Just got back from seeing my doctor...because I ve been experiencing lots of light-headedness and every time I ve checked my heartrate during this past week, it s been between 120 and 150 during rest or just lightly moving around. The doctor said that he is referrring me to a cardiologist , because he heard an S-3 and a very soft S-1. ( Heart rate was around 130 and irregularly irregular ), B/P was 99/56. My ECG showed low cardiac output in some leads...and I had a couple of pauses that were around 3 seconds. He said that my WBC is high (16,000) and my ESR was just over 100. He told me that until I see the cardiologist, I should avoid doing anything that would raise my heartrate above resting . I could tell that he sounded concerned. Do you have any idea what could be going on?