What ST-segment change constitutes an absolute indication to stop a maximal exercise test?

What ST-segment change constitutes an absolute indication to stop a maximal exercise test?

• A. Any ST-segment change is acceptable to continue.
• B. ST-segment depression >1.0 mm in lateral leads.
• C. ST-segment elevation >1.0 mm in leads without pre-existing Q waves (other than aVR, aVL, or V1).
• D. T-wave inversion in inferior leads.

Answer: (C)

The main idea here is recognizing an ST-segment change during maximal exercise that cannot be ignored because it signals acute, potentially dangerous heart ischemia. A new ST-segment elevation of 1.0 mm or more in leads that do not have pre-existing Q waves (with the exceptions of certain leads like aVR, aVL, or V1) is considered an absolute reason to stop the test. This pattern points to transmural ischemia or injury occurring with the stress of exercise, and continuing could worsen myocardial damage, so stopping immediately is required. Why this is the best answer: new ST elevation in those leads is a direct, time-sensitive warning sign of acute ischemia or infarction during the test, demanding urgent attention and cessation of the exercise trial. The other patterns—such as ST-segment depression, T-wave inversion in a region—are important ischemic signs but do not carry the same universal, immediate directive to stop a maximal test. An ST change of any kind isn’t automatically cause to halt, and the specific context of elevation in the appropriate leads makes it the clear, safest stopping criterion.

The main idea here is recognizing an ST-segment change during maximal exercise that cannot be ignored because it signals acute, potentially dangerous heart ischemia. A new ST-segment elevation of 1.0 mm or more in leads that do not have pre-existing Q waves (with the exceptions of certain leads like aVR, aVL, or V1) is considered an absolute reason to stop the test. This pattern points to transmural ischemia or injury occurring with the stress of exercise, and continuing could worsen myocardial damage, so stopping immediately is required.

Why this is the best answer: new ST elevation in those leads is a direct, time-sensitive warning sign of acute ischemia or infarction during the test, demanding urgent attention and cessation of the exercise trial. The other patterns—such as ST-segment depression, T-wave inversion in a region—are important ischemic signs but do not carry the same universal, immediate directive to stop a maximal test. An ST change of any kind isn’t automatically cause to halt, and the specific context of elevation in the appropriate leads makes it the clear, safest stopping criterion.