bronchitis??

hello. I have had a cough pretty much all winter.I rarely get sick and i thought i would just get over it so i prolonged going to the dr. When i started coughing up mucus and losing my voice i decided to go. My dr said that it was most likely bronchitis. He took chest x-ray and also an ekg because he was concerned with the fact that my pulse was high. He put me on antibiotic. Zithromax I think. After a week there wasn't much change. I went back and he put me on another antibiotic(can't remember the name but was a blue capsule) and also advair powder inhaler. he was still concerned about the high pulse and got me to go to the er where they did a catscan and various blood tests and everything was normal accept they said my bronchial tubes looked real inflammed. And they said when you have an infection that long it can cause your pulse to go up. So along with what my dr had already prescribed, the er dr prescribed me cough syrup and a cortizone steroid pack. After I was taking all that I was really noticing a difference and my pulse was back down to normal. I went back to the dr a week later and was feeling good, but since they suspected I had neumonia he suggested staying on the same antibiotic for one more week and return back in 2 weeks. Soon after I finished the antibiotic i noticed the mucus and cough coming back slowly. When I went back to the dr he noticed my high pulse was coming back too. So, he was concerned and wants me to see a cardiologist eventually. It seemed logical that my high pulse was connected with the infection/bronchitis since it improved when I was feeling better. So, the dr prescribed me the cortizone steroid again, and an asthma medication because I do have some mild asthma and what he said was another antibiotic (my 4th round), which I didn't realize till later, I think that it was the same antibiotic he first prescribed me (zithromax). So I don't know if it's really going to help me since it didn't before. I've been on it for 3 days and pulse still above normal. Around 95-110. I wasn't able to contact my dr about getting a different antibiotic. I don't know what to do. I don't think that there is anything wrong with my heart because of all the tests I've had done, but i think this infection is causing my pulse rate to go up, but nothing seems to fully get rid of this infection.