest resting value or by >10 mm Hg after a
preliminary increase, particularly in the presence of other indices of ischemia, is
abnormal and often associated with myocardial ischemia, left ventricular
dysfunction, and an increased risk of subsequent cardiac events.
• Blunted response: In patients with a limited ability to augment cardiac output , the
response of SBP during exercise will be slower compared to normal.
• Postexercise response: SBP typically returns to pre exercise levels or lower by 6
min of recovery. Studies have demonstrated that a delay in the recovery of SBP is
highly related both to ischemic abnormalities and to a poor prognosis.

21. 3. Rate-Pressure Product
• Rate-pressure product is calculated by multiplying the values for HR and SBP that
occur at the same time during rest or exercise.
• There is a linear relationship between myocardial oxygen uptake and both coronary
blood flow and exercise intensity.
• Coronary blood flow increases due to increased myocardial oxygen demand as a
result of increases in HR and myocardial contractility.
• If coronary blood flow supply is impaired, which can occur in obstructive IHD,
then signs or symptoms of myocardial ischemia may be present.
• The point during exercise when this occurs is the ischemic threshold.

22. 4. Electrocardiogram
• The normal response of the ECG during exercise includes the following:
• P-wave: increased magnitude among inferior leads
• PR segment: shortens and slopes downward among inferior leads
• QRS: Duration decreases, septal Q-waves increase among lateral leads, R waves
decrease, and S waves increase among inferior leads.
• J point: depresses below isoelectric line with upsloping ST segments that reach the
isoelectric line within 80 ms
• T-wave: decreases amplitude in early exercise, returns to preexercise amplitude at
higher exercise intensities, and may exceed preexercise amplitude in recovery
• QT interval: Absolute QT interval decreases. The QT interval corrected for HR
increases with early exercise and then decreases at higher HRs.
• ST-segment changes (i.e., depression and elevation) are widely accepted criteria for
myocardial ischemia and injury.

23. Exercise Capacity
• A high exercise capacity is indicative of a high peak and therefore suggests the absence of
serious limitations of left ventricular function.
• several studies have been demonstrating the importance of exercise capacity relative to the
prognosis of patients with heart failure or cardiovascular disease. Either absolute or age- and
gender normalized exercise capacity is highly related to survival.
• A significant issue relative to exercise capacity is the imprecision of estimating exercise
capacity from exercise time or peak workload.
• The standard error in estimating exercise capacity from various published prediction
equations is at least ±1 MET. This measurement error is less meaningful in young, healthy
individuals with a peak exercise capacity of 13–15 METs (7%– 8% error) but more significant
in individuals with reduced exercise capacities typical of those observed in patients with
cardiac or pulmonary disease (4–8 METs; 13%–25% error).
• Estimating exercise capacity on a treadmill is confounded when patients use the handrail for
support which will result in an overestimation of their exercise capacity . Although equations
exist to predict exercise capacity from an exercise test using handrail support, the standard
error of the estimate remains large. Safety of treadmill walking is always an important
consideration, and allowing a patient to use the handrail should be determined on a case-by-
case basis.

24. Maximal versus Peak Cardiorespiratory Stress
When an exercise test is performed as part of the evaluation of IHD, patients should be
encouraged to exercise to their maximal level of exertion or until a clinical indication to
stop the test is observed. Various criteria have been used to confirm that a maximal
effort has been elicited during a GXT:
• A plateau in O2 (or failure to increase O2 by 150 mL · min −1 ) with increased
workload . This criterion has fallen out of favor because a plateau is not
consistently observed during maximal exercise testing with a continuous protocol.
• Failure of HR to increase with increases in workload
• A postexercise venous lactate concentration >8.0 mmol · L −1
• A rating of perceived exertion (RPE) at peak exercise >17 on the 6–20 scale or >7
on the 0–10 scale.
• A peak RER ≥1.10. Peak RER is perhaps the most accurate and objective
noninvasive indicator of subject effort during a GXT.

25. DIAGNOSTIC VALUE OF EXERCISE TESTING FOR THE
DETECTION OF ISCHEMIC HEART DISEASE
The factors that determine the diagnostic value of exercise testing are the sensitivity
and specificity of the test procedure and prevalence of IHD in the population tested:
1. Sensitivity refers to the ability to positively identify patients who truly have IHD.
• Exercise ECG sensitivity for the detection of IHD has traditionally been based on
angiographic evidence of a coronary artery stenosis ≥70% in at least one vessel.
• The sensitivity of an exercise test is decreased by inadequate myocardial stress,
medications that attenuate the cardiac demand to exercise or reduce myocardial
ischemia (e.g., β-adrenergic blockers, nitrates, calcium channel blocking agents),
and insufficient ECG lead monitoring.
2. Specificity refers to the ability to correctly identify patients who do not have IHD.
Reported values for the specificity and sensitivity of exercise testing with ECG only
vary because of differences in disease prevalence, test protocols, ECG criteria for a
positive test, and the angiographic definition of IHD

26. Clinical Exercise Test Data and Prognosis
• The most widely accepted and used of these prognostic scores is the Duke
Treadmill Score or the related Duke Treadmill Nomogram . Both are appropriate
for patients with or without a history of IHD being considered for coronary
angiography without a history of a MI or revascularization procedure.
• The Duke Score/Nomogram considers exercise capacity, the magnitude of ST-
segment depression, and the presence and severity of angina pectoris.
• The calculated score is related to annual and 5-yr survival rates and allows the
categorization of patients into low-, moderate-, and high-risk subgroups. This
categorization may help the physician choose between more conservative or more
aggressive therapies.
• Physicians may also use prognosis estimates based other hemodynamic findings,
such as chronotropic incompetence or an abnormal HR recovery, to guide their
clinical decision.

27. FIELD WALKING TESTS
• The traditional sign/symptom-limited, maximal exercise test with ECG monitoring
that is performed in a clinical laboratory, often with a treadmill or cycle ergometer.
• However, non–laboratory-based clinical exercise tests are also frequently used in
patients with chronic disease.
• These are generally classified as field or hallway walking tests and are typically
considered submaximal. Similar to maximal exercise tests, field walking tests are
used to evaluate exercise capacity, estimate prognosis, and evaluate response to
treatment.
• The most common among the field walking tests is the 6-min walk test (6MWT),
but evidence has been building for other field walking tests, such as the incremental
and endurance shuttle walk tests.
• The 6MWT was originally developed to assess patients with pulmonary disease
however, it has been applied in various patient groups and is a popular tool to assess
patients with heart failure.
• The advantages of field walking tests are the simplicity and minimal cost, often
requiring just a hallway. In addition, because the patient walks at a selfselected
pace, a field walking test might be more representative of a patient’s ability to
perform activities of daily living.

29. THANK YOU!!