A little education on cardiopulmonary exercise testing

Based on the " Cardiopulmonary Exercise Test - Patient Education Content " released by the American Cardiothoracic Association, the editor will further introduce the content of this clinical test, the applicable population, and the main results to help you answer three questions: Why do you need to do this test? Is it appropriate to do this test? And what can I get from this test?

Cardiopulmonary exercise testing (CPET) , also known as a VO2 (oxygen consumption) test, is a stress test designed to measure exercise capacity. The test gathers information about heart and lung breathing to determine whether the body is responding normally to exercise.

Why should I take this test? Reasons for the general population to take this test include:

Assessing athletic ability

Determining the cause of unexplained shortness of breath

Before surgery, this test can be used to assess surgical risks

For patients with known heart or lung disease, CPET can:

Check for severity of respiratory disease (eg, chronic obstructive pulmonary disease, pulmonary vascular disease, cystic fibrosis, etc.)

For people who have both heart and lung disorders, to determine how much of the limited exercise is due to the heart disorder or the lung disorder

Determine the extent of a patient's activity limitation or impairment to guide the amount of rehabilitation training and develop an exercise prescription

To evaluate whether exercise capacity improves significantly after heart transplantation in patients with congestive heart failure.

In what cases is CPET not suitable for me? Generally, it includes:

Musculoskeletal problems that prevent you from walking or running on a treadmill or cycling on a stationary bicycle

Suffering from acute illness or chronic illness that is difficult to treat with medication

Recent myocardial infarction (an absolute contraindication if it occurs within two days)

Severe hypoxia

Severe hypertension

Uncontrolled or abnormal heart rate

Note: Also tell your doctor about any recent changes in your health, such as acute infections or injuries that limit your activities.

How does the test take place? What can I expect from it? The test begins with lung function testing, including spirometry, as well as additional tests.

First, prepare for the exercise part of the test. The staff will put on you the equipment to monitor your heart function and lung breathing, including ECG monitoring equipment, blood oximeter, blood pressure cuff, breathing mask, etc., to monitor the changes in ECG, blood oxygen saturation, and blood pressure response to exercise in real time during exercise.

According to the test objectives, your exercise habits, and possible musculoskeletal problems, the tester will choose a stationary bike or running test that is suitable for you. The test is divided into four stages. The first three minutes are the rest stage. The tester will tell you the next process and remind you not to talk during the test to avoid affecting the test results. Next is the warm-up stage, walking on the treadmill or riding freely on the bicycle (riding without resistance) for about three minutes. Then enter the test stage. According to the test plan, when the slope increases, you can walk or run on the treadmill at a faster speed; on the bicycle, the resistance to pedaling will gradually increase, but you still have to keep riding at a certain speed. The purpose of the test is to gradually increase the speed or resistance, increase the difficulty until you can no longer continue the activity, and reach the maximum amount of exercise. The entire test lasts 8-12 minutes. During this exercise, you must do your best to stick to it so as to understand what is limiting your exercise ability.

During the test, the tester will encourage or remind you what to do. When you are too tired to continue, the test ends, but you will continue to walk slowly or ride a bicycle without resistance for three minutes to enter the relaxation stage, thereby slowly reducing the heart pumping blood and preventing adverse events. After the exercise, you may still need a short period of monitoring to ensure that the data is stable before you can leave. The tester will issue an exercise report based on your exercise performance to help you understand your exercise endurance, and the doctor will formulate a suitable daily exercise prescription for you based on the results to help you improve your cardiopulmonary endurance and exercise ability.

The popular science content of this platform has been funded by the China Association for Science and Technology's Science Popularization Department's 2022 National Science Literacy Action Project "National Society Science Popularization Capacity Improvement Project-Rehabilitation Science Popularization Service Capacity Improvement Action Plan"