My understanding is that it will only discover significant blockages (80-95%). It's cheap, though.
I had one long ago as a part of a scheduled physical. Frankly, it was too easy, and the doc kept admonishing me to keep my mouth shut and stop talking while doing the test. He finally stopped the test and announced "There is nothing wrong with you." It was useful to discover a major blockage in my sister in law, though ... so there is that.
Personally, I recommend a CT angiogram with contrast to check out the state of your coronary arteries. There are usually Groupons available to get that done for a couple hundred dollars, and it is well worth the peace of mind or the information. Discuss it with your doc.
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