Ever since I had my thymectomy I have experienced chest pain on the right side. Sometimes doing just light lifting will cause them. My neuro said it's from nerve damage that causes pain in the chest muscles. I remembered reading that could happen when I signed the consent forms. However earlier this month my husband and I went to California to visit our son and he took us to the San Diego Zoo and after a short time of slow walking, I got them on the left side for the first time. It only lasted about 15 minutes, but it scared me. I've since had it happen several more times. I saw my GP the day after we got back and he sent me to a cardiologist which I saw this morning. I forget the name of the test he did, but he first did an echocardiogram then a stress test on the treadmill, and while my heart was still pounding, he did another echocardiogram. He said my heart is fine!!! What a relief. He said the nerves on the right may have somehow connected to the left side, but he's not sure. I see my GP again the first week of July, so I'll see what he has to say. I'm not too concerned about it now. I had to laugh when he said I lasted longer on the treadmill than he thought I would. A few years ago with the MG, I wouldn't have even gotten started!