Impossible question to answer, even by some of the best scientists in the world.
Equivicol stress test usually means that for whatever reason they can't make an accurate interpretation.
Most common causes of this are:
1. Having to stop the test early
2. Technical problems
In any case the doctor is likely to want to try another stress test using another method.. Such as a dobutamine (chemical) stress test, or a nuclear medicine study.
Most pre-op cases that turn up equivicol wind up getting approval from cardiology anyways, because its frankly debatable how effective stress testing a patient is at predicting surgical outcomes. Hence why i say its impossible to answer.
No surgery is truly "safe", at least thats my personal take on it anyways. Even if you had a perfect stress test i dont feel the data is strong enough for anyone to say that result alone does anything to predict mortality.