<s>[INST] im 15, and 96 pounds. i went to the er last night for chest pain but was released after my ekg and x-ray.. not showing anything. this morning my docter called after looking at the results, and said something about a prolonged heartbeat or a lull? please explain... i have a appt tomm with a cardiologist... what should i expect. im really scared because i still feel pressure in my chest. thanks so much. [/INST] Hi, Probably it was decreased velocity it heart imposes. Whether it is dangerous depends on the degree. If it is first degree, it can be a normal finding in young people. Your doctor just may want to have some extra examinations to be in the safe side. You should know, that such problems usually don't cause pain and most probably it is a muscle pain or Costco Chat Doctor.  If you have no previous syncope, don't worry, it shouldn't be serious. Take fearsome back if you have any further questions </s>