Hi, welcome to our site. I am Dr Saumya Mittal. Read your query. That is a very significant question and i appreciate your problem. I will try my best to answer your query there are many other causes for left arm pain besides the cardiac issues. I will not concentrate in the cardiac issues because that have already been dealt with by your doctor. The other causes include 1. cervical spondylosis- suggest a x ray, preferably an mri spine. the pain in the left arm is because the nerves coming out of the spinal cord mey be getting compressed. and this may be resulting into the pain that usualy radiated from the neck, and down to the arm 2. muscle strain- the muscles are all attached to the bones. so when you have left arm pain, it may be possible that there is an inherent muscle trauma that may be causing pain. alternatively, the attachments of the meuscles to the bone may be weak or traumatized and may therefore lead to pain as well. an ncv or emg may help diagnose this 3. gastritis. the nerve supple to the heart and the stomach is the same. and this also supplies the arm. so when you have severe gastritis, the nerve takes the signal to the brain. now since the brain recieves signals from all three portions, it misreads the signals as pain in those parts. and thus we feel pain in left arm. medically, this is known as referred pain.an endoscopy may help diagnose this 4. it may be due to some pleuritis. in fact the sharp shooting/stabbing pain in chest on inspiration is typical to pleuritis. pleura is the covering of lungs. now lungs per se do not feel any pain. but pleura does. so any infection or inflammation involving the pleura may cause pain. accordingly, the pleural pain may be due to chest (lung) involvement or due to the covering. an x ray chest or ct chest may help 5. rarely, an abdominal pathology, like tuberculosis of abdomen irritates the diaphragm. diaphragm is a muscle between the chest and abdomen that helps control the breathing. when this is inflamed, there may be more pain too- again by referred pain. an ultrasound or abdominal mri may help I hope this helps you. Inform the reports mentioned above so i can be of help further. Best of luck. I have given you the answer to the maximum considering the information provided. The results of the tests could further enhance my answer to you. Please do understand that some details could be extracted from a detailed history and examination. Looking forward to your return query with the details asked so that I can help you further. (If the answer has helped you, please indicate this)