This document provides information on exercise physiology and exercise stress testing. It discusses: - How exercise increases cardiac oxygen demand through increased heart rate, contractility, and wall tension. - Metabolic equivalents (METs) as a measure of energy expenditure during physical activities. - Indications, contraindications, and safety of exercise stress testing. - Interpretation of electrocardiogram results during testing and factors that can cause false positives. - Definitions related to test accuracy and predictive values.

1. Or
HOW
NOT
TO Rest On
YOUR Laurels
OR
Your Hunchs!!!!
+ Life ON the treadmill

2. Exercise Physiology I
●- O2 Extraction Myocardial Cells
>70%
●- Myocardial metabolism
Virtually aerobic
●- Incr Cardiac O2 demand =>
Incr Coronary Flow
●- O2 demand ƒ HR, Inotropy,
Wall tension (LVpress * radius)

3. Exercise Physiology II
●- DoubleProduct (B/P * HR)
correlates O2 demand
●- ANGINA threshold = constant
DoubleProduct

4. + MET
●- Metabolic Equivalent = 3.5
ml/kg/min
●- One MET = energy expended
sitting quietly in a chair
●- 3-4 METS = walking @ 3mph &
Cycling at 6mph
●- 5-6 METS= walking @ 4mph &
Cycling at 10mph
●- 10-11 METS = running @ 6mph

5. + Types of Exercise
●- Static - isometric (e.g.,
handgrip)
●- Dynamic- rhythmic
contractions of extensor/flexor
grps
●- Combination of static/dynamic

6. + Why use dynamic exercise?
●- Isometric exaggerated BP
response
●- HR response is variable
●- Angina less reliably provoked
during isometric
●- Isometric exercise can provoke
V-arrhythmias
●- EKG changes during exercise
can be obscured

7. + Indications
●- Differential diagnosis of chest
pain
●- Assessment of functional level
of angina
●- Evaluation of therapy for
angina
●- Evaluation of functional
disability 2° OHD
●- Asymptomatic > 40 yr old with
multiple CRF’s

8. + Contraindications
●- Unstable Angina
●- Recent MI (no maximal test)
●- Rapid ventricular or atrial
arrythmias at rest
●- Advanced AV block (new
onset)
●- Uncompensated CHF
●- Acute noncardiac illness
●- Severe aortic stenosis
●- B/P > 170/100 prior to exercise

9. + Safety
●- Macondes 2 cases MI in 9000
TMT’s
●- Irving & Bruce 6 cases Arrest
in 10,000 TMT’s
●- Rochmis & Blackburn 170,000
Tmts (4/10,000 deaths)
●- Stuart & Ellestad 518,448
TMT’s 2 deaths & 9 MI’s per
10,000 TMT’s
●- Relative risk is 60-100x’s that
of ADL in pxts with CAD

10. + Terminate the Test - NOT the
Pxt I
●- Achieve predicted HR
●- Patient unable to continue
exercising (fatigue, claudication,
dyspnea)
●- PVC’s incr in freq or
ventricular tachycardia
●- Onset of advanced AV block

11. + Terminate the Test - NOT the
Pxt II
●- Severe angina
●- Diagnostic EKG’s changes
●- B/P criteria met : Sys > 220 or
Dias > 120 or B/P during
exercise < baseline
measurement
●- Exercise induced BBB
●- Failure of monitoring system

12. + POST test monitoring
●- Observe supine X 5 mins with
continous EKG monitoring
●- Continuous analysis of EKG
●- Return of EKG to baseline
prior to release of patient

13. + Interpretation I
●- ST segment changes are most reliable
EKG indicators of ischemia
●- Horizontal or downsloping response >
1mm below isoelectric at the J point
which persists > 80 msec is a positive
response
●- � 2mm criteria decreases false positive
rate; 3 consecutive beats without
variation are required to call positive
●- Depth of depression roughly correlative
with degree of ischemia

14. + Interpretation II
●- � 3mm depression or ST segment
changes Š 3 mins exercise or
persistence 9 mins into recovery = 3(or 2
vessel dz) 85% predictive value
●- Depression of J point with rapid rise in
ST segment normal response
●- Depression of J point with slow rising
ST segment and 2.0 mm ST depression at
80 msec from J point correlates with
CAD, however, false positive rate aprox
32%, so this is equivocal interpretation

15. + Interpretation III
●- ST segment elevation rare,
implies severe ischemia or LV
aneurysm
●- Eval workload performed
●- Eval HR and B/P response
●- Comment on presence of
arrhythmias
●- Comment on presence or
absence of symtoms

16. + Non atherosclerotic causes of
ST segment depression/False +
Test I
●- Supply/demand imbalance
(anemia, Aov stenosis,
coronary spasm, severe Htn,
LVH, HCM)
●- LBBB (repolarization
abnormalities unrelated to
supply/demand)
●- Drugs (Digoxin, antiHtn)

17. + Non atherosclerotic causes of
ST segment depression/False +
Test- II
●- Miscellanous
(Cardiomyopathies, MVP,
Syndrome X)
●- Hypokalemia, recent food
or glucose ingestion

18. + Definitions
●- Sensitivity = (TP/(TP + FN)
)*100
●- Specificity = (TN/(FP + TN)
)*100
●- Relative Risk = (TP/(TP + FN)) /
(FN/(TN+FN))
●- Predictive Value of Positive
Test= (TP/(TP+FP))*100

19. + Pre & Post Test Probablities
●- Diamond GA, Forrester JS: N.
Engl J Med 1979;300:1350-1358.,
duration 2-10 mins, relieved by
nitroglycerin
●- Atypical Angina- some but not
all
●- Nonanginal Chest pain- none
of the characteristics

20. + Predictive value of
conventional TMT -
Conventional View
●- Sensitivity 64%
●- Specificity 85%
●- Predictive value 80%
●- Dependent upon severity of
disease

21. + Accuracy of ST Segment
●- Exercise Electrocardiogram
Meta-Analysis, Prog CV
Diseases, Nov/Dec 1989
●- Sensitivity 68%
●- Specificity 77%
●- Mean sensitivity for L-main
and 3 vessel disease 86%

22. + ‘Markedly Postive’ criteria
●- Downsloping
●- > 2mm ST segment depression
●- Begining at less than 5 METs
activity
●- Persisting longer than 6 mins
into recovery
●- Involving at least 5 EKG leads

23. + Predictibility of “Markedly
positive criteria to Diagnosis
L-main Dz
●- Predictive value 32%
●- Sensitivity 74%
●- Weiner et al 436 pxts/35 with
LM dz

24. + Predictibility of B/P criteria to
predict angiographic disease
●- 3VD sensitivity 15%,
Specificity 92%, Predictive value
45%
●- LM sensitivity 15%, Specificity
93%, Predictive value 16%
●- EF < 30% 12%, Specificity 92%,
Predictive value 6%
●- Seattle HeartWatch study

25. + Depressed Downsloping ST
segments
●- Within 3 mins of exercise
●- Persisting > 8 mins into
recovery
●- 90% had L-main or 2V/3V CAD
●- Goldschlager et al

26. + Positive Response in Bruce I
or II
●- McNeer et al
●- 97% had significant CAD

27. THE END