Tachycardia and ejection fraction

Hello,
I am a usually healthy twenty-three year old female (5'5" about 115 lbs). About a year and a half ago I went to see my dr. due to a cold and he said he heard a heart murmur. My Dr. said he thought this was benign, but had me do an echocardiogram to make sure. During the test my heart rate was quite high maxing out at 150 and staying for the most part around 110-120. I was EXTREMELY nervous about the test and knew my heart was beating fast during it. The echo showed no abnormalities and my ejection fraction was 55. The cardiologist who read the results found nothing structurally wrong, but asked my PCP about the high pulse. My PCP talked with me and felt it was due to my being nervous during the test, as my pulse is normally in the 80's. My question, though, is whether 55 is really representative of my true ejection fraction? Isn't it usually higher during exercise (or when one's pulse is high as mine was)? And if so, would my resting ejection fraction be much lower and therefore cause concern as it would be outside of the normal limits (as 55 is at the lower end of normal)? Also, is there anyway to raise it? I've been told an ef of 65 is not really better than 55 but I'm unsure if this is true. Thank you for any advice!

[Jerry_NJ]

I can believe you were a "nervous wreck", doctors and hospitals affect some people that way... and thus a high HR.  A resting HR of 80 is on the high end of normal, so a little nervous speed-up could get you into 150 range.

As for the EF, I'd think it would be lower at a high HR not higher.  This is a guess, but I believe the EF is the % of the blood in the ventricle that is ejected with each pump.  I'd think a quick pump at the higher HR levels would move less blood (%) per pump than a leisurely resting HR pump.

I could be wrong on this, so if you get another answer that disagrees, I restate I am guessing.  Your doctor didn't see any problem, try not to worry.