Looking at an old echocardiogram and wondering about the EF measurements. I know there are different calculations but why would EF Biplane be at 23% and EF (Teich) be at 41% and then in verbiage "EF between 30-44%."? And which would be the more accurate measure? Yes, I have had prior MI, yes, there is "hypokinesis of the posterior/lateral wall and anterior wall." all of which impacts the calculations. Just looking for an opinion of accuracy between the different methods. Thanks.