S1: Cardiopulmonary exercise testing

Question 1

What does CPET stand for?

Answer 1

Cardiopulmonary Exercise Testing

Question 2

What physiological parameters are measured during CPET?

Answer 2

VO2, VCO2, oxygen saturation, ventilation, and heart rate

Question 3

What is VO2max?

Answer 3

The maximal rate of oxygen consumption during exercise

Question 4

What formula is used to calculate VO2?

Answer 4

VO2 = (SV x HR) x (CaO2 - CvO2)

Question 5

What is the significance of anaerobic threshold in CPET?

Answer 5

It indicates the point where lactate accumulation begins

Question 6

What does a low anaerobic threshold suggest?

Answer 6

Poor oxygen delivery, often due to cardiovascular or pulmonary limitations

Question 7

What is the respiratory exchange ratio (RER)?

Answer 7

The ratio of VCO2 to VO2

Question 8

What is the ‘nine-panel plot’ in CPET?

Answer 8

A graphical representation of key CPET parameters

Question 9

What does an increased VE/VCO2 slope indicate?

Answer 9

Reduced ventilatory efficiency or hyperventilation

Question 10

How is maximum ventilation predicted during CPET?

Answer 10

(FEV1 x 20) + 20

Question 11

What is oxygen pulse?

Answer 11

VO2 divided by heart rate, an indirect measure of stroke volume

Question 12

What is a normal maximum heart rate during CPET?

Answer 12

220 minus age

Question 13

What does a low heart rate reserve suggest in CPET?

Answer 13

Non-cardiovascular limitation to exercise

Question 14

How can CPET help predict surgical outcomes?

Answer 14

By assessing anaerobic threshold and overall fitness

Question 15

What is the ventilatory compensation point?

Answer 15

The point where ventilation increases disproportionately to CO2 production

Question 16

How does CPET differentiate causes of breathlessness?

Answer 16

By analyzing patterns of VO2, VCO2, and ventilation

Question 17

What is the normal VO2 at rest?

Answer 17

Approximately 250 ml/min

Question 18

How does body habitus affect VO2max?

Answer 18

Larger body size often increases absolute VO2max

Question 19

Why is VO2max a key indicator of cardiorespiratory fitness?

Answer 19

It correlates with endurance and mortality risk

Question 20

What is the significance of the A-a gradient in CPET?

Answer 20

It helps identify oxygenation issues during exercise

Question 21

How does hyperventilation appear in a VE/VCO2 slope?

Answer 21

As an increased slope, often due to acidosis or anxiety

Question 22

What does a reduced VE/VO2 ratio indicate?

Answer 22

Improved ventilatory efficiency

Question 23

What is the relationship between cardiac output and VO2?

Answer 23

Cardiac output is a primary determinant of VO2

Question 24

What did Myers et al.’s study conclude about exercise capacity?

Answer 24

It is a powerful predictor of mortality

Question 25

What is the predicted VO2max formula?

Answer 25

VO2max (ml/kg/min) ≈ 50 - (0.4 x age in years)

Question 26

Why are ventilatory equivalents important in CPET?

Answer 26

They measure the efficiency of ventilation in clearing CO2 and taking in O2

Question 27

How is stroke volume estimated during CPET?

Answer 27

Using oxygen pulse (VO2/HR)

Question 28

What is a hallmark of ventilatory limitation during CPET?

Answer 28

Maximum ventilation approaching predicted levels

Question 29

What is the clinical utility of CPET in heart failure?

Answer 29

Assessing functional capacity and prognosis

Question 30

What is the significance of the anaerobic threshold for surgery?

Answer 30

Lower thresholds are associated with higher surgical risk

Question 31

What parameters are analyzed to assess ventilatory efficiency?

Answer 31

VE/VCO2 and VE/VO2 ratios

Question 32

How is heart rate recovery analyzed in CPET?

Answer 32

By assessing the rate of HR decline post-exercise

Question 33

What is the impact of beta blockers on CPET results?

Answer 33

They may affect heart rate response and exercise capacity

Question 34

What does CPET reveal about pulmonary vascular disease?

Answer 34

Desaturation during exercise indicates potential vascular issues

Question 35

What role does CPET play in managing unexplained breathlessness?

Answer 35

Identifies potential cardiorespiratory limitations

Question 36

What is the VO2 plateau, and why is it important?

Answer 36

The point where oxygen uptake no longer increases with workload

Question 37

How does exercise training modify surgical risk?

Answer 37

By improving anaerobic threshold and cardiorespiratory fitness

Question 38

What is the relevance of VE/VCO2 slope in heart failure prognosis?

Answer 38

Higher slopes indicate worse outcomes

Question 39

How does CPET contribute to evaluating fitness for surgery?

Answer 39

By identifying cardiorespiratory reserves and limitations

Question 40

What is the link between CPET findings and mortality?

Answer 40

Markers of low fitness, like low VO2max, correlate with higher risk