Cardiopulmonary exercise stress testing (CPEST) measures the body’s ability to perform gas exchange (oxygen consumed vs. carbon dioxide produced) during an ECG stress test. By measuring the performance of the respiratory, cardiovascular, and circulatory systems all in one test, the CPEST test gives the most complete global indicator of functional capacity. This testing detects the causes of symptoms such as shortness of breath, chest pain, and fatigue. It is, therefore, valuable in a wide variety of applications and is a practical tool for diagnosis and evaluation of therapy.
Uses of CPEST testing
- To quantitate exercise capacity
- To evaluate unexplained shortness of breath
- To determine the factors which limit activity (cardiac vs. pulmonary)
- To determine the extent of impairment in disability evaluations
- To formulate exercise prescriptions to safely maximize reconditioning
- To evaluate the effectiveness of rehabilitation
- To follow response to therapy in patient with cardiopulmonary disease
- To risk-stratify patients for major surgery.
Cardiologists use CPEST to detect and quantify heart failure, CAD, valvular heart disease and arrhythmias. The test is also used to differentiate diagnosis between pulmonary or cardiac limitations, follow up on interventions such as rehabilitation, drugs, pacing and assessment of post MI and heart failure.
Pulmonologist use of the test helps to evaluate patients with; COPD, IPF, pulmonary vascular disease along with; determining response to treatment such as oxygen, bronchodilators, pulmonary vasodilators, dietary changes and evaluation of disability.
CPEST is also used in patients being considered for heart transplantation, lung volume reduction, as well as post operation to quantify improvement and risk stratification of elderly patients scheduled for major surgery.
How it is done
An abbreviated PFT will be completed. Baseline measurements of heart rate, blood pressure, oxygen saturation, and electrocardiogram are then obtained. The patient will mount either a bicycle or treadmill and will have a nose clip and a mouth piece used to measure oxygen consumption on their nose and in their mouth respectively.
How it feels
This is a diagnostic activity which requires maximal effort. It is not unusual to feel tired or fatigued when the test is completed.
Cardiopulmonary testing presents little or no risk in the healthy individual. However, those that present for testing with serious lung or cardiac conditions a written order must be presented to the lab before testing can take place. In that event, there is a physician present to oversee the testing in case a problem should arise.
What affects the test?
There are reasons why test results might not be helpful which include; poor effort, use of beta blockers for those with cardiac problems, heart, peripheral vascular, lung, endocrine and/or musculoskeletal diseases.