What's provocable ischemia?

Stress test. Stress tests with exercise or drugs are used to provoke ischemia, to uncover insufficient blood flow to the heart muscle.
Arterial blockage. Ischemia infers that the arteries that feed these parts of the heart are narrowed such that blood flow through them reduces with exertion. It means these areas of the heart are vulnerable and further testing is needed and intervention may be necessary. Provokable means that it's evident with exertion but not at rest.