What happens if there is ≥ 1 mm ST-segment depression during exercise?

Experiencing ≥ 1 mm of ST-segment depression during exercise is an important physiological indicator that can suggest myocardial ischemia or inadequate blood flow to the heart muscle. This response typically signals that the heart is under stress, and there may be a risk of more serious cardiac issues if exercise continues at the same intensity. As such, the recommendation to limit the intensity is based on the need to protect the individual from potential cardiovascular complications, such as angina or even a heart attack.

Monitoring the ST-segment during an exercise stress test is crucial, as changes can reflect how well the heart is coping with increased physical demands. If there are significant changes, as indicated by ST-segment depression, it is generally advisable to alter the exercise program. Therefore, modifying the intensity is a prudent step to ensure safety and health during physical activity.