Why Cardiopulmonary Exercise Testing?

Cardiovascular disease is one of the two leading causes of death for men and women according to Statistics Canada.

The primary goal of preventive medicine is to avoid the manifestation of disease. Since many disease processes take time to develop, it is possible to detect their evolution at an earlier stage before they present a health burden.

Disease of an organ system reduces its capacity to function. Most organ systems have a large functional reserve; therefore clinical manifestation may only occur when the organ system's capacity is greatly reduced. This occurs during advanced disease or when the system's demands are greatly increased.

Stressing the organ systems, or pushing the physiological processes to function at a level near their limit, may reveal disturbances or abnormalities present in the systems. Thus earlier detection and intervention can be achieved by examination under increased demand, as with stress testing.

Exercise demands the interplay of the whole organism. The best known example of the application of these principles is in the exercise stress test for heart disease (exercise ECG). At rest the electrocardiogram may be normal, but during the exercise as the demands for oxygen and increased blood flow to the heart grow, deficiencies in the system may become apparent. Narrowed arteries which deliver sufficient blood to the heart at rest now cannot carry the amounts required by the increased demand and abnormalities may appear on the electrocardiogram. In effect, this test uses one measure to assess the end result of a complex process.

While there are controversies as to the sensitivity and specificity of the exercise ECG, it remains a very practical and useful tool for the cardiologist. But if we relate only to one link in the chain as in looking only at the electrocardiograms, we may miss other important factors. Cardiopulmonary exercise testing, as used by HEALTH AUDIT significantly widens the scope of systems and areas that can be assessed using much the same principles.(34) It is clear that if several different parameters are examined and their interaction interpreted, a wide range of pathological and physiological processes can be evaluated. Using these techniques, the physiological functions can be assessed to give both a picture of the overall performance abilities of the individual, as well as to identify those systems which show signs of malfunction.

In exercise, the body systems – respiratory, cardiovascular and muscular function in concert. This is shown by the following cogwheel diagram. Each system can be seen to be linked in a dynamic chain. The strength of the whole system is determined by its weakest link.

Cardiopulmonary exercise testing as used in HEALTH AUDIT is concerned with measuring the individual components of the system. By applying the necessary knowledge, experience and data base comparisons to the responses during a cardiopulmonary exercise test; we can identify the weak link in the chain and offer specific interventions to improve the deficiency. In addition to its diagnostic value, the cardiopulmonary exercise test establishes a quantitative basis for prescribing; type, duration, intensity and frequency of exercise in a program.

  1. Inbar O., D. Elian, T. Bar-Razon, R. Dlin, E. Klainman. Cardiopulmonary responses during exercise improves the diagnostic accuracy of stress testing. Adv. Exerc. Sports Physiol., Vol. 11 No. 1 pp. 1-8, 2005

  2. Belardineli, R., Lacalaprice, F., Carle, F., et.al. Exercise-induced myocardial ischaemia detected by cardiopulmonary exercise testing. European Heart Journal (2003) pp.1304-1313.