I have been having episodes of chest pressure and shortness of breath on and off for several years, it has always been blamed on my thyroid (hypo), and have lots of periods of bradycardia (my heart rate is 54-60) but this week I was hospitalized overnight twice for chest pressure, dizziness, nausea, and sever shortness of breath. My vitals are ok, all except my heart rate that would go from 120 (resting) to normal than to 46 then to normal augh! My oxygen levels was 93% on room air, and I am very very tired. I have had 1 near fainting spell, and episodes of sever sweating followed by being very flushed. No one seems to know what is going on. My stress test from Sept was neg, my cat scan, MRI, chest x-ray, and ecg were negative, they did an echocardiogram which is also negative. They are making me think I am nuts!! One of the nurses I work with told the docs they should consider re-duing the stress, she said "I know her and this is not what she looks like" I really feel terrible all the time. No energy, and now when I eat I get nauseated, short of breath and chest pressure that does not want to go away. anyone have any ideas????