What are the precautions for undergoing a treadmill test (TMT)? Cardiology Basics

What are the precautions for undergoing a treadmill test (TMT)? Cardiology Basics

Treadmill exercise test is often taken as a fitness test during routine medical check-up. TMT is also done for evaluation of a case of suspected coronary artery disease and as part of post myocardial infarction evaluation. TMT in children is often for the evaluation of arrhythmic disorders. But this is not a test meant for everyone coming for a health check-up. A preliminary assessment of the fitness of an individual to undergo a treadmill test (TMT) is desirable.

This will include a short check on whether the person has any medical conditions which could increase the risk of the test. Moreover, it is difficult for persons with physical disabilities to undergo the test.

Anyone who has had a recent episode of chest pain, dizziness or breathlessness needs a full evaluation of cardiac status prior to TMT. This might include an echocardiogram to exclude structural heart disease and for assessment of left ventricular function.

If there is no such instance and one has a reasonable effort tolerance in the form of ability to climb two flights of stairs at stretch during routine activities, it is reasonable to undergo a treadmill test without a full cardiac evaluation.

Older persons seeking to start an exercise program for fitness needs to undergo TMT in the hospital prior to initiation of such programs as some of them may have silent coronary artery disease. Silent ischemia can become manifest in such individuals during unaccustomed exertion. This could also precipitate a cardiovascular event like acute myocardial infarction or acute left ventricular failure.

An initial recording of the ECG is done by the technician before the TMT. If an old ECG is available, the current one is compared with the old one for any fresh changes. If fresh changes are detected, the test is deferred, and further testing sought.

Initial blood pressure, heart rate, height and weight are recorded prior to the test. If there is an extreme of heart rate or blood pressure, again a medical evaluation is sought. Anyone with a current illness like fever is not taken up for treadmill test.

Those with disabilities of lower limb naturally find it difficult to do a treadmill test. Upper limb disability, though it may cause some discomfort in holding balance during treadmill, need not necessitate deferral of the test. They a need a little more motivation during the test for completion of the test and possibly a longer duration of initial test run for familiarizing treadmill walking.

The person undergoing treadmill test is advised to report immediately if there is any chest discomfort, giddiness, breathlessness or any other new symptom. The technician and doctor in the treadmill room continuously monitors the heart rate and ECG changes during treadmill test to ensure safety.
Any significant change in the ECG, heart rhythm or symptoms mandate immediate termination of the test and further observation.

Treadmill room is equipped with all emergency care equipment including a defibrillator and resuscitation tray to deal with any untoward event during TMT.

Observation for a short period after the test is also routine, to detect any changes in the ECG during recovery period, which is not uncommon. Those developing persistent ECG changes or fresh symptoms may be advised hospital admission and further care.