TMT is exercise ECG and observation of patient during a graded stress. In males in the ages 30 and above with a normal ECG it gives a good information about the exercise tolerance and ECG changes during the exercise which increases the product of heart rate and blood pressure. This product called the double product increases the oxygen demand of heart.
If the ECG remains normal at peak exercise and at the predicted maximal heart rate for the age the chance of having a significant block in a major coronary artery is very low. The predictive value of the test increases if the person doing TMT remains asymptomatic and has a normal BP response and clinical examination immediately after exercise remains normal. A positive TMT has to be interpreted along with the total clinical picture and other risk factors (like diabetes, high lipids, family history, obesity, smoking etc).