Welcome and thanks for your question I am Dr. German I would be here to help you and give you all the assistance you need until you are satisfied, if they already ruled out a breast issue ,it is important for you to contact other doctor to rule out and investigate other possibilities including:
1-Heart angina( in this condition, the heart blood flow becomes suddenly interrupted by the presence of a clot or sudden heart blood vessel vasoconstriction) or heart arrhythmia .
2-Costochondritis( in this condition, the cartilage that joins the breastbone to the upper ribs become swollen or inflamed).
4-Other possibility would be be gastrointestinal issues like: gastritis ,stomach ulcers, esophageal spasms( in which the esophagus muscles suddenly contract), gastroesophageal reflux( in this condition, the stomach acid juices flow back into the esophagus) or gallstones.
5- Emotional issues like depression or anxiety or back problems( like lower back bones inflammation, slipped upper back intervertebral disc and upper back nerve root compression) could also produce this type of symptoms you have been experiencing.
Your doctor will need to perform some tests including: a upper back X-rays, CT Scan or MRI, exercise stress test, an EKG, heart enzyme blood levels and an abdominal X-rays.
With these tests and a complete physical examination, Your doctor will be able to determine which of these conditions is affecting you so you can receive an appropriate treatment.
If you need any additional information I will be happy to continue further and assist you until you are completely satisfied . Good luck to you and have a good day !
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Thanks for the follow up. I will keep you posted