Exercise Treadmill Test (ETT)
An exercise treadmill test (ETT) provides the cardiologist with general information about how well the heart copes with exercise and may detect an underlying problem that is not present on the resting ECG. As the body works harder during exercise, the working muscles require more oxygen, so the heart must pump more blood. The test can show if there is a reduction in blood supply to the heart or if any abnormal heart rhythms develop with exercise.
During an exercise test, the ECG electrodes are attached to the patient and the readings constantly displayed on the treadmill monitor. The blood pressure is also recorded every 2-3 minutes. The treadmill starts slowly and the speed and its slope are increased every three minutes according to a standard protocol. The exercise treadmill test (ETT) is stopped when the patient achieves a target heart rate or if the patient develops symptoms, such as chest discomfort, breathlessness or dizziness. The test may also be stopped if there are significant changes on the ECG or blood pressure falls significantly (this should normally increase with exercise).