I have an air bubble in my chest that fluctuates between my heart and the bottom of my throat. What could it be and how do I get rid of it?

If no injury. and no trouble swallowing, breathing, or with acid reflux, this could just be gas. Try Simethicone or antacid with Simethicone and see if it helps you belch. If that relieves it, nothing else is necessary. If not, you might have something else going on and should be seen, perhaps have an x-ray or esophageal study. Good luck!