The cardiopulmonary exercise test (CPET) is a highly sensitive, non-invasive stress test. A CPET assesses how well the heart, lungs, and muscles are working individually, and how these systems are working in unison.

The full cardiopulmonary system is assessed during a CPET by measuring the metabolic rate, the amount of oxygen your body is using (VO2 max), the amount of carbon dioxide it is producing, your breathing pattern and electrocardiogram while you are exercising.

CPET is useful in the following situations:

1. Evaluation of exercise capacity and response to treatment in patients with heart failure who are being considered for heart transplantation
2. Assessment for ischaemic heart disease
3. Assistance in the differentiation of heart versus lung limitations versus poor fitness as a cause of breathlessness.
4. Optimising the training intensity or training zones for athletes to improve their sporting performance