Transcript Considerations for Exercise Testing & Prescription: Cardiac Population

Considerations for Exercise Testing
& Prescription: Cardiac Population
Cardiac Wellness
Institute of Calgary
Updated May 2010
Material to be Covered

ACSM’s Resource Manual for Guidelines for
Exercise Testing and Prescription ‘R’ (6th
Edition):
– Chapters 10, 18, 21, 22, 27, 35

ACSM’s Guidelines For Exercise Testing And
Prescription ‘G’ (8th Edition):
– Chapters 2, 3, 5, 6, 7, 9
– Appendix C

ACSM’s Clinical Certification Review (3rd
Edition)
Health Appraisal, Risk
Assessment & Safety of
Exercise
Guidelines - Chapter 2
Resource Manual - Chapter 10
Pre-Screening
 Rationale
– Identify and exclude those with contraindications
– Identify those at risk for or have CVD, PD & MD and
should participate in supervised exercise
– Detection of individuals at increased risk for disease
because of age, symptoms, risk factors who should
undergo further evaluation
– Recognize special needs that influence testing and
programming procedures
 Figure
2.3-G: Logic model for risk stratification
– Aids in determining risk stratification and the need for
medical clearance
Pre-Screening
 Self
Administered Screening:
– PAR-Q (Figure 2.1-G)
– AHA/ACSM Health Fitness Preparticipation Screening
questionnaire (Figure 2.2-G)
 Professionally
Guided Screening
– Review of detailed medical history and specific risk
stratification (table 2.1-2.3-G)
– Detailed recommendations for physical activity,
medical examination, exercise testing, and physician
supervision
Initial ACSM Risk
Stratification
 Table
2-1 (p.23-G):
– Low risk: Asymptomatic men and women who have
≤1 CVD risk factor from table 2.3
– Moderate risk: Asymptomatic men and women who
have ≥2 risk factors from table 2.3
– High risk: Known CVD, PD, or MD or one or more
signs or symptoms from table 2.2
Case Study
Risk Stratification

35 year old normotensive asymptomatic male

Exercises 3X/wk

LDL 2.8mmol/L HDL 1.1mmol/L

Continues to smoke 1pack/day even though his
father died of MI at 40
Risk stratification: MODERATE
Case Study
Risk Stratification

49 year old hypertensive sedentary female

WC = 105cm

Total cholesterol = 5.7mmol/L HDL=0.6mmol/L

Shortness of breath at rest, exacerbated by
ADL’s
Risk stratification: HIGH
Case Study
Risk Stratification

45 year old non smoking male

Exercising 5X/wk

Total cholesterol = 4.2mmol/L

BMI = 23.4kg/m2

Resting BP = 110/68mmHg
Risk stratification: MODERATE
Risk Stratification for
Cardiac Patients
Box 2.3-G (AACVPR)
Box 2.2-G (AHA)
Low Risk Stratification for
Cardiac Patients (AACVPR) Box 2.3-G

Exercise test findings (All must be present):

Normal hemodynamics with exercise & recovery

Absence of complex ventricular dysrhythmias
with exercise or recovery

Asymptomatic with absence of AP with exercise
or recovery

Functional capacity  7METs
Low Risk Stratification for
Cardiac Patients Cont’d (AACVPR)
 Non-exercise
 LVEF
 No
test findings:
 50%
resting complex ventricular dysrhythmias
 Uncomplicated
 Absence
MI or revasc procedure
of CHF
 Absence
of signs and symptoms of postevent/post-procedure ischemia
 Absence
of clinical depression
Moderate Risk Stratification
Exercise
test findings (One or more):
− Presence
of angina or other significant
symptoms
− Mild
to moderate level of silent ischemia
during test or recovery

ST depression <2mm from baseline
− Functional
capacity <5 METs
− Non-exercise
− Rest
test findings:
LVEF 40 - 49%
High Risk Stratification
 Exercise
test findings:
−
Complex dysrhythmias with exercise or recovery
−
Presence of angina or other significant symptoms at low
levels of exertion
−
Presence of abnormal hemodynamics with exercise &
recovery
−
High level of silent ischemia during test or recovery

ST depression >2mm from baseline
High Risk Stratification
 Non-exercise
test findings:
−
Rest LVEF 40%
−
History of cardiac arrest or sudden death
−
Complex dysrhythmias at rest
−
Complicated MI or cardiac surgery
−
Presence of CHF
−
Signs and symptoms of post-event/post-procedure
ischemia
−
Presence of clinical depression
AHA Risk Stratification
Box 2.2-G
 Cardiac
patients (Classes B,C,D):
– Class B: presence of known, stable CVD with low
risk for complications with vigorous exercise, but
slightly greater than for apparently healthy
– Class C: moderate to high risk for cardiac
complications during exercise and/or unable to selfregulate activity or understand recommended activity
level
– Class D: unstable disease with activity restriction
AHA Risk Stratification

Provides:
– Diagnoses
– Clinical characteristics
– Activity guidelines
– Supervision required
– EKG and BP monitoring recommendations

Does not consider comorbidities
Exercise Testing
Guidelines - Chapters 3, 5 & 6
Resource Manual - Chapters 18, 21 & 22
Pre-Test Evaluation

Medical history (Box 3.1-G)

Physical exam (MD) (Box 3.2-G)

Laboratory tests by level of risk (Box 3.3-G)

Blood pressure evaluation (Table 3.1G)
– SBP 120mmHg; DBP 80mmHg

Cholesterol targets (Table 3.2-G)
Contraindications to Exercise
Testing

Box 3.5-G Risk: Benefit ratio

Absolute contraindications
– Not to be tested until condition(s) stabilize/treated
– May not apply post MI

Relative contraindications
– Careful evaluation risk/benefit ratio

Non-diagnostic tests – LBBB, LVH
– Testing useful for exercise prescription purposes,
assess hemodynamic response, arrhythmia
Pre-Test Procedures
 Obtain
informed consent
 Patient
instructions
– No food, alcohol, caffeine, tobacco for 3 hours
– Adequate rest
– Accompaniment
– Clothing recommendations
– Diagnostic tests: no meds
– Non-diagnostic tests: on meds
– List of medications
– Ample fluids
Clinical Exercise Testing
 Diagnostic
exercise testing
– Age and gender
– Symptomatic individuals
– Asymptomatic: when multiple RF present
– Starting vigorous exercise program
– Occupational setting
 Assess
disease severity & prognosis
 Post
MI to make decisions about therapy &
safety in performing ADL’s
 Functional
Testing
Clinical Exercise Testing
Other Considerations

Modality

Protocol

HR & BP measurement during test

EKG monitoring

RPE, Dyspnea, Anginal scales

Gas exchange & ventilatory responses

Blood gases

Frequency for monitoring (Table 5-2)

Indications for termination (Box 5-2)

Post Exercise Period
Clinical Exercise Testing
Other Considerations
 Supervision
– Expect acute MI & cardiac arrest to occur at
combined rate of 1/2500 tests
– Physician supervised (or immediately available), with
experienced medical support & supplies to deal with
emergency
– Cognitive skills to supervise tests (Box 5-3)
Exercise Testing with Imaging
Resource - Chapter 22
Guidelines - Chapter 5

Exercise Echocardiography

Exercise Nuclear Imaging

Pharmacological Stress Testing

Electron Beam Computed Tomography
Interpretation of Clinical Test
Data

Purpose: Diagnosis vs Prognosis
– Quantitative measure of:


Exercise tolerance (VO2 peak)

Hemodynamics (SBP, DBP, HR)

Associated change(s) in heart function (EKG)

Limiting clinical s/s

Gas exchange and ventilatory responses
Clinical significance (Box 6-1)
ECG Responses to
Exercise Testing
Guidelines - Appendix C, Chapter 6
Resource - Chapter 27
EKG Waveforms
Normal Responses with Exercise
 Minor
change in P wave morphology
P
& T superimposing in successive beats

Q wave amplitude in septal leads
 Slight
 R wave amplitude
Cont’d

T wave amplitude
 Minimal
J
shortening of QRS duration
point depression
 Rate-related
interval
shortening of QT
Abnormal EKG Responses
ST Segment Displacement

ST Elevation
– May be seen in normal ECG (early repol.) and
decreases with increased HR
– Ex-induced in leads with Q wave infarction may be
indicative of wall motion abnormality, ischemia, or
both
– In otherwise N EKG: elevation represents significant
ischemia & localizes the ischemia to area in
myocardium
Abnormal EKG Responses
ST Segment Displacement
Abnormal EKG Responses
ST Segment Displacement

ST segment depression
– Most common manifestation of ischemia
– Horizontal or downsloping more indicative of
ischemia than upsloping
– Positive test 1mm or horizontal or down sloping
80msec after j-point
– Slowly upsloping = borderline response
Cont’d
 ST
segment depression
– Does not localize areas of ischemia nor indicate
which coronary artery is involved
– More leads with  = more severe disease
– If change is only in recovery it is a true positive
response, important diagnostic finding
– LBBB: uninterpretable for ST change
– RBBB: V4, V5, V6, II, III, aVF used for interpretation,
V1, V2, V3 uninterpretable
Abnormal EKG Responses
ST Segment Normalization/No change

EKG abnormal at rest:
– T wave inversion
– ST-segment depression

May return to normal during anginal symptoms
or during exercise
Abnormal EKG Responses
Dysrhythmias

Potential mechanisms
–  Sympathetic drive
–  in pH
–  extra & intracellular electrolytes
– O2 tension

Mechanisms contribute to circuit re-entry,
enhanced automaticity, and triggered activity
(Box 27-2)
Abnormal EKG Responses
Supraventricular Dysrhythmias

Premature Atrial complexes (PAC):
– Premature beat with a narrow QRS produced from
atrial site other than SA node, are not of concern
when isolated

Atrial/Supraventricular tachycardia:
– Any dysrhythmia originating above AV node.
Mechanisms found on pg 433/434

Atrial fibrillation/flutter (Pg 433)
Dysrhythmia
Supraventricular Tachycardia
Abnormal EKG Responses
Ventricular Dysrhythmias

Premature Ventricular Complexes (PVC):
– beats produced from site in ventricle before next
wave of depolarization from SA node
– Have wide QRS complex and may occur in various
combinations (Box 27-3)

Ventricular Tachycardia (VT)
– 3 or more consecutive PVCs at a rate of 100+
– Sustained= > 30 sec, Nonsustained= < 30 sec

Torsades de Pointes, Vent Fibrillation (Pg 436)
Dysrhythmias
Ventricular Tachycardia (VT)
Dysrhythmia Criteria for Test
Termination

Absolute:
– Sustained ventricular tachycardia

Relative:
– Multifocal PVCs, triplets, SVT, heart block,
bradyarrhythmias
– Development of bundle branch block that cannot be
distinguished from VT
Heart Rate Response to
Exercise Testing
(Guidelines - Chapter 6)
 Linear
- 10  2bpm/MET
 Chronotropic
Incompetence
– Inability to appropriately increase HR during exercise
– Peak HR 20 bpm < Age- predicted HR max (doesn’t
apply to those on Beta Blockers)
 HR
Recovery at 1 minute is abnormal if < 12
bpm decrease in first minute
SBP Response to Exercise
Testing (Box 6.1-G)

Normal response
– 10  2mmHg/MET; may plateau at peak

Termination criteria:
– SBP  250mmHg
– Fails to rise or fall 10mmHg

Sign of ischemia or poor LV function

<140 mmHg at max = poor prognosis
DBP Response to Exercise
Testing (Box 6.1-G)
 Normal
response:
– No  or decrease
 Termination
–
criteria
>115 mm Hg
Anginal Symptoms During
Exercise Testing (Box 6.1-G)
ANGINAL SCALE
1+ Mild, barely noticeable
2+ Moderate, bothersome
3+ Moderately severe, very uncomfortable*
4+ Most severe or intense pain ever experienced*
*Test termination criteria
Gas Exchange and Ventilatory
Responses (Guidelines- 6)
 Used
to index patient effort during test
 Provides
important information about CV fitness
& prognosis
 Estimate
anaerobic/lactate threshold
– Helps avoid metabolic acidosis, hyperventilation and
reduced capacity to perform work
Exercise Prescription for
Cardiac Patients
Guidelines – Chapter 9
Resource manual – Chapter 35
Exercise Prescription for
Cardiac Patients

Inpatient (Guidelines- Chapter 9)
– Early assessment and mobilization
– Identification and education of risk factors
– Assessment of pt. readiness for activity
– Discharge planning

Outpatient
– Develop safe exercise program
– Provide appropriate supervision
– Return patient to normal activities and assist in modifying
daily activities where necessary
– Secondary prevention and risk factor modification
Exercise Prescription
Outpatient Cardiac Patients

Risk stratification according to Boxes 2.3
(AACVPR), 2.2 (AHA) p. 30 -33

No contraindications to exercise (Guidelines Box
9.2, p.209)

Patients without exercise test
– Conservative risk strat & exercise prescription
Exercise Prescription
Outpatient Cardiac Patients
 Design
considerations
– Safety factors

Clinical status
 Risk strat
 Exercise capacity

Ischemic/anginal threshold
 Cognitive/Psych impairment
– Vocation & avocational requirements
– Orthopedic limitations
– Pre-morbid and current activities
– Personal health & fitness goals
Exercise dosage determination
Duration & frequency
Chapter 9 - Guidelines

Frequency

Intensity

Time

Type
Frequency

Most days of the week (4-7)

For those with limited exercise capacities,
multiple short sessions (<10min) are
recommended

Participants should be encouraged to do some
exercise session independently (without
supervision)
Intensity

Various methods can be used to prescribe intensity:

Rating of perceived exertion (RPE), 6-20 scale
– Early rehab upper limit: 11-13 (fairly light to somewhat
hard)
– Progress to 14-16 if asymptomatic
– High inter-individual variability
– Used with the Talk Test (CWIC)

40-80% of exercise capacity using HR reserve or
Karvonen method if maximal exercise data is available.
– Use table 9.1-G when no data is available
– This method necessitates a HR monitor
FITT Intensity
Other Considerations
 THR
always 10bpm below:
– 1mm horizontal or downsloping ST segment 
– Anginal symptoms or other CV insufficiency
– SBP 250mmHg, plateau SBP or SBP
– DBP 115mmHg
FITT Intensity
Other Considerations
 THR
always 10bpm below:
–  frequency ventricular arrhythmias
– Other significant EKG disturbances
– Radionuclide evidence LV dysfunction
– Mod/sev wall motion abnormality with ex
– Other s/s of intolerance
– Consider timing of medication
Time

Warm-up/Cool-down activities should last 5-10
minutes each

Aerobic conditioning= 20-60minutes is goal
– May have to start with multiple short bouts
– Increase time by 10-20% per week, as per
patient tolerance
Same as Table 9.2-G in the eighth edition
Type

Large-muscle-group aerobic activities,
emphasizing caloric expenditure

Include upper and lower extremities

Variety of activities

Use of various exercise equipment
– Arm ergometer, cycle ergometer, elliptical, rower,
stair climber, treadmill
Progression From Medical
Supervision to Independent Exercise
 Ideally,
most should participate in supervised
program to facilitate exercise & lifestyle changes
 Criteria
for independent exercise:
– Cardiac symptoms stable/absent
– Stable ECG, BP, HR responses
– Knowledge of exercise principles, symptom
management
– Motivation
Resistance Training in
Cardiac Patients
Guidelines - Chapter 9
 Meet
eligibility criteria (Box 9.7)
 Type:
– Elastic bands, light free weights (1-5lb), wall pulleys,
machines
 Technique:
– Slow, controlled movements
– Regular breathing pattern (no holding)
– Avoid sustained, tight grip
– RPE 11-13
– Monitor symptoms
Prescription Guidelines: RT

2-4 sets/muscle group, 12-15 reps, 8-10
exercises

2-3 days/week

Exhale on exertion

Increase weight 2-5lbs/wk (arms), 5-10lbs/wk
(legs)
Special Patient Populations
Guidelines - Chapter 9
Resource Manual - Chapter 35
Special Patient Populations
Angina or Silent Ischemia

Ischemia – inadequate blood flow to meet myocardial
oxygen demand
– Generally result of critical lesion > 70%

Angina – pain associated with ischemia

Silent Ischemia – no pain associated with ischemic
threshold (EKG changes)

Goal of training:
–  anginal & ischemic threshold by decreasing
myocardial oxygen demand at any given submax
exertion
Special Patient Populations
Angina or Silent Ischemia
 Prescription
guidelines:
– Prolonged WU & CD
– THR  10bpm below ischemic threshold
 Other
possible strategies:
– Pre-ex nitroglycerin
– Intermittent, shorter duration ex on frequent basis
 NTG
protocol
 Know
signs and symptoms
Special Patient Populations:
Congestive Heart Failure

Inability of heart to deliver blood d/t impairment
in cardiac output

Classic symptoms are exercise intolerance or
dyspnea on exertion

30-40% lower exercise capacity than healthy
individuals

Intensity: 40/50%-70% Heart Rate Reserve
(HRR)

May need to start with short bouts
Dyspnea Scale
+1 Light, barely noticeable
+2 Moderate, bothersome
+3 Moderately severe, very uncomfortable
+4 Most severe or intense dyspnea ever
experienced
Dyspnea Scale
Nothing
0
Severe
5
Very, very slight
0.5
Very slight
1
Slight
2
8
Moderate
3
9
Somewhat severe
4
6
Very severe
Very, very severe
7
10
Special Patient Populations
ICD

Manage tachydysrhythmias with burst pacing or
shock

Know cutoff rate

At risk of receiving inappropriate shocks during
exercise if HR exceeds programmed threshold
or pt develops ex-induced SVT

Closely monitor with EKG, pulse palpation to
safely up-titrate exercise intensity

Magnet available
Special Patient Populations
Pacemaker

Standard 4 letter code:
– 1st letter – chamber paced A(atria), V(ventricle),
D(dual)
– 2nd Letter – chamber sensed A, V, D
– 3rd Letter – response to sensed event
– 4th Letter – rate-response capabilities of the
pacemaker

Examples: VVI, VVIR, AAI, DDDR
Special Patient Populations
Pacemaker & ICD
 Hx
resuscitated cardiac death, V.dysrhythmias,
disease of sinus node or conduction system
 PM
& ICD pts adapt to physical conditioning
similar to pts with CAD who are HR responsive
Special Patient Populations
Pacemaker & ICD

Intensity: 10% below activation. 10 bpm below
HR for activation of ICD

Activities that stretch the arms

Resume non-ballistic activities after 8 wks

Ballistic after 12 weeks

Pacemaker patients should not raise arms
above shoulders for 3 weeks
Special Patient Populations
Fixed Rate Pacemaker

Attenuated rise in cardiac output

Little to no chronotropic reserve, not linear to
VO2

Extend WU & CD

SBP monitoring throughout

Functional capacity may be impaired
Special Patient Populations
Cardiac Transplant

Marked exercise intolerance, believed to be d/t
lack of myocardial innervations

Med mgt focuses mainly on preventing rejection

Often have elevated rest HR & BP

Attenuated increase in HR with exercise

Lower peak HR, and delayed recovery
Special Patient Populations
Cardiac Transplant
 Prescription
guidelines:
–  WU & CD time, post HR remain high
– RPE 11-14 should be main intensity tool
– Avoid HR prescription for at least 1 yr
 Resistance
training
– Restrict upper-body until sternum is healed (6-12
weeks)
– 7-10 exercises, 2x/wk
Special Patient Populations
Cardiac Surgery
 CABG
and valve surgery
 Range
of Motion (ROM) in early days following
procedures to prevent adhesions, postural
problems
– Common chest & shoulder pathology
 Aerobic
intensity = 40/50%-85% HRR
 Resistance
training
– Restrict upper body movement until sternum is healed
(6-12 wks)
Special Patient Populations
PCI

Aerobic & RT can begin almost immediately

Ex rx similar to that for regular cardiac patients
& may progress more rapidly if minor myocardial
damage & less inactivity pre & post procedure

Groin check

Monitor S/S of restenosis

Should aim for 1500-2000 kCal of physical
activity each week
Metabolic Equations
ACSM certification review - Chapter 11
Guidelines - Chapter 7
Metabolic Calculations

Chapter 11 of ACSM certification review is the
most comprehensive resource for metabolic
calculations

See table 7.2 (ACSM guidelines) for formulas

Figure 7.2 (ACSM guidelines) shows application
of various methods for prescribing exercise
intensity
Metabolic equations
1. How many minutes per week would a 70 kg man
have to exercise to achieve a net caloric expenditure
of 2100 kcal if he exercise at 6 METs?
AEROBIC
1) 6 METs = 5METs net expenditure = 17.5 ml/kg/min
2) 17.5 ml/kg/min = 1225 ml/min = 1.225 L/min
3) 1.225L/min O2 = 6 kcal
4) 2100 kcal/6kcal/min = 350 minutes or 50 minutes/day
Metabolic Equations
2. What is the oxygen consumption equivalent to
10 METs for a 155lb male?
Conversions:
 10
METs = 35mL/kg/min
 155lb  1kg/2.2lb
= 70.45kg
35mL/kg/min75.45kg = 2456.75mL/min
2456.75mL/min  (1L/1000mL)= 2.47L/min
Metabolic Equations
3. What resistance (in Kp) should you set a
Monark cycle ergometer at to elicit a VO2 of
2750mL/min while cycling at 50 RPM? The
subject is 65” tall & weighs 110lb.

Conversions:
110lb  1kg/2.2lb = 50kg
2750mL/min/50kg = 55mL/kg/min
(50 rev/1min)  (6M/rev) = 300M/min
Metabolic Equations
3. What resistance (in Kp) should you set a
Monark cycle ergometer at to elicit a VO2 of
2750mL/min while cycling at 50 RPM? The
subject is 65” tall & weighs 110lb.
 55mL/kg/min
= ([1.8  F  300]/50kg) +
3.5mL/kg/min + 3.5mL/kg/min
Rearrange:
55ml/kg/min – 7mL/kg/min = 48 mL/kg/min
48mL/kg/min(50kg) = 4.4Kp
[1.8  300M/min])