Hello, Thank you for your question
I will try my best to assist you with your queries.
One thing is for sure...three stress tests negative means less than 0.5% chance of having a possible atherosclerotic coronary artery disease.
There is a similar problem called vasospastic angina which can be considered as a possible cause. Your doctor should prescribe nitrates. If these help then there are very high chances that this is vasospastic angina. In presence of three negative stress test no one will do angiogram so we have to rely on this clinic pointer that nitrates helping your pain makes this type of angina more likely.
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