Should I be worried about heart rate/blood pressure?

I've been passingout, or coming close to passing out, quite often in the mornings for about a month.  Occasionally it happens in the afternoons also, but generally the first hour of the morning is the worst.  

I've been to the doctor, and all my blood work has come out perfect.  My heart rate on the Holter monitor was as low as 42 at one point, and spiked at 157 while walking up one flight of stairs at home.  

I ended up having an echocardiogram and a stress test.  During the ultrasound portion, I noticed that my resting heart rate while lying there was hovering between 48 and 52.  I'm not an "athelete" by any stretch, is this far too low for me?  

Also, historically, my blood pressure has been a pristine 115/60, no matter how much I weight, what my stress level is, etc.  However on stress test day, my sitting blood pressure was 90/60, and my standing blood pressure was 85/72.  This numbers are completely foreign to me!  Should I be worried?  

They ultimatley determined my heart valves are fine, but what now?  

[Michael J. McWilliams, M.D.]

Some people just having low resting heart rates even if they aren't athletes.  If you aren't having symptoms with low heart rates, I would not worry about the low heart rates.

it is hard to say why your blood pressures are lower than they used to be.  I have seen people in clinic with similar symptoms -- mostly young women in the late 20 or 30's.  There is not good explanation that I know of at least to say why this happened.

I don't have a good answer for you on this one but I am not sure that you will find a definite answer.  I would make sure your thyroid and possibly your cortisol are ok.

Depending on if there are other symptoms or the results of a holter, I would think about whether this could be inappropriate sinus tachcyardia.

[Pjohnson7211]

Oh, I suppose I should add, I'm 36 years old.  Age might help there.  

[Pjohnson7211]

Okay, thanks.  

Fainting, and the subsequent Holter results, are how I even know of these issues in the first place.  

I may have the thyroid checked a bit more.  My mother has hypothyroidism.  My blood tests for the thyroid level came back normal, but talking to Mom last night, so did hers. It was a later test that finally caught the issue.  

Thanks for your help.  

[antiphonal]

A related discussion, Should I look deeper? was started.