question: Hello doctor,  Recently my thyroid went up and since then, I have been feeling a gushing and thumping feeling in my chest that only happens at night. The feeling is in my upper chest. It lasts for two hours off and on. The doctor put me on Metoprolol tartrate 25 mg. He told me to cut the pill in half. Then take one half of the pill after my meal in the morning and after dinner. But I still have this same feeling. So the doctor put a halter monitor on me and told me to take half the pill after breakfast and one whole pill after dinner to see if the thumping feeling slows down. The doctor also told me it was the left ventricle and interventricular artery not meeting which is why this is occurring. What else can I do I can not take this feeling it is very distracting, and I want to know if there is anything else that can help? I also have elevated lymph nodes in the armpit near my left breast. I have attached the documents and medication list.