Syndrome X

Can you give me any info on cardiac syndrome x?
I have been experiencing chest pain on the left along with arm, jaw and neck pain on that side. Several ecg, chest x ray, blood tests and one echo have not showed a problem so far. Its been blamed on costochondritis/anxiety and muscoskeltal issues.
I read about the above syndrome in a dr advice page of a magazine although it didn't give much info. Can it be possible this is causing my pain?
I am a 23yr old female

Thanks for your help

[Cleveland Clinic]

We don't use that term much and there is some misunderstanding as to its use, however, in a 23 year old female without diabetes or smoking it stands for coronary artery vasospasm.  There probably isn't coronary artery disease present (blockages), however, for some reason the coronary arteries may be very sensitive to certain chemicals or hormones in our body leading to coronary artery spasm which then may result in chest pain.  It is a difficult diagnosis to make, however, careful history and a trial of a medication called nitroglycerin may be helpful.  Very rarely, we have taken patients to the cath lab and performed ergonovine challenges to see whether or not this vasoreactive drug could reproduce these symptoms.  Syndrome X is a diagnosis of exclusion, however, therefore, all other potential cause of chest pain should be ruled out first.