Can your heart beat get weaker as time goes? Maybe cancer or heart problems? I been to heart / lung / ent / hemat doc bunch tests all good except + meth challenge airway disease. Feel lump my throat and cnt feel heart beat in chest at rest or pace.

Detailed history. It sounds like you have a complex situation and have already had extensive testing. These little text boxes are not big enough to go through all the details, which is what a doctor would need to be able to help. You might consider a second opinion inbox consult here on HealthTap where you can share the records of your tests and have them reviewed.