Exercise Testing

1
Exercise Testing

• Introduction to Cardiology Course
• August 9, 2006
• Eugene E. Wolfel, M.D.

2
Indications for Exercise Testing

• Diagnosis of Coronary Artery Disease
• Assessment of Prognosis in Coronary Artery
  Disease
• Evaluation of Functional Capacity
• Evaluation of Therapy for Coronary Disease
• Determination of Exercise Prescription

3
Absolute Contraindications to Exercise Testing

• Acute MI (within 2 days)
• High-risk unstable angina
• Uncontrolled cardiac arrhythmias
• Active Endocarditis
• Severe aortic stenosis
• Decompensated heart failure
• Acute pulmonary embolus or infarction, DVT
• Acute noncardiac disorder affecting or aggravated
  by exercise
• Acute myocarditis, pericarditis
• Physical disability precludes safe and adequate
  test
• Inability to obtain consent

4
Relative Contraindications to Exercise Testing

• Left main coronary stenosis or equivalent
• Moderate aortic valvular stenosis(?)
• Electrolyte disorder
• Tachyarrhythmias or Bradyarrhythmias
• Atrial fibrillation with uncontrolled ventricular
  response
• Hypertrophic Cardiomyopathy (? gradient)
• Mental impairment leading to inability to
  cooperate
• High-degree AV block

5
ECG Lead Placement for Exercise Testing
6
Protocols for Exercise Testing
7
Blood Pressure Responses Exercise Testing

• Dependency on cardiac output and peripheral
  resistance
• Normal responses
• Increase in SBP ( 20-30 mmHg)
• No change or fall in DBP
• Inadequate rise in SBP
• Myocardial ischemia, severe LV systolic
  dysfunction, aortic or LVOT obstruction, drug
  therapy (ß-blockers)
• Exercise-Induced Hypotension ( 10 mmHg below
  baseline)
• Severe myocardial ischemia (50 positive
  predictive value for left main or 3-vessel
  disease), valvular heart disease, cardiomyopathy
• no evidence of clinically significant heart
  disease (dehydration, antihypertensive therapy,
  prolonged strenuous exercise)

8
Heart Rate Response to Exercise Testing

• Accelerated Heart Rate Response
• Deconditioning, prolonged bed rest, anemia,
  metabolic disorders, conditions associated with
  decreased blood volume or low systemic vascular
  resistance, autonomic insufficency
• Chronotropic incompetence
• Inadequate exercise effort, drug therapy
  (ß-blockers),
• Prognostic Significance
• (Peak HR - Resting HR)/(220-age-Resting HR) 0.80 (Lauer, 1999)
• Peak HR

9
Predicted Values for Exercise Hemodynamics
(Hossack and Bruce, 1980) - Men
10
Predicted Values for Exercise Hemodynamics
(Hossack and Bruce, 1981) - Women
11
Evaluation of Exercise Effort during Exercise
Testing The Borg Perceived Exertion Scale
12
Exercise Capacity - Exercise Testing

• MET capacity
• 1 MET 3.5 ml/kg/min O2 consumption
• Functional Aerobic Impairment (FAI)
• (Bruce Protocol specific)
• Predicted MET level (nomograms)
• Predicted VO2 (ACSM formulae)
• Practical Aspects
• Lack of association between LVEF and exercise
  capacity
• Prognostic value of decreased exercise capacity
  and active CAD
• Predictor of patients disability

13
Exercise Testing - Complications

• MI or death
• Up to 10 per 10,000 tests (1 per 2,500)
• Life threatening ventricular arrhythmias
• 0-5 per 100,000
• Cardiac
• Bradyarrhythmias, tachyarrhythmias, acute
  coronary syndromes, heart failure, hypotension,
  syncope, death
• Noncardiac
• Musculoskeletal trauma, soft-tissue injury
• Miscellaneous
• Severe fatigue, dizziness, myalgias

14
Absolute Indications for Termination of Exercise
Test

• ST-segment elevation ( 1.0 mm) in leads without
  Q-waves (other than V1 or aVR)
• Drop in systolic blood pressure 10 mmHg
  (persistently below baseline) despite an increase
  in workload, when accompanied by any other
  evidence of ischemia
• Moderate to severe angina (grades 3-4)
• Central nervous system symptoms (ataxia,
  dizziness, near syncope)
• Signs of poor perfusion (cyanosis or pallor)
• Sustained ventricular tachycardia
• Technical difficulties monitoring the ECG or
  systolic BP
• Patients request to stop

15
Relative Indications for Termination of an
Exercise Test

• ST changes (horizontal or downsloping 2 mm) or
  marked axis shift
• Drop in systolic blood pressure 10 mmHg
  (persistently below baseline) despite an increase
  in workload, in the absence of other evidence of
  ischemia and no presyncopal symptoms
• Increasing chest pain
• Fatigue, shortness of breath, wheezing, leg
  cramps, or claudication
• Hypertensive response (SBP 250 mmHg and/or DBP
  115 mmHg)
• Development of bundle-branch block (LBBB) that
  cannot be distinguished from ventricular
  tachycardia ? Evidence of anterior ischemia
• Arrhythmias other than sustained ventricular
  tachycardia (frequent multifocal PVCs,
  ventricular triplets, SVT, heart block, or
  bradyarrhythmias)
• General Appearance (diaphoresis, peripheral
  cyanosis)

16
Criteria for Reading ST-Segment Changes on the
Exercise ECG

• ST DEPRESSION
• Measurements made on 3 consecutive ECG complexes
  !
• ST level is measured relative to the P-Q junction
• 3 key measurements (P-Q junction, J-point,
  60-80msec after J-point - use 60 msec for HR
  130 bpm
• When J-point is depressed relative to P-Q
  junction at baseline
• Net difference from the J junction determines
  the amount of deviation
• When the J-point is elevated relative to P-Q
  junction at baseline and becomes depressed with
  exercise
• Magnitude of ST depression is determined from the
  P-Q junction and not the resting J point

17
Criteria for Reading ST-Segment Changes on the
Exercise ECG

• ST ELEVATION
• 60 msec after J point in 3 consecutive ECG
  complexes

18
Criteria for Abnormal and Borderline ST-Segment
Depression on the Exercise ECG

• ABNORMAL
• 1.0 mm or greater horizontal or downsloping ST
  depression at 60 msec after J point on 3
  consecutive ECG complexes
• BORDERLINE
• 0.5 to 1.0 mm horizontal or downsloping ST
  depression at 60 msec after J point on 3
  consecutive ECG complexes
• 2.0 mm or greater upsloping ST depression at 60
  msec after J point on 3 consecutive ECG complexes

19
Morphology of ST-Segment Deviation during
Exercise Testing
20
Value of Right-Sided ECG Leads during Exercise
Testing for the Diagnosis of CAD
21
Horizontal ST-segment Depression during Exercise
Testing
22
Downsloping ST-Segment Depression during Exercise
Testing
23
ST-Segment Depression in Early Recovery Period
after Exercise Testing
24
Upsloping ST-Segment Depression during Exercise
Testing
25
Morphology of ST-Segment Depression Predicts
Severity of Coronary Artery Disease
(Goldschlager, 1976)
26
Exercise-Induced ST-Segment Elevation with Prior
Anterior Myocardial Infarction
27
Exercise-Induced ST-Segment Elevation in the
Setting of Prior Inferolateral MI
28
Exercise-Induced Anterior ST-Segment Elevation as
Reflection of LAD Ischemia
29
Indications for Exercise Testing in the Diagnosis
of Obstructive Coronary Disease

• CLASS I
• Adult patients (including those with RBBB or less
  than 1 mm or resting ST-depression) with an
  intermediate pretest probability of CAD, based on
  gender, age, and symptoms
• CLASS IIa
• Patients with vasospastic angina
• CLASS IIb
• Patients with a high pretest probability of CAD
  by age, symptoms, and gender
• Patients with a low pretest probability of CAD by
  age, symptoms, and gender
• Patients with less than 1 mm of baseline ST
  depression and taking digoxin
• Patients with ECG criteria of LVH and less than 1
  mm St-depression

30
Pre-test Probability of CAD by Age, Gender, and
Symptoms

• Typical/Definite Angina Pectoris
• Age 30-39
• Men Intermediate (10-90)
• Women Intermediate
• Age 40-49
• Men High (90)
• Women Intermediate
• Age 50-59
• Men High
• Women Intermediate
• Age 60-69
• Men High
• Women High

31
Pre-test Probability of CAD by Age, Gender, and
Symptoms

• Atypical/Possible Angina Pectoris
• Age 30-39
• Men Intermediate
• Women Very Low (
• Age 40-49
• Men Intermediate
• Women Low (
• Age 50-50
• Men Intermediate
• Women Intermediate
• Age 60-69
• Men Intermediate
• Women Intermediate

32
Pre-test Probability of CAD by Age, Gender, and
Symptoms

• Nonanginal Chest Pain
• Age 30-39
• Men Low
• Women Very Low
• Age 40-49
• Men Intermediate
• Women Very Low
• Age 50-59
• Men Intermediate
• Women Low
• Age 60-69
• Men Intermediate
• Women Intermediate

33
Pre-test Probability of CAD by Age, Gender, and
Symptoms

• Asymptomatic
• Age 30-39
• Men Very Low
• Women Very Low
• Age 40-49
• Men Low
• Women Very Low
• Age 50-59
• Men Low
• Women Very Low
• Age 60-69
• Men Low
• Women Low

34
Indications for Exercise Testing in the Diagnosis
of Obstructive Coronary Disease

• Class III
• Patients with the following ECG abnormalities
• WPW syndrome, electronically paced ventricular
  rhythm, greater than 1 mm resting ST-depression,
  complete LBBB
• Patients with a documented MI or prior coronary
  angiography demonstrating significant CAD have an
  established diagnosis (?ischemia, prognosis)

35
Exercise Testing Sensitivity and Specificity for
the Diagnosis of CAD

• Sensitivity True positives/true positives
  false negatives x 100
• Specificity True negatives/false positives
  true negatives x 100
• Standard Exercise Test (mostly men)
• Sensitivity 68 Specificity 77
• Predictive Accuracy 73
• Based on 1.0 mm ST-segment depression

36
Exercise Testing in the Diagnosis of Coronary
Artery Disease in Women

• ECG Analysis alone
• Sensitivity 46-79
• Specificity 48-86
• Use of Duke Prognostic Score
• Low Risk score
• 19.1 CAD 75 stenosis, 3.5 3-vessel or left
  main disease
• Intermediate Risk score
• 34.9 CAD 75 stenosis, 12.4 3-vessel or
  left main disease
• High Risk Score
• 89.2 CAD 75 stenosis, 46 3-vessel or
  left main disease

37
Risk Assessment and Prognosis with Exercise
Testing in Patients with Symptoms and Prior
History of CAD

• Class I
• Patient undergoing initial evaluation with
  suspected or known CAD including those with
  complete RBBB and less than 1 mm of resting ECG
  (exceptions - Class IIb)
• Patients with suspected or know CAD previously
  evaluated, now presenting with significant change
  in clinical status
• Low-risk acute coronary syndrome patients 8-12
  hours after presentation who have been free of
  active ischemia or heart failure symptoms (Level
  of EvidenceB)
• Intermediate-risk acute coronary syndrome
  patients 2-3 days after presentation who have
  been free of active ischemia or heart failure
  symptoms (Level of Evidence B)

38
Risk Assessment and Prognosis with Exercise
Testing in Patients with Symptoms and Prior
History of CAD

• Class IIa
• Intermediate-risk acute coronary syndrome
  patients who have initial cardiac markers that
  are normal, a repeat ECG without significant
  change, and cardiac markers 6-12 hours after the
  onset of symptoms that are normal and no other
  evidence of ischemia by observation (Level of
  Evidence B)
• Class IIb
• Patients with the following ECG abnormalities
• WPW syndrome, electronically paced ventricular
  rhythm, 1 mm or more of resting ST-depression,
  complete LBBB or IVCD with a QRS duration 120
  msec
• Patients with a stable clinical course who
  undergo periodic monitoring to guide treatment

39
Risk Assessment and Prognosis with Exercise
Testing in Patients with Symptoms and Prior
History of CAD

• Class III
• Patients with severe co-morbidity likely to limit
  life expectancy and/or candidacy for
  revascularization
• High-risk acute coronary syndrome patients (Level
  of Evidence c)

40
Short-term Risk Assessment for Death or Nonfatal
MI in Patients with Acute Coronary Syndrome

• HIGH RISK (at least one of the following
  features)
• Character of Pain
• Prolonged ongoing (20 min) rest chest pain
• Clinical Features
• Pulmonary edema, new or worsening MR, S3 or
  new/worsening rales, hypotension, bradycardia,
  tachycardia, age 75 yrs
• ECG Findings
• Angina at rest with transient ST changes 0.05
  mV, BBB (new or presumed new), sustained
  ventricular tachycardia
• Biochemical Markers
• Elevated troponin-I

41
Short-term Risk Assessment for Death or Nonfatal
MI in Patients with Acute Coronary Syndrome

• INTERMEDIATE RISK
• No high-risk feature but must have one of the
  following
• History
• Prior MI, peripheral or cerebrovascular disease,
  CABG or prolonged aspirin use
• Character of Pain
• Prolonged ( 20 min) rest angina, now resolved,
  with moderate to high likelihood of CAD
• Rest angina(NTG
• Clinical Findings
• age 70 yrs
• ECG Findings
• T-wave inversions greater than 0.2 mV,
  pathological Q-waves
• Biochemical Markers
• Borderline elevated troponin-I

42
Short-term Risk Assessment for Death or Nonfatal
MI in Patients with Acute Coronary Syndrome

• LOW RISK
• No high or intermediate risk features but any of
  the following
• Character of Pain
• New-onset or progressive CCSC III or IV angina in
  past 2 weeks with moderate to high likelihood of
  CAD
• ECG Findings
• Normal or unchanged ECG during an episode of
  chest discomfort
• Biochemical Markers
• Normal

43
Prognostic Factors from Exercise Testing

• Electrocardiographic
• Maximum ST-depression
• Maximum ST-elevation
• ST-depression slope (morphology)
• Number of leads showing ST changes
• Duration of ST deviation into recovery
• ST/HR indexes
• Exercise-induced ventricular arrhythmias
• Time to onset of ST deviation

44
Prognostic Factors from Exercise Testing

• Hemodynamic
• Maximum exercise heart rate
• Maximum exercise SBP
• Maximum exercise double product (HRxSBP)
• Total exercise duration (functional capacity)
• Exertional hypotension
• Chronotropic incompetence
• Abnormal heart rate recovery

45
Heart Rate Recovery After Exercise Testing
Predicts Outcome in CAD
46
Prognostic Factors from Exercise Testing

• Symptomatic
• Exercise-induced angina
• Exercise-induced symptoms (SOB, dizziness)
• Time to onset of angina

47
Onset and Duration of ST-Segment Depression is
Related to Severity of CAD (Goldschlager, 1976)
48
Prognostic Score in Assessment of Cardiac Event
Risk during Exercise Testing

• Duke Prognostic Score
• Treadmill Score exercise time x 5 (amount of
  ST-segment deviation) - 4 x exercise angina index
  (0 none,
• 1 present but not limiting, 2 reason to
  stop the test)
• High Risk
• Low Risk 5 (0.5 annual mortality)
• Information additive to coronary anatomy and LVEF

49
Duke Prognostic Score Nomogram
50
Combined Prognostic Factors Increase Predictive
Value of Exercise Testing Data in CAD
51
Indications for Exercise Testing after Myocardial
Infarction

• Class I
• Before discharge for prognostic assessment,
  activity prescription, evaluation of medical
  therapy (submaximal versus maximal, submaximal
  4-6 days)
• Early after discharge for prognostic assessment,
  activity prescription, evaluation of medical
  therapy, and cardiac rehabilitation if
  pre-discharge exercise test was not done
  (symptom-limited, about 14-21 days)
• Late after discharge for prognostic assessment,
  activity prescription, evaluation of medical
  therapy, and cardiac rehabilitation if the early
  exercise test was submaximal (symptom-limited 3-6
  weeks)

52
Indications for Exercise Testing after Myocardial
Infarction

• Class IIa
• After discharge for activity counseling and/or
  exercise training as part of cardiac
  rehabilitation in patients who have undergone
  cardiac revascularization
• Class IIb
• Patients with the following ECG abnormalities
• Complete LBBB, Pre-excitation syndrome, LVH,
  Digoxin therapy, greater than 1 mm of resting
  ST-depression, electronically paced ventricular
  rhythm
• Periodic monitoring in patients who continue to
  participate in exercise training or cardiac
  rehabilitation

53
Indications for Exercise Testing after Myocardial
Infarction

• Class III
• Severe comorbidity likely to limit life
  expectancy and/or candidacy for revascularization
• At any time to evaluate patients with acute
  myocardial infarction who have decompensated
  heart failure, cardiac arrhythmias, or noncardiac
  conditions that severely limit their ability to
  exercise (Level of Evidence C)
• Before discharge to evaluate patients who have
  already been selected for, or have undergone,
  cardiac catheterization. Although a stress test
  may be useful before or after catheterization to
  evaluate or identify ischemia in the distribution
  of a coronary lesion of borderline severity,
  stress imaging tests are recommended.

54
Indications for Exercise Testing in Asymptomatic
Persons without Known CAD

• Class I
• None
• Class IIa
• Evaluation of asymptomatic persons with diabetes
  mellitus who plan to start vigorous exercise
  (Level of Evidence C)
• Class IIb
• Evaluation of persons with multiple risk factors
  as a guide to risk reduction therapy (moderate
  Framingham risk score, strongly positive family
  history of premature CAD, ? Calcium score)
• Evaluation of asymptomatic men 45 yrs and women
  55 yrs
• Who plan to start vigorous exercise (especially
  if sedentary) or
• Who are involved in occupations in which
  impairment might impact public safety, or
• Who are at high risk for CAD due to other
  diseases (PAD, Chronic Renal Failure)

55
Indications for Exercise Testing in Asymptomatic
Persons without Known CAD

• Class III
• Routine screening of asymptomatic men or women
• No scientific basis for the executive stress
  test

56
References

• Exercise Standards for Testing and Training.
  Fletcher GF et al. Circulation 2001 104
  1694-1740.
• ACC/AHA 2002 Guideline Update for Exercise
  Testing Summary Article. Gibbons RJ et al.
  Circulation 2002 106 1883-1892.
• ACC/AHA 2002 Complete Guidelines for Exercise
  Testing. Gibbons RJ et al. available at
  Cardiosource.org (ACC) or Americanheart.org (AHA)
• ACC/AHA Clinical Competence Statement on Stress
  Testing. Rodgers GP et al. J. Am. Coll. Cardiol.
  2000 36 1441-1453.