I am from the Lupus board, and a nursing student. I just popped in here to be nosy. Anyhow, I also work on a cardiac unit and read the telemetry monitors. Being that you sound fairly active, and your stress echo was good I would not worry. That test measures if there are any blockages. If they said all is well, it must be. It is normal for someone who is active and gets cardio exercise to have low heartrates. I have taken care of patients who run a few miles a day, and thier heart rates run in the low 30's. So in this case low HR is good, it means your heart is strong. It is a muscle, and since you exercise it frequently it does not have to work as hard to do normal activity. As for the shortness of breath, as long as it is only when you are really exerting your self it sounds fine.
However, I would follow up with the sleep apnea. Did you have a sleep study? If you dont want to wear a breathing machine, or depending how mild your apnea is; you can get fitted for a mouth piece to stop the apnea. Losing weight can often make the apnea go away. I am not sure if 30 lbs is that big of a difference. I guess it depends on where you carry your lbs. (like is it only in your torso to affect your breathing). Good luck!
Dx: UCTD,Raynaud's,iron deficientcy anemia,proteinuria
Rx: Multi-rec folic 500, Celebrex 200 mg, Plaquenil 400mg, Ultram PRN