Over the last 6 weeks or so I have had occasional episodes of a fast heart rate-occasionally waking me at night, or sometimes during the day. Mostly they have just passed quickly and I didn't think too much about it. Over the weekend I had it most of the day Friday, and by Friday dinner heart rate was pretty high (130s) it stayed that way all evening and I lay in bed listening to it thud away until I couldn't take it anymore and went to the ER. They ended up admitting me, giving me tons of fluids-chest xray, blood and urine test, echocardiogram etc. Heart appears completely normal, blood tests normal. It has gone down for the most part, although has not completely gone away- feeling it at least a couple of times a day and rate is frequently in the 100 range which is high for me. I did have some markers for a uti- but no symptoms. In the hospital they didn't think this could be the cause although my dr seems to think it might and started me on antibiotics. I was suspicious of thyroid, but all those tests seem normal. I am also wondering about hormones- none of the drs seem to think that could be it-too intense and sudden. I have an appointment scheduled with my midwife who hopefully can test those levels and might have some insight, but in the meantime any other oddball things this could be? Anyone ever have this? Nobody seems to think it is particularly dangerous but it sure is annoying.