CPET, or cardiopulmonary exercise testing, is the gold standard for assessing functional capacity in heart failure patients. It combines ECG stress testing with measurements of gas exchange and ventilation. Key parameters measured include oxygen uptake, carbon dioxide production, minute ventilation, heart rate, and oxygen saturation. CPET can help determine if exercise limitation is due to pulmonary, cardiovascular, or peripheral causes by measuring values like oxygen pulse and the ventilatory threshold. It has several clinical applications for evaluating unexplained dyspnea, monitoring disease progression, and preoperative risk assessment.

1. CPET .…..
The Gold
Standrad
AHMED KADRY,MD
LECTURER OF CARDIOLOGY
AIN SHAMS UNIVERSITY

2. we use Echocardiography to assess functional
capacity in heart failure patients???

3. we use Echocardiography to assess functional
capacity in heart failure patients???

4. Echocardiography is “the single most
useful test in the diagnosis &
classification of patients with HF, yet it
gives little information about functional
capacity”

5. Functional capacity is best assessed with
Cardiopulmonary exercise (CPET) testing
“Gold standard”

6. OUTLINE
• CPET and its terminology
• Exercise physiology
• Interpretation of CPET results
• Indications in clinical practice

7. OUTLINE
•CPET and its terminology
• Exercise physiology
• Interpretation of CPET results
• Indications in clinical practice

8. CPET
Symptom-limited provocative test
Combines
1.ECG stress testing
2.Indices of gas exchange and spirometry

9. KEY PARAMETERS
• Oxygen uptake
• Carbon dioxide production
• Minute ventilation( VE=VT *RR)
• Heart rate
• Oxygen saturation

10. KEY DEFINITIONS
• Oxygen uptake
• Carbon dioxide production
• Minute ventilation
• Heart rate
• Oxygen saturation
Ventilatory
equivalents for
O2
(VO2)

11. Oxygen consumption during exercise(VO2)
• VO2 is the amount of O2 utilized by tissues per minute
• Peak VO2 is the amount of oxygen utilized by tissues at peak exercise.
• Absolute ml/min
• Relative ml/mim/kg
Reference:
• Resting VO2  3.5 ml/kg/min (250 ML/MIN)
• Peak VO2  > 84% of predicted or >25 ml/kg/min (30-50 ml/kg/min)

12. KEY DEFINITIONS
• Oxygen uptake
• Carbon dioxide production
• Minute ventilation
• Heart rate
• Oxygen saturation
Hyperventilation if assosciated with decreased Etco2
Increased VD/VT if associated with increased Etco2
Ventilatory
equivalents for CO2
(Vco2)
N < 34

13. KEY DEFINITIONS
• Oxygen uptake
• Carbon dioxide production
• Minute ventilation
• Heart rate
• Oxygen saturation
Respiratory
exchange ratio
(RER)

14. Respiratory Exchange Ratio(RER)
• Used to determine adequacy of effort
• The threshold you can say that this test is adequate regardless
target heart rate
• RER= VCO2 / VO2
• RER occur near 1
• Values > 1.1 = adequate effort

15. KEY DEFINITIONS
• Oxygen uptake
• Carbon dioxide production
• Minute ventilation
• Heart rate
• Oxygen saturation
Oxygen pulse
VO2/HR

16. Oxygen Pulse
• Volume of oxygen consumed per heart beat
• Surrogate to evaluate stroke volume
• Vo2/HR = SV(CaO2-Cvo2)
Normal
• > 80% of predicted(predicted vo2 max/ predicted max HR)
• 15 ml/b in men 10 ml/b in women

17. OUTLINE
• CPET and its terminology
•Exercise physiology
• Interpretation of CPET results
• Indications in clinical practice

18. EXERCISE PHYSIOLOGY
Fick`s principle 
explains all aspects of exercise physiology
VO2=(CO*(CaO2- CvO2)

20. Anaerobic Threshold(AT)
• THE point of exercise at which the level of VCO2 increases
exponentially relative to VO2
• Normal is 55% of predicted peak VO2

22. What Limits A Normal Person
VO2=CO*(CaO2- CvO2)
• COP =(SV*HR)
• Is limited by reaching maximal heart rate
• Even at this point 25-30% ventilatory reserve is
present

23. Cardiovascular response to exercise
• COP increase linearly with VO2
• Initial increase caused by increase of SV and HR then HR
exclusively
• HR max =220 –age ( normal to achieve > 90%)
• HRR= age predicted HR max – HR max achived ( normal < 15
bpm)

24. ABP response to exercise
• SVR decrease
• Systolic ABP increase with normal diastolic ABP.
• Failure of SBP to increase indicates
1. Cardiac limitation
2. Sympathetic dysfunction

25. VENTILATORY RESERVE
• Potential ventilation in L that could be increased during exercise.
• VE=VT*RR
• Difference / ratio between VE max and MVV
• VEmax / MVV * 100 >75%
• Vemax – MVV >11L
• MVV (ventilatory mechanical limit)=FEV1*40
LUNG DISEASE REDUCED VENTILATORY RESERVE.
HEART DISEASE NORMAL VENTILATORY RESERVE.

29. MECHANISMS OF EXERCISE LIMITATION
Pulmonary
• Ventilatory
• Respiratory muscle dysfunction
• Impaired gas exchange
Deconditioning
Peripheral
 Neuromuscular dysfunction
 Metabolic dysfunction
Cardiovascular
 Reduced stroke volume
 Abnormal heart rate response
 Circulatory abnormality

36. When VO2 is decreased
( N >84% ,>25 ml/kg/min)
1. HR reach max limit??
2. RER>1.15??
3. Decrease in Etco2??
4. VE > 75% OF PREDICTED ???
5. Saturation decrease by 5% or more ???

37. When VO2 is decreased
( N >84% ,>25 ml/kg/min)
1. HR reach max limit??
2. RER>1.15??
3. Decrease in Etco2??
4. VE > 75% OF PREDICTED ???
5. Saturation decrease by 5% or more ???
cardiac

38. When VO2 is decreased
( N >84% ,>25 ml/kg/min)
1. HR reach max limit??
2. RER>1.15??
3. Decrease in Etco2??
4. VE > 75% OF PREDICTED ???
5. Saturation decrease by 5% or more ???
ventilatory

39. When VO2 is decreased
( N >84% ,>25 ml/kg/min)
1. HR reach max limit??
2. RER>1.15??
3. Decrease in Etco2??
4. VE > 75% OF PREDICTED ???
5. Saturation decrease by 5% or more ???

40. INDICATIONS OF CPET IN CLINICAL PRACTISE
•Unexplained
dyspnea
•Response to
intervention
Monitoring
disease
Preoperative risk
assessment