Definitely start a journal. You can do it here if you want - just let me know if you need help.
And yes,
ejection fraction is an estimation and calculation. The best a tech can do is take two snapshots during an
echo - once when the ventricles are open, full and at rest, and once when they are at the peak of contraction. Then they have computer programs to map out the cross-sectional area of the ventricle when at rest and contracted, which after a bit of number crunching, they have their
ejection fraction. But part of the problem is, it's only in two dimensions. And the accuracy of the computer (or the tech) isn't perfect.
And I think that's why doctors don't get all that excited over ejection fractions that are just outside of established "normal" parameters, because there can be measuring flaws for a couple different reasons.
Let us know how things keep going.