2. Pathophysiology
• At rest- adequate coronary blood flow
• with exercise-supplydemand mismatch -ST segment
changes
• 70-80%occlusion - detection by EST
• Sign CAD can exist with a -VE Exercise Stress Test.
4. The Bruce protocol
• 1949 by Robert A. Bruce, con
sidered the “father of exercise
physiology”.
• Published as a standardized pr
otocol in 1963.
• gold-standard for detection o
f myocardial ischemia when ri
sk stratification is necessary.
6. Peak Vo2 is the same regardless of the protocol used
diff – rate at which it is achieved
PROTOCOL USES COMMENTS
BRUCE Normally used large↑Vo2 bet stagesr
unning≥st 3
NAUGHTON&WEBER Limited ex tolerance-CCF 1-2 min stages1 MET in
crement
ACIP Established CAD 2 min stages> linear ↑ i
n HR & Vo2
MOD-ACIP Short elderly individuals
7. Procedure
• Standard 12 lead ECG- leads
• Torso ECG + BP
• Supine and Sitting / standing
• HR ,BP ,ECG
• Before,after,stage
• Onset of ischemic response
• Each min recovery(5-10 mints)
8. Procedure- Lead systems
• Mason-Liker modification-extremity electrodes move
d to torso 2 ↓ motion artifacts
• RAD
• ↑inf lead voltage
• Loss of inf lead q
• New Q in AVL
9. Contraindications to Exercise Testing
Absolute
• A/c MI (< 2 d)
• High-risk unstable angina
• Uncontrolled cardiac arrhythmias causing sympto
ms or hemo compromise
• Symptomatic severe AS
• Uncontrolled symptomatic CCF
• Acute pulmonary embolus or pulmonary infarcti
on
• A/c myocarditis or pericarditis
• A/c Ao dissection
10. Contraindications to Exercise Testing
Relative
• LMCA stenosis
• Mod- stenotic VHD
• Electrolyte abnormalities
• Sev HTN
• Tachyarrhythmias or bradyarrhythmias
• HOCM and other outflow tract obstructions
• Mental or physical impairment leading to inabili
ty to exercise adequately
• High-degree AV block
11. SAFETY & RISKS
In nonselected pat pop-mortality- .01%
-morbidity-.05%
In k/c CAD- 1 C.arrest/59000 person hours
-AMI in 1.4 / 10000 tests
Arrythmias-AF-Mc-9/10,000 tests
-VT-6/10,000 tests
-VF- .6/10,000 tests
Deaths& MI estimated occur in 1 of 25000 tests
12. The post test probability is proportional to
the pretest probability
To diagnose, test sensitivity ,specificity&
prevalence in the population being tested
req
Bayes' theorem
A theory of probability
13. • Sensitivity- a person with the disease having a posit
ive test.
• Specificity-person without the disease having a neg
ative test.
• Prevalence- % in the population having disease.
14. Pretest Probability
• Based on the pat's h/o ( age, gender, chest pain ), phy ex a
nd initial testing, and the clinician's experience.
• Typical or definite angina →pretest probability high - test r
esult does not dramatically change the probability.
• Diag power maximal when the pretest probability is inter
mediate-30-70%
15. Classification of chest pain
• Typical angina
1. Substernal chest discomfort with characterstic quality and
duration
2. Provoked by exertion or emotional stress
3. Relieved by rest or NTG
• Atypical angina
• Meets 2 of the above characteristics
• Noncardiac chest pain
• Meets one or none of the typical characteristics
16. Pre Test Probability of Coronary Disease by Symptoms,
Gender and Age
Age Gender Typical/Definite
Angina Pectoris
Atypical/Probable
Angina Pectoris
Non-
Anginal
Chest Pain
Asymptomatic
30-39 Males Intermediate Intermediate low (<10%) Very low (<5%)
30-39 Females Intermediate Very Low (<5%) Very low Very low
40-49 Males High (>90%) Intermediate Intermediate low
40-49 Females Intermediate Low Very low Very low
50-59 Males High (>90%) Intermediate Intermediate Low
50-59 Females Intermediate Intermediate Low Very low
60-69 Males High Intermediate Intermediate Low
60-69 Females High Intermediate Intermediate Low
High = >90% Intermediate = 10-90% Low = <10%
Very Low = <5%
17. INTERMEDIATE CATEGORY
AGE GROUP GENDER & SYMPTOMS
30-39 YEARS M& F + TYPICAL ANGINA
M + ATYPICAL/ PROBABLE ANGINA
40-49 YEARS F + TYPICAL ANGINA
M + ATYPICAL/ NON ANGINAL CP
50-59 YEARS F+ TYPICAL ANGINA
M&F + ATYPICAL NAGINA
M+ NON ACP
60-69 YEARS M& F+ ATYPICAL/PROB ANGINA
M&F + NACP
18. E T TO DIAGNOSE OBSTRUCTIVE CAD
Class I
• Adult (including RBBB or <1 mm of resting ST↓) with
intermed pretest probability of CAD
Class IIa
• Patients with vasospastic angina.
19. E T TO DIAGNOSE OBSTRUCTIVE CAD
Class IIb
1. Patients - high pretest probability of CAD
2. Patients - low pretest probability of CAD
3. Patients with <1 mm of baseline ST ↓and on digoxin.
4. Patients with LVH and <1 mm baseline ST ↓.
Class III
1. Patients with the following baseline ECG abnormalities
:
• Pre-excitation syndrome
• Electronically paced ventricular rhythm
• >1 mm of resting ST depression
• Complete LBBB
21. Exercise Testing in Asymptomatic Persons
Without Known CAD
Class I
• None.
Class IIa
• Evaluation of asymP DM pts - plan to start vigorous exercise ( C)
Class IIb
• 1. Eval of pts with multiple risk factors - guide to risk-reduction therapy.
• 2. Eval of asymptomatic men > 45 yrs and women >55 yrs:
Plan to start vigorous exercise
Involved in occupations which impact public safety
High risk for CAD(e.g., PVOD and CRF)
Class III
• Routine screening of asymptomatic
22. RISK ASSESS AND PROG IN PAT WITH SYMP OR A PRIOR HISTOR
Y OF CAD
Class I
1. Initial evalu with susp/known CAD +/- RBBB or <1
mm of resting ST Depression
2.Susp/ known CAD, previously evaluated-+ signi ch
ange in clinical status nw
3. Low-risk UA pts >8 to 12 hrs & free of active isch
emia/CCF
4. Intermed-risk UApts > 2 to 3 days & no active isc
hemia/ CCF
Class IIa
Intermed-risk UA pts – initial markers (N),rpt ECG –n
o signi change, and markers >6-12 hrs (N) & no oth
er evidence of ischemia during observation.
